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Drinking well water and occupational exposure to Herbicides is associated with chronic kidney disease, in Padavi-Sripura, Sri Lanka

Drinking well water and occupational exposure to Herbicides is associated with chronic kidney... Background: The chronic kidney disease of unknown etiology (CKDu) among paddy farmers in was first reported in 1994 and has now become most important public health issue in dry zone of Sri Lanka. The objective was to identify risk factors associated with the epidemic in an area with high prevalence. Methods: A case control study was carried out in Padavi-Sripura hospital in Trincomalee district. CKDu patients were defined using health ministry criteria. All confirmed cases (N = 125) fulfilling the entry criteria were recruited to the study. Control selection (N = 180) was done from people visiting the hospital for CKDu screening. Socio-demographic and data related to usage of applying pesticides and fertilizers were studied. Drinking water was also analyzed using ICP-MS and ELISA to determine the levels of metals and glyphosate. Results: Majority of patients were farmers (N = 107, 85.6%) and were educated up to ‘Ordinary Level’ (N = 92, 73.6%). We specifically analyzed for the effect modification of, farming by sex, which showed a significantly higher risk for male farmerswithOR4.69(95%CI1.06-20.69)incomparisontotheir female counterparts.Inthe multivariableanalysisthe highest risk for CKDu was observed among participants who drank well water (OR 2.52, 95% CI 1.12-5.70) and had history of drinking water from an abandoned well (OR 5.43, 95% CI 2.88-10.26) and spray glyphosate (OR 5.12, 95% CI 2.33-11.26) as a pesticide. Water analysis showed significantly higher amount of hardness, electrical conductivity and glyphosate levels in abandoned wells. In addition Ca, Mg, Ba, Sr, Fe, Ti, V and Sr were high in abandoned wells. Surface water from reservoirs in the endemic area also showed contamination with glyphosate but at a much lower level. Glyphosate was notseeninwater samplesinthe Colombo district. Conclusion: The current study strongly favors the hypothesis that CKDu epidemic among farmers in dry zone of Sri Lanka is associated with, history of drinking water from a well that was abandoned. In addition, it is associated with spraying glyphosate and other pesticides in paddy fields. Farmers do not use personnel protective equipments and wears scanty clothing due to heat when spraying pesticides. Keywords: Chronic Kidney disease, Tubulointerstitial nephritis, Well water, Herbicides, Glyphosate, Sri Lanka Background denote this condition where “u” stands for unknown or A chronic kidney disease (CKD) with unusual character- uncertain etiology. Twenty years after the first report, istics was first reported in 1994 among middle-aged this disease is the most important public health issue in paddy farmers in Padaviya farming colony in the north- NCP with more than 50,000 estimated patients, and eastern boarder of the North Central Province (NCP) of spreading on an epidemic scale to other farming areas in Sri Lanka [1]. Some authors used the term CKDu to the Northern, Eastern, North Western, Central, and Uva provinces of the country [2]. The prevalence of the dis- ease among those aged 15–70 years is estimated at * Correspondence: jayasumanalk@yahoo.com 15.1% in the Anuradhapura district in NCP [3]. The Department of Pharmacology, Faculty of Medicine, Rajarata University of Sri Lanka, Anuradhapura 50008, Sri Lanka unique feature of this CKD epidemic is that its etiology Full list of author information is available at the end of the article © 2015 Jayasumana et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Jayasumana et al. Environmental Health 2015, 14:6 Page 2 of 10 http://www.ehjournal.net/content/14/1/6 does not link to commonly known risk factors for CKD Selection of controls such as diabetes mellitus, hypertension, and glomerulo- Controls were selected from the same Padavi-Sripura nephritis [3]. area as the cases, and shared the same environment as The CKD patients in this epidemic are asymptomatic the cases. Screening for controls consists of testing for until the later stages of the disease and show tubular serum creatinine and urine microalbumin.180 healthy interstitial nephritis associated with mononuclear cell in- individuals who came to the hospital for screening for filtration with development of glomerular sclerosis and CKDu during the study period were selected as controls tubular atrophy [4]. The characteristic geographical dis- after excluding CKDu and other chronic diseases. Controls tribution of the disease and associated socioeconomic were not matched for age. factors are suggestive of environmental and occupational Medical officers and university academics that were origins. Tubulo-interstitial damage and negative immune- trained collected demographic and risk factor data using fluorescence for IgG, IgM, and complement-3 are more in a pre-designed questionnaire. Age, sex, marital status, favor of a toxic nephropathy [5]. Several research studies education, current and past sources of drinking water, conducted to determine the cause of CKDu, have specu- history of smoking, illicit alcohol usage, chewing betel lated about the causative role of agrochemicals. Toxins and tobacco, chronic use of painkillers-particularly Non- postulated so far as etiological factors include arsenic (As), Steroidal Anti Inflammatory Drugs (NSAIDs), and family cadmium (Cd), nephrotoxic pesticides and fluoride [1,2,6]. history of death due to CKD were collected. The partici- However, none of the studies performed so far has focused pants’ place of residence and the predominant occupa- on the link between the disease and the exact type of tion during the last ten years were recorded. The pesticides used. The objective of this study was to identify information on whether the participants are presently the major risk factors associated with the CKDu in the drinking from well, tap, spring or water from reservoirs Padavi-Sripura area in Sri Lanka. was collected. They were also asked about source of drinking water used previously (during the last ten years) Methods and specifically probed about history of drinking water Study setting from a well that is currently abandoned. This was be- Sripura is a divisional secretariat of Trincomalee district of cause water from some wells has become distasteful over the Eastern province bordering to NCP with a population time and people have stopped drinking from these wells of 11,858. This area has been identified as having one of (abandoned wells). These wells were defined as aban- the highest prevalence of CKDu. Authors carried out a doned wells for the purpose of this study. case control study to determine the association between A detailed history of applying fertilizer (which is usu- CKDu and selected socio-demographic factors, and a ally performed manually with bare hands) and pesticides number of variables related to the use of agrochemicals. (done with hand held sprayers) was obtained. The type of pesticide most widely used during the respondent’s Selection of cases entire lifetime was also recorded. The use of organo- All patients (125) with CKDu were recruited from the phospates, paraquat, 2-methyl-4-chlorophenoxyacetic patients who attended a medical clinic at Padavi-Sripura acid (MCPA), glyphosate, bispyribac, carbofuran, man- divisional hospital in Sri Lanka. Cases were defined as cozeb and other commonly used pesticides were cat- subjects diagnosed with CKD and defined as CKDu ac- egorically identified. As many farmers did not recognize cording to the criteria defined by the Sri Lanka Ministry the type of pesticide by their chemical name a list of com- of Health [7]. monly available trade names were used to collect the data. These multiple brands were later lumped together based 1. No past history of, or current treatment for, diabetes upon their chemical name. Ethical clearance for the study mellitus or chronic and/or severe hypertension, was obtained from the ethics review committee of the Fac- history of snakebite, urological disease of known ulty of Medicine, Rajarata University of Sri Lanka. Written etiology or glomerulonephritis. informed consent was obtained from all participants. 2. Normal Glycosylated Hemoglobin level (HbA1C˂6.5%). Water analysis 3. Blood Pressure ˂160/100 mmHg untreated or ˂140/ Water samples were collected at 34 wells in Padavi- 90 mmHg on up to two antihypertensive agents. Sripura and two reservoirs (Padaviya wewa and Jayanthi wewa). Padaviya wewa (2357 ha) was built in 5th century The patients with CKDu were referred to the consult- A.C and was renovated in 11 century A.C and in 1956. ant nephrologist and the diagnosis was confirmed. All Jayanthi wewa belongs to the cascade system of Padaviya confirmed cases of CKDu was recruited. Data collection wewa [8]. Water samples were also collected from two started in April 2012 and ended in October 2012. wells and three different locations of mainline pipe born Jayasumana et al. Environmental Health 2015, 14:6 Page 3 of 10 http://www.ehjournal.net/content/14/1/6 water from Colombo district, a non-endemic area for The analytical detection limit was calculated as the CKDu. Also a sample of water from a domestic reverse concentration of the element which gave a detectable osmosis (RO) machine in Padavi-Sripura was collected. signal above the background noise at greater than the 18 of the wells tested at Padavi-Sripura were abandoned 99% confidence level, and the detection limit was calcu- or not used for drinking. 200 mL polyethylene bottles lated as the mean of blanks plus 3 times the standard were decontaminated by repeated soaking in 2 M nitric deviation of the mean. acid (24 h) and were used for water collection. Following the collection of samples, bottle were bagged and then Detection of glyphosate stored in a cooler box. All bottles were refrigerated We decided to measure glyphosate because two current (under 4°C) and subsequently transported in a cooler authors have formulated and published a detailed hy- box to the Institute for Integrated Research in Materials, pothesis that incriminates glyphosate that chelates with Environments and Society (IIRMES) lab, California State heavy metals as a causative factor for CKDu and also con- University, Long Beach (CSULB), USA where they were tributing to water hardness [9]. Enzyme-immunoassay in analyzed. We measured mono and polyvalent cations in the analysis of glyphosate in water is a cost effective and the water to test a hypothesis about heavy metals and reliable method. ELISA method has a lower detection elements contributing to water hardness as a possible limit of glyphosate (0.6 μg/L) compared to HPLC method cause in CKDu [9]. (50 μg/L) although there was no statistically significant difference between two methods [10]. ICP MS analysis Water samples were tested for glyphosate by Enzyme- Major and trace elements were measured using an In- immunoassay using commercial test kits (US Biocontract ductively Coupled Plasma Mass Spectrometer (ICP-MS; Inc., San Diego, CA) according to the manufactures proto- HP 4500, Agilent Technologies, Palo Alto, CA) equipped col. This test is based on the competition between the with a quadrupole analyzer and octopole collision/reac- glyphosate and glyphosate-horseradish peroxidase con- tion cell that can be pressurized with either a hydrogen jugate for binding to the rabbit antibody raised against (H ) or helium (He) reaction gas. Sample was injected glyphosate. Validation of the ELISA test was done in com- at the rate of 0.4 mL/min using a peristaltic pump. parison with GC-MS. To study the recovery rate several Carrier Argon (Ar) gas at rate of 1.2 L/min through samples were spiked with 10 μg/L of glyphosate and it was a Babbington-style nebulizer was introduced into a measured in the supernatant by using ELISA. Peltier-cooled double-pass spray-chamber at 2°C. The 1.0 L/min auxiliary Ar and 12.0 L/min plasma gas Ar Data analysis were added for a total of 14.2 L/min separated from Associations were investigated with frequency tables. nickel cones. The ICP-MS was tuned under standard Continuous variables were summarized by means and settings by running the manufacturer's recommended standard deviations. Categorical variables were dichoto- tuning solution containing 10 μg/L of Li, Y, Ce, Tl, mized for analyses. Odds ratios (OR), 95% confidence inter- and Co (Agilent internal standard mix) for resolution vals, and p-values were obtained to assess the association and sensitivity. Interference levels were reduced by between exposure and developing CKDu. Data were ana- optimizing plasma conditions to produce low oxide lyzed using SPSS (version 22). and doubly charged ions (formation ratio of <1.0%) and residual matrix interferences were removed using the collision/reaction processes in the Octopole Reaction Results System. Of the 125 diagnosed CKDu patients, significantly higher number (n = 89, 71.2%) was male. The mean age of male Accuracy, precision and detection limits (45.51 ± 19.78 years) and female (47.45 ± 17.51 years) pa- Accuracy was measured using the spiked standard solu- tients did not show any significant difference. Majority tions (Agilent Technologies). Ultrapure water (MilliQ) of the CKDu patients included in the study had educa- was used as blank (1 blank per each 10 sample batch). tion up to ordinary level (n = 92, 73.6%) and were Precision (reproducibility) was ascertained using farmers (n = 107, 85.6%). Only nine (7.2%) CKDu pa- within-day replicate analysis of samples. The Relative tients reported death of a close family member due to Standard Deviation (%RSD = SD/χ of the replicate CKD. Of the CKDu patients, 86 (96.6%) males were values X 100%; χ is mean value) was calculated to give farmers compared to 21 (58.3%) females. Controls in- an indication of sample preparation and analytical pre- cluded 180 healthy individual presented to the study site cision. Replicates of each day provided an indication for screening for CKDu. This included 98 (54.4%) males of within-day precision. and 82 (45.6%) females. Jayasumana et al. Environmental Health 2015, 14:6 Page 4 of 10 http://www.ehjournal.net/content/14/1/6 Factors associated with CKDu High conductance indicates high concentration of In the univariable analysis (Table 1), male sex (OR 2.07, dissolved-solids. This can affect the palatability of 95% CI 1.27-3.36), engaging in farming related activities water. Conductivity was highest among the abandoned (OR 3.12, 95% CI 1.74-5.61), pesticide application (OR wells. Content of iron in abandoned wells was also sig- 3.31, 95% CI 2.04-5.36), applying fertilizers (OR 2.37, nificantly high. 95% CI 1.43-3.93), drinking well water (OR 4.82, 95% CI Glyphosate (Gly) concentration also showed a marked 2.27-10.24) and a history of drinking from recently aban- difference between serving and abandoned wells doned well (OR 6.93, 95% CI3.87-12.40) was significantly (Table 3). All the abandoned wells except for one associated with CKDu. We specifically analyzed for the (94%) contained more than 1 μg/L of glyphosate where effect modification of, farming by sex, which showed a as among the serving wells only 31% contained gly- significantly higher risk for male farmers with OR 4.69 phosate above the 1 μg/L level. There was trace (95% CI 1.06-20.69) in comparison to their female coun- amounts of glyphosate in the surface water in two res- terparts. CKDu was associated with life time exposure to ervoirs indicate the glyphosate may have been washed different kinds of pesticides considered in this study ex- off from the agricultural or paddy lands. However gly- cept carbofuran. Glyphosate, a total weed killer, was the phosate was not seen in well or mainline pipe borne most widely used pesticide among farmers in both water in Colombo district. groups. In general, subjects who sprayed glyphosate were four times more likely to have CKDu compared to those Discussion without such a history. The present study revealed that male farmers from In the multivariable analysis, we investigated the un- Padavi-Sripura, who spray glyphosate, drink well water confounded effect of individual exposure factors after and had history of drinking from an abandoned well, are adjustment for age, sex, educational level, having a death at a significantly higher risk of developing CKDu. This among family members due to CKD and other exposure association is evident even after adjusting for all the factors related to agrochemical use. Drinking well water baseline and exposure variables. This is the first study in (OR 2.52, 95% CI 1.12-5.70), history of drinking from re- Sri Lanka that analyses the association of CKDu among cently abandoned well (OR 5.43, 95% CI 2.88-10.26) and farmers with the type of pesticide and most widely used use of glyphosate 5.12 (2.33-11.26) were the factors sig- pesticide during their lifetime. nificantly associated with CKDu. A significant difference The only pesticide not associated with CKDu in uni- between groups has been detected with related to pesti- variable analysis is carbofuran an insecticide in granular cide application (OR 2.34: 95% CI 0.97- 5.57) however, form. All other pesticides considered in this study are in perhaps with a smaller sample size, this difference would liquid form and easily absorbable through skin and by have proved to be not statistically significant. inhalation, particularly during manual spray. Paraquat was a common herbicide used by the paddy farmers since 1960s [12]. However, it was phased out gradually Analysis of drinking water samples due to 400 to 500 deaths per year in Sri Lanka due to its There was a significant difference between abandoned use for committing suicide [13]. Paraquat also can cause (not used for drinking now) and serving wells (presently respiratory, skin and mucosal irritation among those used for drinking) in total permanent hardness (calcu- who spray it [14]. In 2010 pesticide technical advisory lated value using calcium and magnesium). Barium, iron committee of Sri Lanka decided to ban the use of para- and strontium were significantly high in abandoned quat for paddy cultivation [15]. wells (Table 2). The ban on paraquat prompted most farmers to According to the classification by United States switch to using glyphosate as an alternative herbicide. Geological Survey on water hardness [11], all the other There are no immediate symptoms among sprayers of abandoned wells were classified as having very high glyphosate. However, there are important differences be- hardness except for two. However, none of the cur- tween these two pesticides. Paraquat is a contact herbi- rently serving wells can be classified as such and be- cide but glyphosate is a trans-locating herbicide with longs to either moderately hard or hard category of anti-microbial action that softens the earth, paving the water hardness. Surface water from Padaviya reservoir way for ‘till-less’ farming [16]. Glyphosate came to the had very low hardness (i.e. soft) that was similar to the market in 1971 but there are no details of when it was well water and mainline pipe borne water in the first available in Sri Lanka. However, it has become most Colombo district. In parallel, calcium, magnesium, bar- widely used pesticide in Sri Lanka [9]. The amount of ium and strontium levels for water in non-endemic glyphosate imported was 5.3 million kg and this repre- Colombo district was also low in comparison to the sents more than half (52%) of the total pesticides (in- endemic area. cluding all other herbicides, insecticides, and fungicides) Jayasumana et al. Environmental Health 2015, 14:6 Page 5 of 10 http://www.ehjournal.net/content/14/1/6 Table 1 The distribution the demographic variables and other risk factors, by CKDu outcome CKDu Patients (Cases) N = 125(%) Non CKD (Controls) N = 180 (%) Unadjusted OR (95% CI) p-value Gender Male 89 (71.2) 98 (54.4) 2.07 (1.27-3.36) 0.0031* Female 36 (18.8) 82 (45.6) Education Up to OL 92 (73.6) 147 (81.7) 0.64 (0.37-1.10) 0.1041 Higher education 33 (26.4) 33 (18.3) Farming Yes 107 (85.6) 118 (65.6) 3.12 (1.74-5.61) < 0.0001* No 18 (14.4) 62 (34.4) Pesticide application Yes 86 (68.8) 72 (40.0) 3.31 (2.04-5.36) <0.0001* No 39 (31.2) 108 (60.0) Applying Fertilizer Yes 95 (76.0) 103 (57.2) 2.37 (1.43-3.93) < 0.0001* No 30 (24.0) 77 (42.8) Drinking well water Yes 116 (92.8) 131 (72.8) 4.82 (2.27-10.24) < 0.0001* No 9 (7.2) 49 (27.2) History of drinking water from abandoned well Yes 58 (46.4) 20 (11.1) 6.93 (3.87-12.40) < 0.0001* No 67 (53.6) 160 (88.9) Smoking Yes 36 (28.8) 37 (20.6) 1.56 (0.92-2.66) 0.0970 No 89 (71.2) 143 (79.4) Illicit alcohol Yes 17 (13.6) 21 (11.7) 1.19 (0.60-2.36) 0.6150 No 108 (86.4) 159 (88.3) Betel chewing Yes 106 (84.8) 152 (84.4) 1.03 (0.55-1.94)0.9326 No 19 (15.2) 28 (15.6) Tobacco with betel chewing Yes 92 (73.6) 129 (71.7) 1.10 (0.66-1.84) 0.7101 No 33 (26.4) 51 (28.3) Long term pain killer use Yes 10 (8.0) 15 (8.3) 0.96 (0.42-2.20) 0.9169 No 115 (92.0) 165 (91.7) Family history of death due to CKD Yes 9 (7.2) 13 (7.2) 1.00 (0.41- 2.41) 0.9941 No 116 (92.8) 167 (92.8) Ever used Organophosphate Yes 54 (43.2) 54 (30.0) 1.77 (1.10-2.86) 0.0183* No 71 (56.8) 126 (70.0) Ever used Paraquat Yes 64 (51.2) 53 (29.4) 2.51 (1.56-4.04) 0.0001* Jayasumana et al. Environmental Health 2015, 14:6 Page 6 of 10 http://www.ehjournal.net/content/14/1/6 Table 1 The distribution the demographic variables and other risk factors, by CKDu outcome (Continued) No 61 (48.8) 127 (70.6) Ever used MCPA Yes 56 (44.8) 56 (31.1) 1.80 (1.12-2.88) 0.0152* No 69 (55.2) 124 (68.9) Ever used Glyphosate Yes 82 (65.6) 55 (30.6) 4.33 (2.66-7.05) <0.0001* No 43 (34.4) 125 (69.4) Ever used Bispyribac Yes 64 (51.2) 62 (34.4) 2.00 (1.25-3.18) 0.0037* No 61 (48.8) 118 (65.6) Ever used Carbofuran Yes 46 (36.8) 51 (28.3) 1.47 (0.91-2.40) 0.1192 No 79 (63.2) 129 (71.7) Ever used Mancozeb Yes 46 (36.8) 51 (28.3) 1.94(1.21-3.13) 0.0062* No 79 (63.2) 129 (71.7) *P < 0.05. imported in 2012 [9]. There are no studies that report increases the risk of getting CKDu with people who nephrotoxic properties of glyphosate on humans. used glyphosate having the highest risk. However, several animal studies provide evidence for Certain pesticides are known to be associated with nephrotoxic properties of glyphosate [17-22]. Toxicity CKDu in humans. A study done in India demonstrated of glyphosate to common hourglass tree frog in Sri that there was a significant correlation between plasma Lanka is previously reported [23]. levels of organochlorine and decrease in GFR and the de- Byspiribac which is another weed killer also in- velopment of CKD [24]. Internationally, the use of organo- creases the risk of CKDu. Organophosphate com- chlorine and arsenical pesticides at cotton fields in the pounds and moncozeb, are the leading insecticide and Aral Sea area which caused an epidemic of tubular kidney fungicide respectively, used by the farmers in the damage and abnormal increase of non-communicable dis- Padavi-Sripura area. The use of all these pesticides eases in central-Asia, is considered to be one of the world’s Table 2 Hardness and related parameters in drinking water samples mg/L μg/L mg/L μs/cm Well type Na K Ca Mg Ba Sr Hardness Condutivity Abandoned wells in Sripura (n = 18) Mean 74.8 0.9 51.8 28.0 150.7 572.4 243.6 877.2 Median 57.1 0.8 53.2 29.6 142.3 519.0 234.5 623.0 Serving wells in Sripura (n = 16) Mean 51.9 0.6 29.0 13.0 89.4 269.1 125.9 465.0 Median 38.6 0.7 28.5 11.6 83.9 265.0 121.0 509.5 U 77.5 97.0 26.5 24.5 64.0 31.0 6.0 44.0 Z −2.295 −1.629 −4.054 −4.124 −2.760 −3.899 −4.762 −3.450 P Value .0217* .1034 .0001** .0000** 0.0058** .0001** .0000** .0006** Surface water 5.85 0.45 10.6 1.15 10.4 46 31.2 79.5 RO water 3.1 0.2 0.6 0.6 2.1 4.6 4.0 22.0 Colombo well 2.6 0.7 6.8 0.8 16.4 13.1 20.2 49 Colombo main 2.5 0.7 6.8 0.8 16.5 14.5 20.0 49 *P < 0.05, **P < 0.01, # two sample Wilcoxan rank-sum (Mann–Whitney) test. Jayasumana et al. Environmental Health 2015, 14:6 Page 7 of 10 http://www.ehjournal.net/content/14/1/6 Table 3 Trace metal and glyphosate content in drinking water samples Abandoned wells Serving wells U Z P value Surface Ro Colombo Colombo water water well tap Mean Median Mean Median Al 2.2 1.0 2.9 2.2 117.5 −0.916 0.3596 3.5 <0.1 6.7 71.6 Sb 3.2 0.9 4.5 2.9 127.0 −0.587 0.5570 3.4 0.1 0.3 0.5 As 0.8 0.4 0.3 0.3 104.5 −1.381 0.1674 0.2 0.2 <0.5 <0.1 Cd 0.04 0.0 0.04 0.0 138.0 −0.247 0.8051 0.1 0.1 0.1 0.1 Cr 1.0 0.6 0.5 0.0 103.0 −1.495 0.1348 0.3 0.4 <0.1 <0.1 Co 0.07 0.1 0.2 0.1 118.0 −0.968 0.3329 0.1 <0.1 0.1 0.2 Cu 1.4 1.2 1.9 1.0 107.5 −1.264 0.2063 0.4 3.5 0.3 0.4 Fe 90.5 76.6 45.2 40 60.0 −2.898 0.0038** 20.0 1.5 17.4 26.1 Pb 0.5 0.1 0.2 0.1 124.0 −0.791 0.4287 0.1 0.2 0.1 0.1 Mn 2.8 1.1 2.0 0.3 98.5 −1.573 0.1156 0.8 0.4 5.5 6.4 Mo 1.5 1.4 1.1 0.8 97.5 −1.609 0.1077 0.3 1.0 0.3 0.4 Ni 0.8 0.7 3.1 0.6 140.0 −0.139 0.8897 0.3 0.8 0.1 0.2 Se 0.7 0.7 0.3 0.2 65.5 −2.731 0.0063** 0.4 0.3 <0.1 <0.1 Ag 0.01 0.0 0.02 0.0 133.5 −0.736 0.4615 <0.1 0.1 <0.1 0.1 Tl 0.1 0.1 0.05 0.0 129.0 −0.582 0.5603 0.1 0.1 <0.1 <0.1 Sn 0.3 0.3 0.3 0.3 143.0 −0.038 0.9696 0.3 0.2 0.3 0.3 Ti 0.8 0.8 0.6 0.7 85.5 −2.047 0.0406* 0.2 0.3 0.3 0.3 V 14.4 10.5 17.4 6.3 84.5 −2.053 0.0400* 1.4 0.8 0.3 0.3 Zn 4.3 2.3 7.7 3.4 115.0 −1.001 0.3168 6.8 6.1 0.8 0.7 Gly 3.5 3.2 0.7 0.6 15.0 −4.456 0.0000** 0.05 ND ND ND *P < 0.05, **P < 0.01, # two sample Wilcoxan rank-sum (Mann–Whitney) test, Glyphosate. greatest ecological disasters [25-27]. Moreover, a CKDu and zinc also contribute to the hardness in water but epidemic very similar to that of Sri Lanka has been identi- not shown here in the calculation of traditional hardness fied in agricultural communities in Andra and Odisha, [33]. These metals contribute to the increased dissolved two southeastern provinces of India [28,29], upper Egypt solids and enhanced conductivity of the water. Unpalat- [30] and predominantly among young male farm workers ability and the inability to use it for cooking purposes in the pacific coastal region of Central American countries may have driven people to abandon these wells. These of El Salvador, Nicaragua, and Costa Rica [31,32]. Similar conditions have made it necessary for the residents in to Sri Lankan and Indian scenarios the etiology of CKDu the endemic area to travel longer distances to obtain in Mesoamerica is not linked to the most frequently water from the currently serving wells, which are be- known causes such as diabetes mellitus and hypertension. coming lesser in numbers as more and more wells get Drinking water previously from an abandoned well in- abandoned due to increasing hardness. Most of the resi- creases the risk of developing CKDu almost seven times dents indicate that the hardness and the objectionable in univariable analysis. Drinking well water and having a taste are on the increase even in the currently serving history of drinking water from a well abandoned within wells in comparison to the surface water. The poor taste the last 10 years are significant predictors of CKDu. The and the scarcity of the water itself may cause people in abandoning of certain shallow wells in which water has the Padavi-Sripura to drink less water thus contributing previously been used for drinking purposes is a common to further dehydration and deteriorating renal function. phenomenon in the CKDu endemic area. Long-term Organic compounds in the water also can contribute to- residents in this area complain that the ground water wards the taste of water. The unknown factor here is hardness has been steadily increasing over the last two glyphosate. Do the pesticides contribute to the water decades rendering the water increasingly unpalatable taste? Another aspect of these herbicides (glyphosate, and not suitable for cooking. bispyribac, MCPA, and paraquat) is that they process Hardness of water from abandoned wells is associated one or more carboxyl groups that are capable of retain- with the presence of metals such as calcium and magne- ing metals [34-36]. Calcium, Magnesium and Strontium sium. Aluminum, barium, iron, manganese, strontium ions present in hard water and heavy metals present in Jayasumana et al. Environmental Health 2015, 14:6 Page 8 of 10 http://www.ehjournal.net/content/14/1/6 agrochemicals combine with pesticide structures and re- when compared to those of a previous study done in sist quick degradation within the environment [9]. This 2007 [39]. In that study, the mean age of the male and may be a reason for the gradual increase in hardness female patients with CKDu was 56.7 years and 54.2 years, and objectionable taste in the water of abandoned shal- respectively. A decreasing mean age of patients com- low wells in the endemic areas. pared to a study done 6 years ago supports the notion of If drinking the water contaminated with heavy metals the progressive nature of the disease and the possible and glyphosate, from abandoned wells in the past, and contribution of a cumulative toxin in the pathogenesis now from the currently serving wells, is the only risk of the disease process. factor in operation, then, we can expect to see all inhabi- Smoking, consuming alcohol, chewing betel with or tants in the endemic area- males and females, farmers without tobacco, long-term pain killer (NSAIDs) use and and non-farmers- to be equally affected by the CKDu. family history of death due to CKD were not risk factors As this is not the case, we now have to provide an ex- for developing CKDu in Padavi-Sripura region even in planation as to why the male sex, farming and applying the univariable analysis. Level of education and illicit pesticides increase the risk of developing CKDu by al- alcohol consumption were not significant covariates as- most three fold. The most plausible explanation here is sociated with increased risk of CKDu in Padavi-Sripura. that the risk of CKDu associated with drinking water Smoking and consumption of alcohol by females is cultur- contaminated with heavy metals and pesticides represent ally frowned upon in Sri Lankan society-a phenomenon only the important baseline risk, for both males and fe- that accounts for the results seen this study. males. However, the continued exposure to glyphosate A published study in 2010 demonstrated that, chem- and other pesticides through manual spraying and other ical fertilizers used in Sri Lanka are contaminated with farming activities can augment this baseline risk several cadmium, chromium, uranium and radioactive sub- fold, particularly for the male farmers. Due to the stances [40]. The possibility of cutaneous and respiratory strenuous exertion needed for carrying a 16 L or 20 L absorption of pesticides while working in the field and metal sprayer full of liquid pesticides on their back for long term low level exposure to arsenic, heavy metals, several hours, the spraying function has been exclusively and pesticide residues through drinking water, food, and delegated to the male farmers. This type of manual tobacco have already been documented [2,37]. A study spraying of glyphosate can expose the male farmers to carried out in 12 countries demonstrated significant the pesticide chronically. The presence of significant amount of cadmium in rice cultivated in Sri Lanka [41]. levels of glyphosate in the urine of the farmers and their Tobacco that is chewed with betel by rural farmers in family members several hours after spraying the pesti- Sri Lanka also contains cadmium and other nephrotoxic cide has been well documented [37,38]. In one study the metals [2]. authors attribute these high levels of glyphosate to the The recall bias associated with this case control study, oral and dermal absorption during and immediately after and the selection of controls from community members spraying [38]. Acquavella et al. have demonstrated who came to the hospital for screening can be a draw- that the farmers who do not use Personal Protective back. However, they are from the same community with Equipment (PPE) such as gloves, have five times more the same health anxiety about the CKDu. Ideal controls glyphosate levels in their urine in comparison to those should be based within the community. We have also who use PPE properly [37]. In a focus group discussion not matched the cases and controls. However, we have conducted by two current authors (SG and CW) 16 used stratification in analysis. The selection of cases also farmers from Padavi-Sripura area, admitted that they use was not ideal. They were not newly diagnosed or inci- very little or no PPE in spraying pesticides and wear only dent cases. However, they were diagnosed between 2009 scanty clothing during the process, primarily because of December and April 2012. A patient diagnosed in December 2009 if he or she survives, will be recruited to the unbearable heat in the paddy fields. These farmers also admitted that many of their colleagues do not fol- the study within 30 months of diagnosis. The CKDu pa- low instructions and the specified guidelines for spraying tients have a high mortality and we have studied only survivors with different severity, different prognosis and and often use much higher concentrations of the pesti- cide in the hope of obtaining better results. All of the different stages of the disease. facts stated above can now account for the significantly The in-depth details of lifetime exposure to pesti- cides were not gathered. As rice farming is seasonal, high risk and the associations observed among the male farmers who spray glyphosate. the number of days per year and years of use was not The mean age of the male patients with CKDu was collected. Intensitylevel of pesticideexposurewas also 45.5 years while its 47.4 years in females i.e., it is a dis- not measured along with other details such as the ap- ease of middle- farmers. However, the mean age of the plication method, mixing status, equipment and the both male and female patients were considerably lower use of PPE. Jayasumana et al. Environmental Health 2015, 14:6 Page 9 of 10 http://www.ehjournal.net/content/14/1/6 Conclusions 2. Ministry of Health. Data Presented at the presidential task force for prevention of kidney diseases. Colombo, Sri Lanka: Presidents house; 2014. The current study strongly supports the hypothesis that 3. Jayatilake N, Mendis S, Maheepala P, Mehta FR. Chronic kidney disease of CKDu in Sri Lanka is a drinking-water-related disease in uncertain aetiology: prevalence and causative factors in a developing farmers who have a history of spraying glyphosate. Fur- country. BMC Nephrol. 2013;14:180. 4. Nanayakkara S, Komiya T, Ratnatunga N, Senevirathna STMLD, Harada KH, ther studies should focus the abandoned drinking water Hitomi T, et al. Tubulointerstitial damage as the major pathological lesion in sources in areas with high prevalence of the disease and endemic chronic kidney disease among farmers in North Central Province investigate the link between CKDu and glyphosate in of Sri Lanka. Environ Health Prev Med. 2012;17:213–21. 5. Athuraliya NT, Abeysekera TD, Amerasinghe PH, Kumarasiri R, Bandara P, particular and heavy metals in drinking water. Karunaratne U, et al. Uncertain etiologies of proteinuric-chronic kidney disease in rural Sri Lanka. Kidney Int. 2010;80:1212–21. Abbreviations 6. Wanigasuriya K. Aetiological factors of Chronic Kidney Disease in the North CKDu: Chronic Kidney Disease of unknown etiology; NCP: North Central Central Province of Sri Lanka: A review of evidence to-date. J Coll Comm Province; NSAIDs: Non-Steroidal Anti Inflammatory Drugs; MCPA-2: Physic Sri Lanka. 2012;17:21–42. methyl-4-chlorophenoxyacetic acid; IIRMES: Integrated Research in Materials, 7. Secretary to the Ministry of Health. Chronic Kidney Disease of Unknown Etiology; Environments and Society; CSULB: California State University, Long Beach; Circular no 01-10/2009. Colombo, Sri Lanka: Ministry of Health; 2009. ICP-MS: Inductively Coupled Plasma Mass Spectrometer; SRMs: Standard 8. Jayasena HAH, Chandrajith R, Gangadhara KR. Water management in reference materials; ELISA: Enzyme link immune sorbent assay; HPLC: High ancient Tank Cascade Systems (TCS) in Sri Lanka: Evidence for systematic performance liquid chromatography; PPE: Personal protective equipment. tank distribution. J Geol Soc Sri Lanka. 2011;14:29–34. 9. Jayasumana C, Gunatilake S, Senanayake P. Glyphosate, hard water and Competing interests nephrotoxic metals: Are they the culprits behind the epidemic of chronic The authors declare that they have no competing interests. The founding kidney disease of unknown etiology in Sri Lanka? Int J Environ Res Public sponsors had no role in the design of the study; in the collection, analyses, Health. 2014;11:2125–47. or interpretation of data; in the writing of the manuscript, and in the 10. Rubio F, Veldhuis LJ, Clegg BS, Fleeker JR, Hall JC. Comparison of a direct decision to publish the results. ELISA and an HPLC method for glyphosate determinations in water. J Agric Food Chem. 2003;51:691–6. Authors’ contribution 11. Water Hardness Classification of the United States Geological Survey. Research idea and study design: CJ, PP. data acquisition: CJ, PP, CW, SA, [https://water.usgs.gov/owq/hardness-alkalinity.html] data analysis/interpretation: CJ, SS, SA, SG statistical analysis: SA, SS, 12. Wilks MF, Fernando R, Ariyananda PL, Eddleston M, Berry DJ, Tomenson JA, supervision: SS, SG. Each author contributed important intellectual content et al. Improvement in survival after paraquat ingestion following during manuscript drafting, accepts accountability for the overall work. All introduction of a new formulation in Sri Lanka. PLoS Med. 2008;5:0250–9. authors read and approved the final manuscript. 13. Dawson A, Buckley N. Integrating approaches to paraquat poisoning. Ceylon Med J. 2007;52:45–7. Authors’ information 14. Castro-Gutiérrez N, McConnell R, Andersson K, Pacheco-Antón F, Hogstedt CJ is a lecturer in Pharmacology at Faculty of Medicine, Rajarata University of C. Respiratory symptoms, spirometry and chronic occupational paraquat Sri Lanka (RUSL). He is the Director, National project for the prevention of exposure. Scand J Work Environ Heal. 1997;23:421–7. kidney diseases, Sri Lanka. PP is the chair and professor of Chemistry in the 15. Gawarammana IB, Buckley NA. Medical management of paraquat ingestion. Department of Chemistry, University of Kelaniya, Sri Lanka. SA is the head Br J Clin Pharmacol. 2011;72:745–57. and Senior Lecturer of Community Medicine in Faculty of Medicine, RUSL. 16. Szekacs A, Darvas B. Forty years with glyphosate. In: Hasaneen MN, editor. CW was the Medical officer in charge, Padavi-Sripura government hospital. Herbicides–Properties, Synthesis and Control of Weeds. 1st ed. Croatia: SG is Professor, California State University, Long Beach, USA and a diplomate InTech; 2012. p. 247–84. American board of preventive medicine in occupational medicine. SS is chair 17. Jiraungkoorskul W, Upatham ES, Kruatrachue MSahaphong S, Vichasri-Grams and Professor of Medicine, Faculty of Medicine, RUSL. S, Pokethitiyook P. Biochemical and histopathological effects of glyphosate herbicide on nile tilapia (Oreochromis niloticus). Environ Toxicol. 2003;18:260–7. Acknowledgement The authors wish to acknowledge the assistance provided by Hela Suwaya 18. Ayoola SO. Histopathological effect of glyphosate on Juvenile African Organization, staff in the IIRMES laboratory-CSULB, villagers in Padavi-Sripura, Catfish(Clariasgariepinus). Am Eurasian J Agric Environ Sci. 2008;4:362–7. Professor Mala Amarasinghe, Dr. Kumudu Dahanayake and Dr. Anjana Silva. 19. Séralini GE, Cellier D, De Vendomois JS. New analysis of a rat feeding study Project on Higher Education for Twenty first Century (HETC) of the University with a genetically modified maize reveals signs of hepatorenal toxicity. Arch Grants Commission, Sri Lanka and Farmers Trust fund Government of Sri Environ Contam Toxicol. 2007;52:596–602. Lanka provided the financial support. 20. Tizhe EV, Ibrahim ND, Fatihu MY, Igbokwe IO, George BD. Serum biochemical assessment of hepatic and renal functions of rats during oral Author details exposure to glyphosate with zinc. Comp Clin Path. 2013;22. doi:10.1007/ Department of Pharmacology, Faculty of Medicine, Rajarata University of Sri s00580-013-1740-6. Lanka, Anuradhapura 50008, Sri Lanka. Department of Chemistry, Faculty of 21. Larsen K, Najle R, Lifschitz A, Virkel G. Effects of sub-lethal exposure of rats Science, University of Kelaniya, Colombo, Sri Lanka. Department of to the herbicide glyphosate in drinking water: Glutathione transferase enzyme Community Medicine, Faculty of Medicine, Rajarata University of Sri Lanka, activities, levels of reduced glutathione and lipid peroxidation in liver, kidneys Anuradhapura, Sri Lanka. Government Hospital, Padavi-Sripura, Sri Lanka. and small intestine. Environ Toxicol Pharmacol. 2012;34:811–8. Department of Health Science, California State University Long Beach, Long 22. Krüger M, Schrödl W, Neuhaus J, Shehata AA. Field Investigations of Glyphosate Beach, CA, USA. Department of Medicine, Faculty of Medicine, Rajarata in Urine of Danish Dairy Cows. J Environ Anal Toxicol. 2013;3:1000186. University of Sri Lanka, Anuradhapura, Sri Lanka. 23. Jayawardena UA, Rajakaruna RS, Navaratne AN, Amerasinghe PH. Toxicity of Agrochemicals to Common Hourglass Tree Frog (Polypedates Cruciger) in Received: 19 October 2014 Accepted: 13 January 2015 Acute and Chronic Exposure. Int J Agri Bio. 2010;12:641–8. Published: 18 January 2015 24. Siddharth M, Datta SK, Bansal S, Mustafa M, Banerjee BD, Kalra OP, et al. Study on organochlorine pesticide levels in chronic kidney disease patients: association with estimated glomerular filtration rate and oxidative stress. References J Biochem Mol Toxicol. 2012;26:241–7. 1. Jayasumana MACS, Paranagama PA, Amarasinghe MD, Wijewardane KMRC, Dahanayake KS, Fonseka SI, et al. Possible link of Chronic arsenic toxicity 25. Kaneko K, Chiba M, Hashizume M, Kunii O, Sasaki S, Shimoda T, et al. Renal with Chronic Kidney Disease of unknown etiology in Sri Lanka. J Nat Sci tubular dysfunction in children living in the Aral Sea Region. Arch Dis Child. Res. 2013;3:64–73. 2003;88:966–8. Jayasumana et al. Environmental Health 2015, 14:6 Page 10 of 10 http://www.ehjournal.net/content/14/1/6 26. Whish-Wilson P. The Aral Sea Environmental Health Crisis. J Rurasl Remote Environ Heal. 2002;1:29–34. 27. Kumar RS. Aral Sea: Tragedy Environmental in Central Asia. Econ Polit Wkly. 2002;37:3797–802. 28. Reddy DV, Gunasekar A. Chronic kidney disease in two coastal districts of Andhra Pradesh, India: Role of drinking water. Environ Geochem Health. 2013;35:439–54. 29. Kidney conundrum. [http://www.downtoearth.org.in/content/kidney-conundrum] 30. El Minshawy O. End-stage renal disease in the El-Minia Governorate, upper Egypt: An epidemiological study. Saudi J Kidney Dis Transpl. 2011;22:1048–54. 31. Orantes CM, Herrera R, Almaguer M, Brizuela EG, Hernández CE, Bayarre H, et al. Chronic kidney disease and associated risk factors in the Bajo Lempa region of El Salvador: Nefrolempa study, 2009. MEDICC Rev. 2011;13:14–22. 32. Correa-Rotter R, Wesseling C, Johnson RJ. CKD of unknown origin in Central America: The case for a mesoamerican nephropathy. Am J Kidney Dis. 2014;63(3):506–20. 33. Cotruvo J. Hardness in Drinking Water, Background Document for Development of WHO Guidelines for Drinking Water Quality. Geneva, Switzerland: World Health Organization; 2011. 34. Nalewaja J. Salt antagonism of glyphosate. Weed Sci. 1991;39:622–8. 35. Nalewaja J. Spray carrier salts affect herbicide toxicity to Kochia (Kochiascoparia). Weed Technol. 1993;7:154–8. 36. Sumbramaniam V, Hoggard PE. Metal complexes of glyphosate. J Agric Food Chem. 1998;38:1326–9. 37. Acquavella JF, Alexander BH, Mandel JS, Gustin C, Baker B, Chapman P. Glyphosate biomonitoring for farmers and their families: Results from the farm family exposure study. Environ Health Perspect. 2004;112:321–6. 38. Mesnage R, Moesch C, Grand R, Lauthier G, Vendômois J, Gress S, et al. Glyphosate Exposure in a Farmer’s Family. J of Env Protection. 2012;9:1001–3. 39. Wanigasuriya KP, Peiris-John RJ, Wickremasinghe R, Hittarage A. Chronic renal failure in North Central Province of Sri Lanka: an environmentally induced disease. Trans R Soc Trop Med Hyg. 2007;101:1013–7. 40. Chandrajith R, Seneviratna S, Wickramaarachchi K, Attanayake T, Aturaliya TNC, Dissanayake CB. Natural radionuclides and trace elements in rice field soils in relation to fertilizer application: study of a chronic kidney disease area in Sri Lanka. Environ Earth Sci. 2009;60:193–201. 41. Meharg AA, Norton G, Deacon C, Williams P, Adomako EE, Price A, et al. Variation in rice cadmium related to human exposure. Environ Sci Technol. 2013;47:5613–8. doi:10.1186/1476-069X-14-6 Cite this article as: Jayasumana et al.: Drinking well water and occupational exposure to Herbicides is associated with chronic kidney disease, in Padavi-Sripura, Sri Lanka. Environmental Health 2015 14:6. Submit your next manuscript to BioMed Central and take full advantage of: • Convenient online submission • Thorough peer review • No space constraints or color figure charges • Immediate publication on acceptance • Inclusion in PubMed, CAS, Scopus and Google Scholar • Research which is freely available for redistribution Submit your manuscript at www.biomedcentral.com/submit http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Environmental Health Springer Journals

Drinking well water and occupational exposure to Herbicides is associated with chronic kidney disease, in Padavi-Sripura, Sri Lanka

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Copyright © 2015 by Jayasumana et al.; licensee BioMed Central.
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Environment; Environmental Health; Occupational Medicine/Industrial Medicine; Public Health
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Abstract

Background: The chronic kidney disease of unknown etiology (CKDu) among paddy farmers in was first reported in 1994 and has now become most important public health issue in dry zone of Sri Lanka. The objective was to identify risk factors associated with the epidemic in an area with high prevalence. Methods: A case control study was carried out in Padavi-Sripura hospital in Trincomalee district. CKDu patients were defined using health ministry criteria. All confirmed cases (N = 125) fulfilling the entry criteria were recruited to the study. Control selection (N = 180) was done from people visiting the hospital for CKDu screening. Socio-demographic and data related to usage of applying pesticides and fertilizers were studied. Drinking water was also analyzed using ICP-MS and ELISA to determine the levels of metals and glyphosate. Results: Majority of patients were farmers (N = 107, 85.6%) and were educated up to ‘Ordinary Level’ (N = 92, 73.6%). We specifically analyzed for the effect modification of, farming by sex, which showed a significantly higher risk for male farmerswithOR4.69(95%CI1.06-20.69)incomparisontotheir female counterparts.Inthe multivariableanalysisthe highest risk for CKDu was observed among participants who drank well water (OR 2.52, 95% CI 1.12-5.70) and had history of drinking water from an abandoned well (OR 5.43, 95% CI 2.88-10.26) and spray glyphosate (OR 5.12, 95% CI 2.33-11.26) as a pesticide. Water analysis showed significantly higher amount of hardness, electrical conductivity and glyphosate levels in abandoned wells. In addition Ca, Mg, Ba, Sr, Fe, Ti, V and Sr were high in abandoned wells. Surface water from reservoirs in the endemic area also showed contamination with glyphosate but at a much lower level. Glyphosate was notseeninwater samplesinthe Colombo district. Conclusion: The current study strongly favors the hypothesis that CKDu epidemic among farmers in dry zone of Sri Lanka is associated with, history of drinking water from a well that was abandoned. In addition, it is associated with spraying glyphosate and other pesticides in paddy fields. Farmers do not use personnel protective equipments and wears scanty clothing due to heat when spraying pesticides. Keywords: Chronic Kidney disease, Tubulointerstitial nephritis, Well water, Herbicides, Glyphosate, Sri Lanka Background denote this condition where “u” stands for unknown or A chronic kidney disease (CKD) with unusual character- uncertain etiology. Twenty years after the first report, istics was first reported in 1994 among middle-aged this disease is the most important public health issue in paddy farmers in Padaviya farming colony in the north- NCP with more than 50,000 estimated patients, and eastern boarder of the North Central Province (NCP) of spreading on an epidemic scale to other farming areas in Sri Lanka [1]. Some authors used the term CKDu to the Northern, Eastern, North Western, Central, and Uva provinces of the country [2]. The prevalence of the dis- ease among those aged 15–70 years is estimated at * Correspondence: jayasumanalk@yahoo.com 15.1% in the Anuradhapura district in NCP [3]. The Department of Pharmacology, Faculty of Medicine, Rajarata University of Sri Lanka, Anuradhapura 50008, Sri Lanka unique feature of this CKD epidemic is that its etiology Full list of author information is available at the end of the article © 2015 Jayasumana et al.; licensee BioMed Central. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Jayasumana et al. Environmental Health 2015, 14:6 Page 2 of 10 http://www.ehjournal.net/content/14/1/6 does not link to commonly known risk factors for CKD Selection of controls such as diabetes mellitus, hypertension, and glomerulo- Controls were selected from the same Padavi-Sripura nephritis [3]. area as the cases, and shared the same environment as The CKD patients in this epidemic are asymptomatic the cases. Screening for controls consists of testing for until the later stages of the disease and show tubular serum creatinine and urine microalbumin.180 healthy interstitial nephritis associated with mononuclear cell in- individuals who came to the hospital for screening for filtration with development of glomerular sclerosis and CKDu during the study period were selected as controls tubular atrophy [4]. The characteristic geographical dis- after excluding CKDu and other chronic diseases. Controls tribution of the disease and associated socioeconomic were not matched for age. factors are suggestive of environmental and occupational Medical officers and university academics that were origins. Tubulo-interstitial damage and negative immune- trained collected demographic and risk factor data using fluorescence for IgG, IgM, and complement-3 are more in a pre-designed questionnaire. Age, sex, marital status, favor of a toxic nephropathy [5]. Several research studies education, current and past sources of drinking water, conducted to determine the cause of CKDu, have specu- history of smoking, illicit alcohol usage, chewing betel lated about the causative role of agrochemicals. Toxins and tobacco, chronic use of painkillers-particularly Non- postulated so far as etiological factors include arsenic (As), Steroidal Anti Inflammatory Drugs (NSAIDs), and family cadmium (Cd), nephrotoxic pesticides and fluoride [1,2,6]. history of death due to CKD were collected. The partici- However, none of the studies performed so far has focused pants’ place of residence and the predominant occupa- on the link between the disease and the exact type of tion during the last ten years were recorded. The pesticides used. The objective of this study was to identify information on whether the participants are presently the major risk factors associated with the CKDu in the drinking from well, tap, spring or water from reservoirs Padavi-Sripura area in Sri Lanka. was collected. They were also asked about source of drinking water used previously (during the last ten years) Methods and specifically probed about history of drinking water Study setting from a well that is currently abandoned. This was be- Sripura is a divisional secretariat of Trincomalee district of cause water from some wells has become distasteful over the Eastern province bordering to NCP with a population time and people have stopped drinking from these wells of 11,858. This area has been identified as having one of (abandoned wells). These wells were defined as aban- the highest prevalence of CKDu. Authors carried out a doned wells for the purpose of this study. case control study to determine the association between A detailed history of applying fertilizer (which is usu- CKDu and selected socio-demographic factors, and a ally performed manually with bare hands) and pesticides number of variables related to the use of agrochemicals. (done with hand held sprayers) was obtained. The type of pesticide most widely used during the respondent’s Selection of cases entire lifetime was also recorded. The use of organo- All patients (125) with CKDu were recruited from the phospates, paraquat, 2-methyl-4-chlorophenoxyacetic patients who attended a medical clinic at Padavi-Sripura acid (MCPA), glyphosate, bispyribac, carbofuran, man- divisional hospital in Sri Lanka. Cases were defined as cozeb and other commonly used pesticides were cat- subjects diagnosed with CKD and defined as CKDu ac- egorically identified. As many farmers did not recognize cording to the criteria defined by the Sri Lanka Ministry the type of pesticide by their chemical name a list of com- of Health [7]. monly available trade names were used to collect the data. These multiple brands were later lumped together based 1. No past history of, or current treatment for, diabetes upon their chemical name. Ethical clearance for the study mellitus or chronic and/or severe hypertension, was obtained from the ethics review committee of the Fac- history of snakebite, urological disease of known ulty of Medicine, Rajarata University of Sri Lanka. Written etiology or glomerulonephritis. informed consent was obtained from all participants. 2. Normal Glycosylated Hemoglobin level (HbA1C˂6.5%). Water analysis 3. Blood Pressure ˂160/100 mmHg untreated or ˂140/ Water samples were collected at 34 wells in Padavi- 90 mmHg on up to two antihypertensive agents. Sripura and two reservoirs (Padaviya wewa and Jayanthi wewa). Padaviya wewa (2357 ha) was built in 5th century The patients with CKDu were referred to the consult- A.C and was renovated in 11 century A.C and in 1956. ant nephrologist and the diagnosis was confirmed. All Jayanthi wewa belongs to the cascade system of Padaviya confirmed cases of CKDu was recruited. Data collection wewa [8]. Water samples were also collected from two started in April 2012 and ended in October 2012. wells and three different locations of mainline pipe born Jayasumana et al. Environmental Health 2015, 14:6 Page 3 of 10 http://www.ehjournal.net/content/14/1/6 water from Colombo district, a non-endemic area for The analytical detection limit was calculated as the CKDu. Also a sample of water from a domestic reverse concentration of the element which gave a detectable osmosis (RO) machine in Padavi-Sripura was collected. signal above the background noise at greater than the 18 of the wells tested at Padavi-Sripura were abandoned 99% confidence level, and the detection limit was calcu- or not used for drinking. 200 mL polyethylene bottles lated as the mean of blanks plus 3 times the standard were decontaminated by repeated soaking in 2 M nitric deviation of the mean. acid (24 h) and were used for water collection. Following the collection of samples, bottle were bagged and then Detection of glyphosate stored in a cooler box. All bottles were refrigerated We decided to measure glyphosate because two current (under 4°C) and subsequently transported in a cooler authors have formulated and published a detailed hy- box to the Institute for Integrated Research in Materials, pothesis that incriminates glyphosate that chelates with Environments and Society (IIRMES) lab, California State heavy metals as a causative factor for CKDu and also con- University, Long Beach (CSULB), USA where they were tributing to water hardness [9]. Enzyme-immunoassay in analyzed. We measured mono and polyvalent cations in the analysis of glyphosate in water is a cost effective and the water to test a hypothesis about heavy metals and reliable method. ELISA method has a lower detection elements contributing to water hardness as a possible limit of glyphosate (0.6 μg/L) compared to HPLC method cause in CKDu [9]. (50 μg/L) although there was no statistically significant difference between two methods [10]. ICP MS analysis Water samples were tested for glyphosate by Enzyme- Major and trace elements were measured using an In- immunoassay using commercial test kits (US Biocontract ductively Coupled Plasma Mass Spectrometer (ICP-MS; Inc., San Diego, CA) according to the manufactures proto- HP 4500, Agilent Technologies, Palo Alto, CA) equipped col. This test is based on the competition between the with a quadrupole analyzer and octopole collision/reac- glyphosate and glyphosate-horseradish peroxidase con- tion cell that can be pressurized with either a hydrogen jugate for binding to the rabbit antibody raised against (H ) or helium (He) reaction gas. Sample was injected glyphosate. Validation of the ELISA test was done in com- at the rate of 0.4 mL/min using a peristaltic pump. parison with GC-MS. To study the recovery rate several Carrier Argon (Ar) gas at rate of 1.2 L/min through samples were spiked with 10 μg/L of glyphosate and it was a Babbington-style nebulizer was introduced into a measured in the supernatant by using ELISA. Peltier-cooled double-pass spray-chamber at 2°C. The 1.0 L/min auxiliary Ar and 12.0 L/min plasma gas Ar Data analysis were added for a total of 14.2 L/min separated from Associations were investigated with frequency tables. nickel cones. The ICP-MS was tuned under standard Continuous variables were summarized by means and settings by running the manufacturer's recommended standard deviations. Categorical variables were dichoto- tuning solution containing 10 μg/L of Li, Y, Ce, Tl, mized for analyses. Odds ratios (OR), 95% confidence inter- and Co (Agilent internal standard mix) for resolution vals, and p-values were obtained to assess the association and sensitivity. Interference levels were reduced by between exposure and developing CKDu. Data were ana- optimizing plasma conditions to produce low oxide lyzed using SPSS (version 22). and doubly charged ions (formation ratio of <1.0%) and residual matrix interferences were removed using the collision/reaction processes in the Octopole Reaction Results System. Of the 125 diagnosed CKDu patients, significantly higher number (n = 89, 71.2%) was male. The mean age of male Accuracy, precision and detection limits (45.51 ± 19.78 years) and female (47.45 ± 17.51 years) pa- Accuracy was measured using the spiked standard solu- tients did not show any significant difference. Majority tions (Agilent Technologies). Ultrapure water (MilliQ) of the CKDu patients included in the study had educa- was used as blank (1 blank per each 10 sample batch). tion up to ordinary level (n = 92, 73.6%) and were Precision (reproducibility) was ascertained using farmers (n = 107, 85.6%). Only nine (7.2%) CKDu pa- within-day replicate analysis of samples. The Relative tients reported death of a close family member due to Standard Deviation (%RSD = SD/χ of the replicate CKD. Of the CKDu patients, 86 (96.6%) males were values X 100%; χ is mean value) was calculated to give farmers compared to 21 (58.3%) females. Controls in- an indication of sample preparation and analytical pre- cluded 180 healthy individual presented to the study site cision. Replicates of each day provided an indication for screening for CKDu. This included 98 (54.4%) males of within-day precision. and 82 (45.6%) females. Jayasumana et al. Environmental Health 2015, 14:6 Page 4 of 10 http://www.ehjournal.net/content/14/1/6 Factors associated with CKDu High conductance indicates high concentration of In the univariable analysis (Table 1), male sex (OR 2.07, dissolved-solids. This can affect the palatability of 95% CI 1.27-3.36), engaging in farming related activities water. Conductivity was highest among the abandoned (OR 3.12, 95% CI 1.74-5.61), pesticide application (OR wells. Content of iron in abandoned wells was also sig- 3.31, 95% CI 2.04-5.36), applying fertilizers (OR 2.37, nificantly high. 95% CI 1.43-3.93), drinking well water (OR 4.82, 95% CI Glyphosate (Gly) concentration also showed a marked 2.27-10.24) and a history of drinking from recently aban- difference between serving and abandoned wells doned well (OR 6.93, 95% CI3.87-12.40) was significantly (Table 3). All the abandoned wells except for one associated with CKDu. We specifically analyzed for the (94%) contained more than 1 μg/L of glyphosate where effect modification of, farming by sex, which showed a as among the serving wells only 31% contained gly- significantly higher risk for male farmers with OR 4.69 phosate above the 1 μg/L level. There was trace (95% CI 1.06-20.69) in comparison to their female coun- amounts of glyphosate in the surface water in two res- terparts. CKDu was associated with life time exposure to ervoirs indicate the glyphosate may have been washed different kinds of pesticides considered in this study ex- off from the agricultural or paddy lands. However gly- cept carbofuran. Glyphosate, a total weed killer, was the phosate was not seen in well or mainline pipe borne most widely used pesticide among farmers in both water in Colombo district. groups. In general, subjects who sprayed glyphosate were four times more likely to have CKDu compared to those Discussion without such a history. The present study revealed that male farmers from In the multivariable analysis, we investigated the un- Padavi-Sripura, who spray glyphosate, drink well water confounded effect of individual exposure factors after and had history of drinking from an abandoned well, are adjustment for age, sex, educational level, having a death at a significantly higher risk of developing CKDu. This among family members due to CKD and other exposure association is evident even after adjusting for all the factors related to agrochemical use. Drinking well water baseline and exposure variables. This is the first study in (OR 2.52, 95% CI 1.12-5.70), history of drinking from re- Sri Lanka that analyses the association of CKDu among cently abandoned well (OR 5.43, 95% CI 2.88-10.26) and farmers with the type of pesticide and most widely used use of glyphosate 5.12 (2.33-11.26) were the factors sig- pesticide during their lifetime. nificantly associated with CKDu. A significant difference The only pesticide not associated with CKDu in uni- between groups has been detected with related to pesti- variable analysis is carbofuran an insecticide in granular cide application (OR 2.34: 95% CI 0.97- 5.57) however, form. All other pesticides considered in this study are in perhaps with a smaller sample size, this difference would liquid form and easily absorbable through skin and by have proved to be not statistically significant. inhalation, particularly during manual spray. Paraquat was a common herbicide used by the paddy farmers since 1960s [12]. However, it was phased out gradually Analysis of drinking water samples due to 400 to 500 deaths per year in Sri Lanka due to its There was a significant difference between abandoned use for committing suicide [13]. Paraquat also can cause (not used for drinking now) and serving wells (presently respiratory, skin and mucosal irritation among those used for drinking) in total permanent hardness (calcu- who spray it [14]. In 2010 pesticide technical advisory lated value using calcium and magnesium). Barium, iron committee of Sri Lanka decided to ban the use of para- and strontium were significantly high in abandoned quat for paddy cultivation [15]. wells (Table 2). The ban on paraquat prompted most farmers to According to the classification by United States switch to using glyphosate as an alternative herbicide. Geological Survey on water hardness [11], all the other There are no immediate symptoms among sprayers of abandoned wells were classified as having very high glyphosate. However, there are important differences be- hardness except for two. However, none of the cur- tween these two pesticides. Paraquat is a contact herbi- rently serving wells can be classified as such and be- cide but glyphosate is a trans-locating herbicide with longs to either moderately hard or hard category of anti-microbial action that softens the earth, paving the water hardness. Surface water from Padaviya reservoir way for ‘till-less’ farming [16]. Glyphosate came to the had very low hardness (i.e. soft) that was similar to the market in 1971 but there are no details of when it was well water and mainline pipe borne water in the first available in Sri Lanka. However, it has become most Colombo district. In parallel, calcium, magnesium, bar- widely used pesticide in Sri Lanka [9]. The amount of ium and strontium levels for water in non-endemic glyphosate imported was 5.3 million kg and this repre- Colombo district was also low in comparison to the sents more than half (52%) of the total pesticides (in- endemic area. cluding all other herbicides, insecticides, and fungicides) Jayasumana et al. Environmental Health 2015, 14:6 Page 5 of 10 http://www.ehjournal.net/content/14/1/6 Table 1 The distribution the demographic variables and other risk factors, by CKDu outcome CKDu Patients (Cases) N = 125(%) Non CKD (Controls) N = 180 (%) Unadjusted OR (95% CI) p-value Gender Male 89 (71.2) 98 (54.4) 2.07 (1.27-3.36) 0.0031* Female 36 (18.8) 82 (45.6) Education Up to OL 92 (73.6) 147 (81.7) 0.64 (0.37-1.10) 0.1041 Higher education 33 (26.4) 33 (18.3) Farming Yes 107 (85.6) 118 (65.6) 3.12 (1.74-5.61) < 0.0001* No 18 (14.4) 62 (34.4) Pesticide application Yes 86 (68.8) 72 (40.0) 3.31 (2.04-5.36) <0.0001* No 39 (31.2) 108 (60.0) Applying Fertilizer Yes 95 (76.0) 103 (57.2) 2.37 (1.43-3.93) < 0.0001* No 30 (24.0) 77 (42.8) Drinking well water Yes 116 (92.8) 131 (72.8) 4.82 (2.27-10.24) < 0.0001* No 9 (7.2) 49 (27.2) History of drinking water from abandoned well Yes 58 (46.4) 20 (11.1) 6.93 (3.87-12.40) < 0.0001* No 67 (53.6) 160 (88.9) Smoking Yes 36 (28.8) 37 (20.6) 1.56 (0.92-2.66) 0.0970 No 89 (71.2) 143 (79.4) Illicit alcohol Yes 17 (13.6) 21 (11.7) 1.19 (0.60-2.36) 0.6150 No 108 (86.4) 159 (88.3) Betel chewing Yes 106 (84.8) 152 (84.4) 1.03 (0.55-1.94)0.9326 No 19 (15.2) 28 (15.6) Tobacco with betel chewing Yes 92 (73.6) 129 (71.7) 1.10 (0.66-1.84) 0.7101 No 33 (26.4) 51 (28.3) Long term pain killer use Yes 10 (8.0) 15 (8.3) 0.96 (0.42-2.20) 0.9169 No 115 (92.0) 165 (91.7) Family history of death due to CKD Yes 9 (7.2) 13 (7.2) 1.00 (0.41- 2.41) 0.9941 No 116 (92.8) 167 (92.8) Ever used Organophosphate Yes 54 (43.2) 54 (30.0) 1.77 (1.10-2.86) 0.0183* No 71 (56.8) 126 (70.0) Ever used Paraquat Yes 64 (51.2) 53 (29.4) 2.51 (1.56-4.04) 0.0001* Jayasumana et al. Environmental Health 2015, 14:6 Page 6 of 10 http://www.ehjournal.net/content/14/1/6 Table 1 The distribution the demographic variables and other risk factors, by CKDu outcome (Continued) No 61 (48.8) 127 (70.6) Ever used MCPA Yes 56 (44.8) 56 (31.1) 1.80 (1.12-2.88) 0.0152* No 69 (55.2) 124 (68.9) Ever used Glyphosate Yes 82 (65.6) 55 (30.6) 4.33 (2.66-7.05) <0.0001* No 43 (34.4) 125 (69.4) Ever used Bispyribac Yes 64 (51.2) 62 (34.4) 2.00 (1.25-3.18) 0.0037* No 61 (48.8) 118 (65.6) Ever used Carbofuran Yes 46 (36.8) 51 (28.3) 1.47 (0.91-2.40) 0.1192 No 79 (63.2) 129 (71.7) Ever used Mancozeb Yes 46 (36.8) 51 (28.3) 1.94(1.21-3.13) 0.0062* No 79 (63.2) 129 (71.7) *P < 0.05. imported in 2012 [9]. There are no studies that report increases the risk of getting CKDu with people who nephrotoxic properties of glyphosate on humans. used glyphosate having the highest risk. However, several animal studies provide evidence for Certain pesticides are known to be associated with nephrotoxic properties of glyphosate [17-22]. Toxicity CKDu in humans. A study done in India demonstrated of glyphosate to common hourglass tree frog in Sri that there was a significant correlation between plasma Lanka is previously reported [23]. levels of organochlorine and decrease in GFR and the de- Byspiribac which is another weed killer also in- velopment of CKD [24]. Internationally, the use of organo- creases the risk of CKDu. Organophosphate com- chlorine and arsenical pesticides at cotton fields in the pounds and moncozeb, are the leading insecticide and Aral Sea area which caused an epidemic of tubular kidney fungicide respectively, used by the farmers in the damage and abnormal increase of non-communicable dis- Padavi-Sripura area. The use of all these pesticides eases in central-Asia, is considered to be one of the world’s Table 2 Hardness and related parameters in drinking water samples mg/L μg/L mg/L μs/cm Well type Na K Ca Mg Ba Sr Hardness Condutivity Abandoned wells in Sripura (n = 18) Mean 74.8 0.9 51.8 28.0 150.7 572.4 243.6 877.2 Median 57.1 0.8 53.2 29.6 142.3 519.0 234.5 623.0 Serving wells in Sripura (n = 16) Mean 51.9 0.6 29.0 13.0 89.4 269.1 125.9 465.0 Median 38.6 0.7 28.5 11.6 83.9 265.0 121.0 509.5 U 77.5 97.0 26.5 24.5 64.0 31.0 6.0 44.0 Z −2.295 −1.629 −4.054 −4.124 −2.760 −3.899 −4.762 −3.450 P Value .0217* .1034 .0001** .0000** 0.0058** .0001** .0000** .0006** Surface water 5.85 0.45 10.6 1.15 10.4 46 31.2 79.5 RO water 3.1 0.2 0.6 0.6 2.1 4.6 4.0 22.0 Colombo well 2.6 0.7 6.8 0.8 16.4 13.1 20.2 49 Colombo main 2.5 0.7 6.8 0.8 16.5 14.5 20.0 49 *P < 0.05, **P < 0.01, # two sample Wilcoxan rank-sum (Mann–Whitney) test. Jayasumana et al. Environmental Health 2015, 14:6 Page 7 of 10 http://www.ehjournal.net/content/14/1/6 Table 3 Trace metal and glyphosate content in drinking water samples Abandoned wells Serving wells U Z P value Surface Ro Colombo Colombo water water well tap Mean Median Mean Median Al 2.2 1.0 2.9 2.2 117.5 −0.916 0.3596 3.5 <0.1 6.7 71.6 Sb 3.2 0.9 4.5 2.9 127.0 −0.587 0.5570 3.4 0.1 0.3 0.5 As 0.8 0.4 0.3 0.3 104.5 −1.381 0.1674 0.2 0.2 <0.5 <0.1 Cd 0.04 0.0 0.04 0.0 138.0 −0.247 0.8051 0.1 0.1 0.1 0.1 Cr 1.0 0.6 0.5 0.0 103.0 −1.495 0.1348 0.3 0.4 <0.1 <0.1 Co 0.07 0.1 0.2 0.1 118.0 −0.968 0.3329 0.1 <0.1 0.1 0.2 Cu 1.4 1.2 1.9 1.0 107.5 −1.264 0.2063 0.4 3.5 0.3 0.4 Fe 90.5 76.6 45.2 40 60.0 −2.898 0.0038** 20.0 1.5 17.4 26.1 Pb 0.5 0.1 0.2 0.1 124.0 −0.791 0.4287 0.1 0.2 0.1 0.1 Mn 2.8 1.1 2.0 0.3 98.5 −1.573 0.1156 0.8 0.4 5.5 6.4 Mo 1.5 1.4 1.1 0.8 97.5 −1.609 0.1077 0.3 1.0 0.3 0.4 Ni 0.8 0.7 3.1 0.6 140.0 −0.139 0.8897 0.3 0.8 0.1 0.2 Se 0.7 0.7 0.3 0.2 65.5 −2.731 0.0063** 0.4 0.3 <0.1 <0.1 Ag 0.01 0.0 0.02 0.0 133.5 −0.736 0.4615 <0.1 0.1 <0.1 0.1 Tl 0.1 0.1 0.05 0.0 129.0 −0.582 0.5603 0.1 0.1 <0.1 <0.1 Sn 0.3 0.3 0.3 0.3 143.0 −0.038 0.9696 0.3 0.2 0.3 0.3 Ti 0.8 0.8 0.6 0.7 85.5 −2.047 0.0406* 0.2 0.3 0.3 0.3 V 14.4 10.5 17.4 6.3 84.5 −2.053 0.0400* 1.4 0.8 0.3 0.3 Zn 4.3 2.3 7.7 3.4 115.0 −1.001 0.3168 6.8 6.1 0.8 0.7 Gly 3.5 3.2 0.7 0.6 15.0 −4.456 0.0000** 0.05 ND ND ND *P < 0.05, **P < 0.01, # two sample Wilcoxan rank-sum (Mann–Whitney) test, Glyphosate. greatest ecological disasters [25-27]. Moreover, a CKDu and zinc also contribute to the hardness in water but epidemic very similar to that of Sri Lanka has been identi- not shown here in the calculation of traditional hardness fied in agricultural communities in Andra and Odisha, [33]. These metals contribute to the increased dissolved two southeastern provinces of India [28,29], upper Egypt solids and enhanced conductivity of the water. Unpalat- [30] and predominantly among young male farm workers ability and the inability to use it for cooking purposes in the pacific coastal region of Central American countries may have driven people to abandon these wells. These of El Salvador, Nicaragua, and Costa Rica [31,32]. Similar conditions have made it necessary for the residents in to Sri Lankan and Indian scenarios the etiology of CKDu the endemic area to travel longer distances to obtain in Mesoamerica is not linked to the most frequently water from the currently serving wells, which are be- known causes such as diabetes mellitus and hypertension. coming lesser in numbers as more and more wells get Drinking water previously from an abandoned well in- abandoned due to increasing hardness. Most of the resi- creases the risk of developing CKDu almost seven times dents indicate that the hardness and the objectionable in univariable analysis. Drinking well water and having a taste are on the increase even in the currently serving history of drinking water from a well abandoned within wells in comparison to the surface water. The poor taste the last 10 years are significant predictors of CKDu. The and the scarcity of the water itself may cause people in abandoning of certain shallow wells in which water has the Padavi-Sripura to drink less water thus contributing previously been used for drinking purposes is a common to further dehydration and deteriorating renal function. phenomenon in the CKDu endemic area. Long-term Organic compounds in the water also can contribute to- residents in this area complain that the ground water wards the taste of water. The unknown factor here is hardness has been steadily increasing over the last two glyphosate. Do the pesticides contribute to the water decades rendering the water increasingly unpalatable taste? Another aspect of these herbicides (glyphosate, and not suitable for cooking. bispyribac, MCPA, and paraquat) is that they process Hardness of water from abandoned wells is associated one or more carboxyl groups that are capable of retain- with the presence of metals such as calcium and magne- ing metals [34-36]. Calcium, Magnesium and Strontium sium. Aluminum, barium, iron, manganese, strontium ions present in hard water and heavy metals present in Jayasumana et al. Environmental Health 2015, 14:6 Page 8 of 10 http://www.ehjournal.net/content/14/1/6 agrochemicals combine with pesticide structures and re- when compared to those of a previous study done in sist quick degradation within the environment [9]. This 2007 [39]. In that study, the mean age of the male and may be a reason for the gradual increase in hardness female patients with CKDu was 56.7 years and 54.2 years, and objectionable taste in the water of abandoned shal- respectively. A decreasing mean age of patients com- low wells in the endemic areas. pared to a study done 6 years ago supports the notion of If drinking the water contaminated with heavy metals the progressive nature of the disease and the possible and glyphosate, from abandoned wells in the past, and contribution of a cumulative toxin in the pathogenesis now from the currently serving wells, is the only risk of the disease process. factor in operation, then, we can expect to see all inhabi- Smoking, consuming alcohol, chewing betel with or tants in the endemic area- males and females, farmers without tobacco, long-term pain killer (NSAIDs) use and and non-farmers- to be equally affected by the CKDu. family history of death due to CKD were not risk factors As this is not the case, we now have to provide an ex- for developing CKDu in Padavi-Sripura region even in planation as to why the male sex, farming and applying the univariable analysis. Level of education and illicit pesticides increase the risk of developing CKDu by al- alcohol consumption were not significant covariates as- most three fold. The most plausible explanation here is sociated with increased risk of CKDu in Padavi-Sripura. that the risk of CKDu associated with drinking water Smoking and consumption of alcohol by females is cultur- contaminated with heavy metals and pesticides represent ally frowned upon in Sri Lankan society-a phenomenon only the important baseline risk, for both males and fe- that accounts for the results seen this study. males. However, the continued exposure to glyphosate A published study in 2010 demonstrated that, chem- and other pesticides through manual spraying and other ical fertilizers used in Sri Lanka are contaminated with farming activities can augment this baseline risk several cadmium, chromium, uranium and radioactive sub- fold, particularly for the male farmers. Due to the stances [40]. The possibility of cutaneous and respiratory strenuous exertion needed for carrying a 16 L or 20 L absorption of pesticides while working in the field and metal sprayer full of liquid pesticides on their back for long term low level exposure to arsenic, heavy metals, several hours, the spraying function has been exclusively and pesticide residues through drinking water, food, and delegated to the male farmers. This type of manual tobacco have already been documented [2,37]. A study spraying of glyphosate can expose the male farmers to carried out in 12 countries demonstrated significant the pesticide chronically. The presence of significant amount of cadmium in rice cultivated in Sri Lanka [41]. levels of glyphosate in the urine of the farmers and their Tobacco that is chewed with betel by rural farmers in family members several hours after spraying the pesti- Sri Lanka also contains cadmium and other nephrotoxic cide has been well documented [37,38]. In one study the metals [2]. authors attribute these high levels of glyphosate to the The recall bias associated with this case control study, oral and dermal absorption during and immediately after and the selection of controls from community members spraying [38]. Acquavella et al. have demonstrated who came to the hospital for screening can be a draw- that the farmers who do not use Personal Protective back. However, they are from the same community with Equipment (PPE) such as gloves, have five times more the same health anxiety about the CKDu. Ideal controls glyphosate levels in their urine in comparison to those should be based within the community. We have also who use PPE properly [37]. In a focus group discussion not matched the cases and controls. However, we have conducted by two current authors (SG and CW) 16 used stratification in analysis. The selection of cases also farmers from Padavi-Sripura area, admitted that they use was not ideal. They were not newly diagnosed or inci- very little or no PPE in spraying pesticides and wear only dent cases. However, they were diagnosed between 2009 scanty clothing during the process, primarily because of December and April 2012. A patient diagnosed in December 2009 if he or she survives, will be recruited to the unbearable heat in the paddy fields. These farmers also admitted that many of their colleagues do not fol- the study within 30 months of diagnosis. The CKDu pa- low instructions and the specified guidelines for spraying tients have a high mortality and we have studied only survivors with different severity, different prognosis and and often use much higher concentrations of the pesti- cide in the hope of obtaining better results. All of the different stages of the disease. facts stated above can now account for the significantly The in-depth details of lifetime exposure to pesti- cides were not gathered. As rice farming is seasonal, high risk and the associations observed among the male farmers who spray glyphosate. the number of days per year and years of use was not The mean age of the male patients with CKDu was collected. Intensitylevel of pesticideexposurewas also 45.5 years while its 47.4 years in females i.e., it is a dis- not measured along with other details such as the ap- ease of middle- farmers. However, the mean age of the plication method, mixing status, equipment and the both male and female patients were considerably lower use of PPE. Jayasumana et al. Environmental Health 2015, 14:6 Page 9 of 10 http://www.ehjournal.net/content/14/1/6 Conclusions 2. Ministry of Health. Data Presented at the presidential task force for prevention of kidney diseases. Colombo, Sri Lanka: Presidents house; 2014. The current study strongly supports the hypothesis that 3. Jayatilake N, Mendis S, Maheepala P, Mehta FR. Chronic kidney disease of CKDu in Sri Lanka is a drinking-water-related disease in uncertain aetiology: prevalence and causative factors in a developing farmers who have a history of spraying glyphosate. Fur- country. BMC Nephrol. 2013;14:180. 4. Nanayakkara S, Komiya T, Ratnatunga N, Senevirathna STMLD, Harada KH, ther studies should focus the abandoned drinking water Hitomi T, et al. Tubulointerstitial damage as the major pathological lesion in sources in areas with high prevalence of the disease and endemic chronic kidney disease among farmers in North Central Province investigate the link between CKDu and glyphosate in of Sri Lanka. Environ Health Prev Med. 2012;17:213–21. 5. Athuraliya NT, Abeysekera TD, Amerasinghe PH, Kumarasiri R, Bandara P, particular and heavy metals in drinking water. Karunaratne U, et al. Uncertain etiologies of proteinuric-chronic kidney disease in rural Sri Lanka. Kidney Int. 2010;80:1212–21. Abbreviations 6. Wanigasuriya K. Aetiological factors of Chronic Kidney Disease in the North CKDu: Chronic Kidney Disease of unknown etiology; NCP: North Central Central Province of Sri Lanka: A review of evidence to-date. J Coll Comm Province; NSAIDs: Non-Steroidal Anti Inflammatory Drugs; MCPA-2: Physic Sri Lanka. 2012;17:21–42. methyl-4-chlorophenoxyacetic acid; IIRMES: Integrated Research in Materials, 7. Secretary to the Ministry of Health. Chronic Kidney Disease of Unknown Etiology; Environments and Society; CSULB: California State University, Long Beach; Circular no 01-10/2009. Colombo, Sri Lanka: Ministry of Health; 2009. ICP-MS: Inductively Coupled Plasma Mass Spectrometer; SRMs: Standard 8. Jayasena HAH, Chandrajith R, Gangadhara KR. Water management in reference materials; ELISA: Enzyme link immune sorbent assay; HPLC: High ancient Tank Cascade Systems (TCS) in Sri Lanka: Evidence for systematic performance liquid chromatography; PPE: Personal protective equipment. tank distribution. J Geol Soc Sri Lanka. 2011;14:29–34. 9. Jayasumana C, Gunatilake S, Senanayake P. Glyphosate, hard water and Competing interests nephrotoxic metals: Are they the culprits behind the epidemic of chronic The authors declare that they have no competing interests. The founding kidney disease of unknown etiology in Sri Lanka? Int J Environ Res Public sponsors had no role in the design of the study; in the collection, analyses, Health. 2014;11:2125–47. or interpretation of data; in the writing of the manuscript, and in the 10. Rubio F, Veldhuis LJ, Clegg BS, Fleeker JR, Hall JC. Comparison of a direct decision to publish the results. ELISA and an HPLC method for glyphosate determinations in water. J Agric Food Chem. 2003;51:691–6. Authors’ contribution 11. Water Hardness Classification of the United States Geological Survey. Research idea and study design: CJ, PP. data acquisition: CJ, PP, CW, SA, [https://water.usgs.gov/owq/hardness-alkalinity.html] data analysis/interpretation: CJ, SS, SA, SG statistical analysis: SA, SS, 12. Wilks MF, Fernando R, Ariyananda PL, Eddleston M, Berry DJ, Tomenson JA, supervision: SS, SG. Each author contributed important intellectual content et al. Improvement in survival after paraquat ingestion following during manuscript drafting, accepts accountability for the overall work. All introduction of a new formulation in Sri Lanka. PLoS Med. 2008;5:0250–9. authors read and approved the final manuscript. 13. Dawson A, Buckley N. Integrating approaches to paraquat poisoning. Ceylon Med J. 2007;52:45–7. Authors’ information 14. Castro-Gutiérrez N, McConnell R, Andersson K, Pacheco-Antón F, Hogstedt CJ is a lecturer in Pharmacology at Faculty of Medicine, Rajarata University of C. Respiratory symptoms, spirometry and chronic occupational paraquat Sri Lanka (RUSL). He is the Director, National project for the prevention of exposure. Scand J Work Environ Heal. 1997;23:421–7. kidney diseases, Sri Lanka. PP is the chair and professor of Chemistry in the 15. Gawarammana IB, Buckley NA. Medical management of paraquat ingestion. Department of Chemistry, University of Kelaniya, Sri Lanka. SA is the head Br J Clin Pharmacol. 2011;72:745–57. and Senior Lecturer of Community Medicine in Faculty of Medicine, RUSL. 16. Szekacs A, Darvas B. Forty years with glyphosate. In: Hasaneen MN, editor. CW was the Medical officer in charge, Padavi-Sripura government hospital. Herbicides–Properties, Synthesis and Control of Weeds. 1st ed. Croatia: SG is Professor, California State University, Long Beach, USA and a diplomate InTech; 2012. p. 247–84. American board of preventive medicine in occupational medicine. SS is chair 17. Jiraungkoorskul W, Upatham ES, Kruatrachue MSahaphong S, Vichasri-Grams and Professor of Medicine, Faculty of Medicine, RUSL. S, Pokethitiyook P. Biochemical and histopathological effects of glyphosate herbicide on nile tilapia (Oreochromis niloticus). Environ Toxicol. 2003;18:260–7. Acknowledgement The authors wish to acknowledge the assistance provided by Hela Suwaya 18. Ayoola SO. Histopathological effect of glyphosate on Juvenile African Organization, staff in the IIRMES laboratory-CSULB, villagers in Padavi-Sripura, Catfish(Clariasgariepinus). Am Eurasian J Agric Environ Sci. 2008;4:362–7. Professor Mala Amarasinghe, Dr. Kumudu Dahanayake and Dr. Anjana Silva. 19. Séralini GE, Cellier D, De Vendomois JS. New analysis of a rat feeding study Project on Higher Education for Twenty first Century (HETC) of the University with a genetically modified maize reveals signs of hepatorenal toxicity. Arch Grants Commission, Sri Lanka and Farmers Trust fund Government of Sri Environ Contam Toxicol. 2007;52:596–602. Lanka provided the financial support. 20. Tizhe EV, Ibrahim ND, Fatihu MY, Igbokwe IO, George BD. Serum biochemical assessment of hepatic and renal functions of rats during oral Author details exposure to glyphosate with zinc. Comp Clin Path. 2013;22. doi:10.1007/ Department of Pharmacology, Faculty of Medicine, Rajarata University of Sri s00580-013-1740-6. Lanka, Anuradhapura 50008, Sri Lanka. Department of Chemistry, Faculty of 21. Larsen K, Najle R, Lifschitz A, Virkel G. Effects of sub-lethal exposure of rats Science, University of Kelaniya, Colombo, Sri Lanka. Department of to the herbicide glyphosate in drinking water: Glutathione transferase enzyme Community Medicine, Faculty of Medicine, Rajarata University of Sri Lanka, activities, levels of reduced glutathione and lipid peroxidation in liver, kidneys Anuradhapura, Sri Lanka. Government Hospital, Padavi-Sripura, Sri Lanka. and small intestine. Environ Toxicol Pharmacol. 2012;34:811–8. Department of Health Science, California State University Long Beach, Long 22. Krüger M, Schrödl W, Neuhaus J, Shehata AA. Field Investigations of Glyphosate Beach, CA, USA. Department of Medicine, Faculty of Medicine, Rajarata in Urine of Danish Dairy Cows. J Environ Anal Toxicol. 2013;3:1000186. University of Sri Lanka, Anuradhapura, Sri Lanka. 23. Jayawardena UA, Rajakaruna RS, Navaratne AN, Amerasinghe PH. Toxicity of Agrochemicals to Common Hourglass Tree Frog (Polypedates Cruciger) in Received: 19 October 2014 Accepted: 13 January 2015 Acute and Chronic Exposure. Int J Agri Bio. 2010;12:641–8. Published: 18 January 2015 24. Siddharth M, Datta SK, Bansal S, Mustafa M, Banerjee BD, Kalra OP, et al. Study on organochlorine pesticide levels in chronic kidney disease patients: association with estimated glomerular filtration rate and oxidative stress. References J Biochem Mol Toxicol. 2012;26:241–7. 1. Jayasumana MACS, Paranagama PA, Amarasinghe MD, Wijewardane KMRC, Dahanayake KS, Fonseka SI, et al. Possible link of Chronic arsenic toxicity 25. Kaneko K, Chiba M, Hashizume M, Kunii O, Sasaki S, Shimoda T, et al. Renal with Chronic Kidney Disease of unknown etiology in Sri Lanka. J Nat Sci tubular dysfunction in children living in the Aral Sea Region. Arch Dis Child. Res. 2013;3:64–73. 2003;88:966–8. Jayasumana et al. Environmental Health 2015, 14:6 Page 10 of 10 http://www.ehjournal.net/content/14/1/6 26. Whish-Wilson P. The Aral Sea Environmental Health Crisis. J Rurasl Remote Environ Heal. 2002;1:29–34. 27. Kumar RS. Aral Sea: Tragedy Environmental in Central Asia. Econ Polit Wkly. 2002;37:3797–802. 28. Reddy DV, Gunasekar A. Chronic kidney disease in two coastal districts of Andhra Pradesh, India: Role of drinking water. Environ Geochem Health. 2013;35:439–54. 29. Kidney conundrum. [http://www.downtoearth.org.in/content/kidney-conundrum] 30. El Minshawy O. End-stage renal disease in the El-Minia Governorate, upper Egypt: An epidemiological study. Saudi J Kidney Dis Transpl. 2011;22:1048–54. 31. Orantes CM, Herrera R, Almaguer M, Brizuela EG, Hernández CE, Bayarre H, et al. Chronic kidney disease and associated risk factors in the Bajo Lempa region of El Salvador: Nefrolempa study, 2009. MEDICC Rev. 2011;13:14–22. 32. Correa-Rotter R, Wesseling C, Johnson RJ. CKD of unknown origin in Central America: The case for a mesoamerican nephropathy. Am J Kidney Dis. 2014;63(3):506–20. 33. Cotruvo J. Hardness in Drinking Water, Background Document for Development of WHO Guidelines for Drinking Water Quality. Geneva, Switzerland: World Health Organization; 2011. 34. Nalewaja J. Salt antagonism of glyphosate. Weed Sci. 1991;39:622–8. 35. Nalewaja J. Spray carrier salts affect herbicide toxicity to Kochia (Kochiascoparia). Weed Technol. 1993;7:154–8. 36. Sumbramaniam V, Hoggard PE. Metal complexes of glyphosate. J Agric Food Chem. 1998;38:1326–9. 37. Acquavella JF, Alexander BH, Mandel JS, Gustin C, Baker B, Chapman P. Glyphosate biomonitoring for farmers and their families: Results from the farm family exposure study. Environ Health Perspect. 2004;112:321–6. 38. Mesnage R, Moesch C, Grand R, Lauthier G, Vendômois J, Gress S, et al. Glyphosate Exposure in a Farmer’s Family. J of Env Protection. 2012;9:1001–3. 39. Wanigasuriya KP, Peiris-John RJ, Wickremasinghe R, Hittarage A. Chronic renal failure in North Central Province of Sri Lanka: an environmentally induced disease. Trans R Soc Trop Med Hyg. 2007;101:1013–7. 40. Chandrajith R, Seneviratna S, Wickramaarachchi K, Attanayake T, Aturaliya TNC, Dissanayake CB. Natural radionuclides and trace elements in rice field soils in relation to fertilizer application: study of a chronic kidney disease area in Sri Lanka. Environ Earth Sci. 2009;60:193–201. 41. Meharg AA, Norton G, Deacon C, Williams P, Adomako EE, Price A, et al. Variation in rice cadmium related to human exposure. Environ Sci Technol. 2013;47:5613–8. doi:10.1186/1476-069X-14-6 Cite this article as: Jayasumana et al.: Drinking well water and occupational exposure to Herbicides is associated with chronic kidney disease, in Padavi-Sripura, Sri Lanka. Environmental Health 2015 14:6. Submit your next manuscript to BioMed Central and take full advantage of: • Convenient online submission • Thorough peer review • No space constraints or color figure charges • Immediate publication on acceptance • Inclusion in PubMed, CAS, Scopus and Google Scholar • Research which is freely available for redistribution Submit your manuscript at www.biomedcentral.com/submit

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Environmental HealthSpringer Journals

Published: Jan 18, 2015

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