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GEOLOGY, ECOLOGY, AND LANDSCAPES 2021, VOL. 5, NO. 3, 199–208 INWASCON https://doi.org/10.1080/24749508.2019.1705644 RESEARCH ARTICLE Determination of local background and baseline values of elements within the soils of the Birimian Terrain of the Wassa Area of Southwest Ghana Raymond Kazapoe and Emmanuel Arhin Department of Earth Science, University for Development Studies, Navrongo, Ghana ABSTRACT ARTICLE HISTORY Received 24 September 2019 This study establishes the local background and baseline values of elements in surface soils in Accepted 12 December 2019 Wassa area underlain by Birimian rocks using probability Q–Q plots. In this study, a total of 2868 soil samples were collected. The chemical elements in these samples were analysed by XRF KEYWORDS technique. The results from the analysis were processed following Papastergios and Karim Geochemistry; Background; methods that normalized and transformed the data after which a best of ﬁt is estimated to Baseline; Environment; determine the background and baseline values. The method excludes the outliers at the Surface soil; Ghana extremities from the transformed data until the distribution follows a straight line. The method yielded the following background values in this study: 6.41 mg/kg for As, 52.55 mg.kg for Cr, 9.89 mg/kg for Pb, 10.21 mg/kg for Co and 17.18 mg/kg for Ni. The calculated baseline values were also 13.2 mg/kg, 80.7 mg/kg, 6.7 mg/kg, 6.4 mg/kg and 8.7 mg/kg for As, Cr, Pb, Co and Ni, respectively. The departure between the locally calculated background and baseline values of elements relative to worldwide accepted background and baseline values suggests the rele- vance to conduct such studies for the various geological provinces in the country as a vital step to properly and eﬀectively manage and sustain the environment against environmental health diseases. Introduction researchers either use World Health Organization (WHO) values or worldwide acceptable values instead The elements in soils have been identiﬁed as vital com- of locally established background and baseline values. ponents of the environment because they can be hazar- Background values are determined by the composition dous or essential to human health. Translocation of of the underlying rock as well as the weathering pro- these elements in soils to food chains may impact on cesses prevalent in the area and are considered as the human health. Monitoring and managing the impacts normal values of potentially polluting substances pre- of the natural environment on public health require the sent in natural soils without human inﬂuence establishment of environmental background and base- (Matschullat, Ottenstein, & Reimann, 2000). It has line values as this will guide in outlining the environ- been argued that rocks have a large inﬂuence on ele- mental risk areas. The background values provide ment contents in soils, with concentrations sometimes a guide to ascertain the presence of anthropogenic lower and above critical values (Salonen & Korkka- eﬀects that could lead to hazardous or beneﬁcial con- Niemi, 2007). However, it is almost impossible to sequences. In environmental geochemistry and health, establish natural background levels, i.e., the geochem- the background is considered as the natural concentra- ical composition of virgin soils, since atmospheric tion in environmental material devoid of human inﬂu- deposition can contaminate soils with certain trace ences. It is distinguished from environmental baseline elements (Cicchella et al., 2005, Albanese, 2014). But values that refer to the natural variations in the con- from Riemann and de Caritat (2005) human activity is centration of an element in the surface environment, at a key determinant of the level of element concentra- a determined place and time. This concept includes tions in soils. Ordinarily, places such as industrial and natural geographic concentrations (background level) residential areas are often considered as environments and the diﬀuse anthropogenic contribution in soils at higher risk of anthropogenic inﬂuences on elemen- (Kobierski & Dabkowska-Naskret, 2012). The Impact tal soil concentrations. Relatively, Alloway (2013) of this may be deleterious or beneﬁcial. recognized less modiﬁed and undisturbed areas such It is unclear if Ghana has its own background and as forests and subsistent farmlands are mainly consid- baseline values to monitor and manage the impact of ered as close to pristine zones with minimal pollution. the natural environment on public health issues. The Based on Alloway’s assertion, the establishment of available testimonies in this discipline suggest other- local background and baseline values for diﬀerent wise because earth science and public health CONTACT Raymond Kazapoe email@example.com Department of Earth Science, University for Development Studies, Navrongo, Ghana This article has been republished with minor changes. These changes do not impact the academic content of the article. © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group on behalf of the International Water, Air & Soil Conservation Society(INWASCON). 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 cited. 200 R. KAZAPOE AND E. ARHIN geological domains is critical due to the variations in within the soils found in the Birimian terrain of the the modal composition of rocks from place to place Wassa area using probability plots (Q–Q plots) as an and the numerous environmental activities. The important step towards in environmental studies and detection of the human-induced contamination in an management in Ghana. environment is properly assessed using the baseline value, which is uncommon in Ghana. The most com- Location, demography and population of monly used method of determining human inﬂuences study area on soils in works done in Ghana relies on the use of continental crustal averages and worldwide accepted The study area forms part of geological ﬁeld sheet values, which have been proven to be problematic 0503B of Ghana and covers Asankragwa, Akropong, (Arhin, Mouri, & Kazapoe, 2017). The present spate Samreboi and Bogosu, within the Wassa traditional of illegal mining and infrastructural developments area (Figure 1). The area has an estimated population coupled with population growth in Ghana makes it of 282 000 according to the 2000 National population challenging to identify undisturbed soils or virgin census (Ghana Statistical Service, 2002). The main soils. Example, illegal mining and logging, conversion occupation of the population is farming; primarily the of farmlands to residential areas tend to suggest the cultivation of food and cash crops like plantain cassava, destruction of precinct lands hence calculated local cocoa, coﬀee and rubber. Small-scale artisanal gold background values if not expressed as a range may mining and the illegal artisanal gold mining, popularly be problematic. The variable nature of element con- known as “Galamsey” are not uncommon in the area. centrations due to underlying geology, geological pro- Aside from the large-scale Wassa Mine operated by cesses and anthropogenic chemical contribution due Golden Star gold at Bogoso, there are medium scale to human activities results in variable element con- mining activities at Jukwa and Akropong. The area tents. The present research sees the inappropriateness lacks any impactful industries despite the presence of of just using the natural concentrations to establish the a few exploration companies whose activities are at the pollution status at a place because of the numerous various stages of exploratory work. The study area was processes inﬂuencing the landscape modiﬁcations. selected on the basis of the diverse rocks present in the Rather, both background and baseline values calcu- area. It represents a typical example of the Birimian lated should be determined separately for each ele- terrain which covers a good portion of the West of ment in geologically diﬀerent regions; otherwise, the Ghana. Soil samples used as part of this study were limit values for contaminated soils may be lower than taken from relatively undisturbed areas within the the natural concentrations (background levels) calcu- study area with minimal mining activities and from lated for an extensive area (Gałuszka, 2007). The fac- a deep horizon so as to be representative of the local tors that inﬂuence the soil trace element content are background and baseline values of the area. very variable. This thus makes the use of normative values of environmental legislation of other countries Physiographic and geological settings or regions or global values inappropriate, as they must be determined locally. Currently, published studies The area is predominantly undulating with the highest that have determined the concentrations and patterns points averaging about 150 m. Draining the area are of the spatial distribution of heavy metals in soils for the Tano and Ankobra Rivers. The climate is tropical virgin soils appear insuﬃcient or patchy. It was also humid with two rainfall patterns. The major rainfall unclear whether the reported work done in this dis- occurs from March to July and the minor season cipline considered geology as the source of the ele- occurs from September to early December and ments in the soils. Geological sciences reveal that Average annual rainfall is 173 mm. The vegetation in diﬀerent geological domains present diﬀerent arrays the area has been inﬂuenced by the rainfall pattern. of rock units and hence local backgrounds and base- The temperature ranges from 29°C to 24°C between line values computed for diﬀerent geological domains March and August, respectively. will diﬀer in values. Therefore, to ensure eﬀective The area is underlain by rocks of Birimian System environmental management policies based on back- and lies within the southern portion of the Ashanti ground and baseline values, local background and Greenstone Belt, along the eastern margin within baseline values must be determined for the diﬀerent a volcano-sedimentary assemblage located close to geological domains. Although a lot of studies have the Tarkwaian formation contact. A fault zone to the determined the concentration of metals and metal- east separates the Tarkwaian Formation of rock units loids in similar areas, there are no categorical studies from the Volcano-sedimentary rocks of the Sefwi which determine baseline and background concentra- group (Parra-Avila et al., 2015). The lithological tions for a speciﬁc geological province in Ghana. This sequence of the study area is characterized by study, therefore, attempts to establish the local back- a sequence of meta-volcanic (basaltic to andesitic pro- ground and baseline concentrations of elements toliths) ﬂows intercalated with metasedimentary rocks GEOLOGY, ECOLOGY, AND LANDSCAPES 201 Figure 1. Location of the study area. such as greywacke, magnetite-rich argillite and rare Results obtained from the XRF analysis were black shale layers, micaschists and felsic porphyry. The interpreted using descriptive statistical analysis. area is also intruded by granitoids and some maﬁc Information such as standard deviation, standard intrusives. Most of the granitoids correspond to typi- error, and mean for the various elements were cal tonalite-trondhjemite-granodiorite (TTG) suites calculated. All the variables were transformed (Perrouty et al., 2016). Rocks are aggregates of miner- using normal score transformation prior to the als, implying that after weathering diﬀerent types of principal component analysis (PCA), followed by elements will be released into the soils and depending the cluster analysis using a furthest neighbourhood on their concentrations may impact on the health of method. The relationshipsofelementsinsoilsam- the exposed populations. ples were presented in a component matrix and aDendrogram. The data normalities for As, Co, Pb, Cr, Pb, Ni, Mg, Materials and methods Fe, K and Mn were examined using one-sample Kolmogorov–Smirnov test (the K–S test of normality) A total of 2868 soil samples were collected, dried, and as well as the Shapiro–Wilk tests. The normalised data sieved to <106 µm fraction for elemental analysis. The was then log-transformed to achieve near straight line soil samples were conducted on a 1 km grid using distribution using Q–Q plot. Outliers that were GARMIN E-TREX 30 GPS device to navigate to the noticed in the upper and lower extreme corners for predetermined sampling points. The top 20 cm depth the Q–Q plots of the various elements were excluded of the soil was collected as a sample from a 30 cm until the distribution followed a straight line (extreme nominal diameter hole. The samples collected were high and low values, respectively). This was repeated put in labelled Plastic bags. Sample weights of 2 kg until the best ﬁtness to the straight line was achieved were collected at all sample stations. The collected following the methodology by Papastergios, samples were sent to a commercial laboratory for Fernandez-Turiel, Georgakopoulos, and Gimeno chemical analysis using XRF technique on pressed (2010) and Karim, Qureshi, and Mumtaz (2015). pellets except for gold that was analysed using Fire The Q–Q plot supported the delimiting three classes Assay. The elements analysed included As, K, Co, Cr, that included geochemical background, baseline, and Mn, Ni, Pb, Mg, Fe and Au. geochemical anomalies on the basis of their geometric 202 R. KAZAPOE AND E. ARHIN mean (g) and geometric deviations (d) following the Table 2. The ﬁve classes determined after Papastergios et al. (2011). computation as demonstrated by Papastergios, Class Concentration Fernandez-Turiel, Filippidis, and Gimeno (2011) and Negative Anomaly <g/d Papastergios et al. (2010)(Table 2). The analytical qual- Background g/d-gd ity was assessed by inserting quality control and assur- Baseline g Low Anomaly gd-gd ance samples SARM 1, SARM 2 and AMIS 17 for 2 3 Intermediate Anomaly gd -gd accuracy analysis. High Anomaly >gd g = geometric mean, d = geometric deviation. Determined after Papastergios et al. (2011) Results and discussions (McLennan & Murray, 1999). Considering the mea- Quality control and assurance analysis performed on the three certiﬁed reference materials SARM 1, SARM 2 sured average to be consistent for the entire area, the Fe uptake as a dietary supplement may be deﬁcient and AMIS 17 shown in Table 1 displayed no apparent hence cases of anaemia may be predominant. Rose, signs of contamination with precision and bias recorded primarily below 9.3%. The recovery rates for the certi- Hawkes, and Webb (1979)alsoidentiﬁed the median value for Fe as 2.1% in soils. In this study, 2.9% was ﬁed reference material (known also as standard sample) obtained for the median with a very low standard varied between 87.5% and 120% (Table 1). This is deviationof1.7.The dataforFemeanthatcertain considered satisfactory for the study relating the calcu- areas will be deﬁcientinFewhilstsomeareasmay lated recovery rates in a similar study in Rio Doce Basin have enough Fe in soils to support the dietary sup- in Brazil (Guevara et al., 2018). plementation through cultivated food in some areas. The summary statistics developed from the 2868 Another essential element that supports over 300 sample results processed to establish the local back- enzymic reactions Mg had maximum values of 1.52 ground and baseline values are presented in Table 2. wt. % and a mean of 0.19 wt. %. The upper continen- From Table 2, As averages at 17.36 14 mg/kg with tal crust had an average of 50.1% (Wedepohl, 1995). a standard deviation of 15.54. This is not very high This is several percentages higher than the maximum suggesting clustered As spread. Meanwhile, the range measured in this study; suggesting the entire area is is between 2 and 246 mg/kg meaning toxic and deﬁ- deﬁcientinMg. TheprevalenceofMg-deﬁciency cient As concentrations coexist contemporaneously. diseases will be common and require immediate pub- Toxic concentration of 246 mg/kg will pose lic health action. Mn concentration in the area ranges a debilitating eﬀect to the exposed population and from 69.00 to 2600 mg/kg, with a median value of thus required environmental monitoring to locate 159 mg/kg. The average from Table 2 is 203.84 mg/kg and deﬁne such terrains. However, comparing the but the mean Mn content of 8354 world soils was measured average values with local background and reported as 761 mg/kg by Ure and Berrow (1982) baseline values that factor element contributions from with a range of <1–18,300 mg/kg. It is clear from the local activities, chemical and surface process may Table 2 that the measured average from this study is be useful. Co values ranged from a maximum of much lower than the accepted average of 761 mg/kg 43.28 mg/kg to a minimum of 2.64 mg/kg with an in soils. Mn again is deﬁcient and may, therefore, be average value of 4.84 mg/kg (Table 2). Cr recorded a problem for those who require Mn as a dietary a maximum value of 1500 mg/kg and a minimum supplement from food. value of 12 mg/kg, the mean Cr value measured in The deﬁciencies and toxicities of essential metals in this study seems lower than the allowable global limit ma set for Cr worldwide (i.e., 200 mg/kg). jor oxides and trace elements make it an important The essential element Fe component in the oxide priority to establish local backgrounds and baseline for ranges from 14.94 wt. % – 0.44 wt. % with a mean some toxic and essential elements due to the variability in value of 3.22 wt. % (Table 2). This average is lower local environments. Also, from Figure 2,the rescaled than expected in river sediments measured as 4.8% cluster Dendrogram deﬁned four clusters that showed Table 1. Summary statistics of major and trace elements in soil samples in the study area (Unit measurements, mg/kg). Elements Min Mean Median Standard Deviation Skewness Kurtosis Geometric Mean Geometric Standard Deviation Max As 2 17.36 14 15.54 5.09 48.72 4.31 1.26 246 Cr 12 89.52 81 55.03 12.68 288.12 80.74 1.54 1500 Pb 5 7.43 6 4.93 10.82 250.07 6.70 1.48 148 Co 2.64 4.84 3.96 2.75 3.53 33.02 6.44 1.58 43.28 Fe 4 3.22 2.9 1.7 1.57 4.8 2.82 1.69 0.44 K 0.05 0.77 0.76 0.35 0.56 0.86 0.68 1.72 2.92 Mg 0.01 0.19 0.18 0.1 2.92 22.16 0.1 1.68 1.52 Mn 69 203.84 159 152.84 5.96 62.4 176.78 1.68 2600 Ni 2 10.97 9 8.62 4.68 57.02 1.98 8.67 174 GEOLOGY, ECOLOGY, AND LANDSCAPES 203 Figure 2. Dendrogram using a complete linkage to deﬁne element associations in soils. the various elemental associations. SiO in Cluster 1 is is controlled predominantly by chemical weathering. detached from all the other chemicals (Figure 2). This This weathering type will decompose the rocks and the means that soils with more quartz may contain less sulphide minerals (including arsenopyrite) associated content of the other minerals implying the SiO may be with the auriferous quartz veins possibly explaining the from the hydrothermal quartz veins reported by Kesse adsorption of As by various minerals, such as iron and (1985), Adjimah et al. (1993)and Griﬃsetal. (2000)that aluminium oxides, and clay minerals common in tropical are associated with the Birimian System of Ghana. Most soils. The high As averages obtained for Bogoso of these veins host gold mineralization and hence Akropong and Asankragwa conﬁrms As occurrence as become the target for the artisanal small-scale miners. an accessory mineral in gold ore deposits particularly In their quest to mine the auriferous quartz veins facil- hosted in the metasedimentary and volcanoclastic rocks itate the spread of the elements released from the under- of Ghana (Kesse, 1985). The geochemical variations lying rocks through weathering and erosion. Cluster 2 across the landscape as shown in Table 3 suggest the contains Th, Ti, U, and Ba, which occur as oxides, often need to calculate local background and baseline values considered as resistant minerals, unsusceptible to weath- not just for geochemical anomaly detection but for envir- ering and tend to enrich the secondary environment onmental health management towards the attainment of (Cornu et al., 1999;Scheinost, 2005). The MgO, CaO, sustainable development goal on wellbeing and good Zn,Mn, Cr,Ni, V, Fe,and Al areassigned Cluster3, health for all. The knowledge of the local background which was ascribed to the underlying geology. Lead (Pb) and baseline concentrations of elements in speciﬁcareas and Cu occurred with the sulphide minerals and these are essential for environmental studies on health are linked to the auriferous quartz veins deposited as part (Salminen & Tarvainen, 1997). of the hydrothermal deposit in this area (Kesse, 1985, Adjimah et al., 1993, Griﬃs et al., 2000). Similarly, the Sr, Background and baseline calculations and their Na O, Rb, and K O assigned in one group (cluster 20) 2 2 usefulness in environmental health monitoring may mainly occur in the mineral lattices. The dissocia- tion of the metalloid As (in a single cluster) from other Papastergios et al. (2011)method(Table 3)was used to elements suggests its special feature in the environment. calculate the background and baseline values and other It is possible that As has a weak relation to the underlying variables useful in assessing element impacts in the rocks, but may be found in hydrothermal veins common environments is presented in Table 3. The background in the metasedimentary and volcanoclastic rocks similar values expressed as a range in this study (Table 5) to Pb and Cu in this area (Kesse, 1985). The deep weath- appear to have values diﬀerent from continental crustal ering resulting in thick regolith proﬁles at the study area values calculated by Taylor (1964) and Rudnick et al. 204 R. KAZAPOE AND E. ARHIN Table 3. Recovery rates for the various elements. SARM 1 SARM 2 NCSDC 73,334 NCSDC 73,310 BLANK AMIS 17 ELEMENTS AVG CRM RR AVG CRM RR AVG CRM RR AVG CRM RR AVG CRM RR AVG CRM RR As 2.8 2.6 107 19.2 18.4 104 496.9 492.1 101 110 109.6 100 2.7 2.87 94 4.3 3.9 109 Cr 21 18.5 112 23 22.8 101 31 29.5 105 Fe 2.72 2.6 104 3.31 3.1 106 1.36 1.28 106 6.54 7.1 91 MgO 0.4 0.45 88 0.07 0.04 143 1.32 1.05 120 0.52 0.7 65 0.51 0.31 139 19.51 20 97 Pb 8.8 9 98 39.3 37.2 105 500.4 499.8 100 296 298 99 25.7 26.1 98 42.3 43 98 *AVG = Average *CRM = Certiﬁed Reference Material *RR = Recovery Rate No certiﬁed values are available for the areas left blank (2003). The disparities in local background values and not be accurate for the study area and will result in the continental crustal values may lead to diﬀerent speculative conclusions that may be detrimental to predictions and hence a promulgation of unreliable human health particularly for the toxic elements. environmental policies Example the application of The safest approach is to use the calculated baseline using Table 3 in calculating the background value; values in the study because it incorporates element placed As baseline value at 13.29 in this study compared concentrations in both precinct and contaminated with the global As values ranging between 10 mg/kg and soils. The calculated baseline values for As and Cr in 15 mg/kg. The calculated As value though falls within the study shown in Table 6 appear to be in a similar As worldwide As range but show great contrast between in column 2 and Cr in column 4.All others are diﬀer- Webb et al. (1979), Zhu, Williams, and Meharg (2008) ent because of the diﬀerent environmental activities and Italian reference values for soils for Arsenic. The and variations in the underlying geology forming the contrast in background/baseline values from diﬀerent soils. From Table 4 and using Sinclair's Experiential geographic locations from the established local back- model (1991), the background limits for As, Cr, Pb, Co ground/baseline values could lead to several detrimental and Ni in soils for the study area were 6.41 mg/kg, outcomes to expose people in the aﬀected areas. For 52.55 mg/kg, 9.89 mg/kg, 10.21 mg/kg and 17.18 mg/ instance, if As background is set at 20 mg/kg (Table 6)it kg, respectively, for the Birimian of Southwest Ghana. will lead to an outbreak of As-related diseases because The choice of these background values incorporated the people eat what they grow. The authors anticipate the global accepted values for these elements and the the contrast between the calculated local baseline values consequences thereof when toxic elements particularly with the existing globally accepted values to bring some exceeded these accepted global values. distortions in environmental policies. This thus may A background value ranging between 4.1 and inﬂuence strategies to remediate health issues linked 10.2 mg/kg and a baseline value of 6.4 mg/kg was to excess toxic elements or depleted essential elements. determined for Co. This indicates that 1437 samples From Table 6 no single calculated baseline value is the (50.1% of the 2868 samples) belong to the background same for diﬀerent geographic locations for the ele- class. These values are below the normal Co range of ments. It meant the adaptation of worldwide accepted 100 mg/kg for maﬁc rocks and 1 mg/kg −15 mg/kg for values or WHO accepted values may be tricky because acidic rocks (Kabata-Pendias, 2010). Weathering the controls on element concentrations depend on the mechanisms that transform and distribute Co in soils underlying geology, local environmental activities, soil- are very complex due to their diﬀering oxidation states forming processes, geochemical, chemical and physical and also the prevalent microbial activities (Ma & processes. Similarly, if we compare the baseline values Hooda, 2010). The baseline value for Co is 8.0 mg/ with crustal averages (Table 5) the likely conclusion is kg. This, however, is higher than the measured base- As and Cr contaminations with depletions of Pb, Co line value of 6.44 mg/kg in the study. Cobalt acts as and Ni in surface soils. It is therefore imperative that a bio-essential trace element for bacteria, plants, and using upper continental crustal (UCC) averages as humans in the natural environment. The low baseline a baseline to monitor environmental health issues may value calculated implies inadequate Co supplies to −1 Table 4. Geochemical background and anomaly threshold values (mg Kg /wt%). Min Negative Anomaly Background Baseline Low Anomaly Intermediate Anomaly High Anomaly Max As 2.00 6.41 6.41–27.56 13.29 27.56–57.14 57.14–118.47 176.67 246 Cr 12.00 52.55 52.55–124.06 80.74 124.06–190.62 190.62–292.88 6519.23 1500 Pb 5.00 4.54 4.54–9.89 6.70 9.89–14.59 14.59–21.54 44.86 148 Co 4.00 4.07 4.07–10.21 6.44 10.21–16.16 16.16–25.60 41.52 65 Fe 0.44 1.67 1.67–4.76 2.82 4.76–8.02 8.02–13.53 7.95 14.94 K 0.05 0.39 0.39–1.16 0.68 1.16–2.00 2-3.44 0.46 2.92 Mg 0.01 0.06 0.06–0.17 0.10 0.17–0.29 0.29–0.49 0.01 0.92 Mn 70.00 110.00 110.00–281.60 176.00 280-450 450-730 31,249 2600 Ni 2.00 4.38 4.38–17.18 8.67 17.18–34.04 34.04–67.43 75.21 174 GEOLOGY, ECOLOGY, AND LANDSCAPES 205 Table 5. Comparison of estimated background values (milli- of 176 mg/kg. This shows that 2117 samples, repre- grams per kg of dry weight) with the continental crustal senting 73.8% of the total 2868 samples collected, fall averages. within the background class. Other studies revealed Element This Study Continental crustal average Mn to be among the most abundant trace elements in As 6.41–27.56 1.8 the environment (Caballero, Trugo, & Finglas, 2003). Cr 52.55–124.06 100 Pb 4.54–9.89 12.5 The human body has been identiﬁed to contain Co 4.07–10.21 25 12–20 mg of Mn, of which most of it is found in the Ni 4.38–17.18 75 liver, bones and kidneys. It is thus needed for normal skeletal growth and development. It is also essential Table 6. Comparison of estimated baseline values (milligrams for glucose utilization, lipid synthesis and lipid meta- per kg of dry weight) with the values published in the bolism, cholesterol metabolism, pancreatic function literature. and development, as well as prevention of sterility. Element 1 2 3 4 5 Manganese is again important for protein and nucleic As 13.29 14 9.92 9.4 20 acid metabolism; it thus activates enzyme functions Cr 80.74 36 100.56 79.3 150 Pb 6.69 - 33.05 19.5 100 and also involved the thyroid hormone synthesis. Co 6.44 - 22.62 9 20 Deﬁciency of Mn results in; fatness, ataxia, blood Ni 8.67 - 31.97 19.45 120 clotting, skin problems, lowered cholesterol levels, 1 = This study 2 = Jiangxi Geochemical Survey (1987) skeleton disorders, birth defects, reduced immune 3 = Webb et al. 1978 function, impaired glucose metabolism, changes of 4 = Soil background in Taihu, China (Zhu et al., 2008) 5 = Italian reference values for soils, D. LGS 152/2006 hair colour and neurological symptoms. Obtaining the correct baseline values for these elements for the local area may help in developing a workable environ- mental policy that may reduce the incessant environ- plants and humans. This thus makes environmental mental health issues in the study area. monitoring of Co still important because Co concen- Other trace elements considered in this study tration levels can reach hazardous levels in humans as included K and Cr. Background value for K was deter- its bioaccumulation may damage vital organs such as mined as 0.39 wt.% −1.16 wt.% with the corresponding the lever, kidney, pancreas, and heart (Czarnek, baseline of 0.68 wt.% (6800 ppm). The analyses with Terpiłowska, & Siwicki, 2015; Lange et al., 2017). respect to the background value showed about 73.2% Magnesium recorded a background value ranging samples out of the total collected samples to be within between 0.062 wt. % – 0.173 wt. % with a baseline of the background class. Since it is an essential mineral 0.103 wt. %. From Mg data set, 2094 samples (i.e., 73% micronutrient that acts as an intracellular ion for all of the 2868 samples collected) have values in the back- types of cells; the low concentrations in soils may impact ground class. The source of Mg measured in the sam- on the population if their source of dietary supplement is ples may be from the ferromagnesian-rich rocks viafood.Italsoplaysaroleinthe maintenanceof ﬂuid reported by Kesse (1985) to underlie the area. and electrolyte balance. A dietary survey in the US indi- Magnesium notably is essential for human develop- cated the average dietary K intake is about 2,300 mg/day ment. Its toxic eﬀects to humans are yet to be deﬁned. for adult women and 3,100 mg/day for adult men. However, its deﬁciency has an association with Diseases related to K-deﬁciency may not aﬀect the popu- numerous diseases (Rude, Singer, & Gruber, 2009; lation and there will not be the need for K-supplemented Whang, 1987). The calculated average-Mg value is pills to make up for K-deﬁciency in the US. But the same low. In such circumstances, dietary Mg from food might not be said about the study area where most areas will be a challenge from a dietary source. The net eﬀect have K-concentrations in the background class. may be an outbreak of Mg-related diseases. Similarly, Correspondingly, Cr had a background value between background values established for Fe ranged from 1.67 52.5 mg/kg- 124.1 mg/kg with a baseline value of wt. %-4.76 wt. % and a baseline of 2.82wt%. The data 80.7 mg/kg. From the chromium data 2037 samples on Fe show that 1989 samples (i.e., 69.4% of the 2868 (71% of the 2868 samples) belong to the background samples collected) belong to the background class. class. Cr contents similar to these values are associated Iron is an essential element that controls the oxygen- with acidic and argillaceous rocks (Kabata-Pendias, carrying haemoglobin and myoglobin at a suitable 3+ 2010). Most soil Cr exists as Cr and is marginally dosage. Anaemia is associated with Fe-deﬁciency, 6+ mobile in very limited acidic media. Cr has been while the Fe-excesses are related to Fe-overload, 3+ reported to be toxic for plants and animals whiles Cr which could cause hemochromatosis, liver, heart, in certain doses has a detrimental eﬀect for the biochem- and pancreatic damages, and diabetes (Siah, Ombiga, ical activity of soils (Shrivastava, Upreti, Seth, & Adams, Trinder, & Olynyk, 2006). Chaturvedi, 2002). There are Cr-related diseases which In addition to the discussed elements, the back- can be evaluated for geographic area relative to the ground values recorded for Mn ranged from 110 mg/ calculated baseline value of Cr. kg- 281.6 mg/kg with a corresponding baseline value 206 R. KAZAPOE AND E. ARHIN Ni calculated background value in the study 6.41 mg/kg for As, 52.55 mg/kg for Cr, 9.89 mg/kg for ranged from 4.4 mg/kg- 17.2 mg/kg and Pb, 10.21 mg/kg for Co and 17.18 mg/kg for Ni. The a calculated baseline value of 8.7 mg/kg. A total calculated baseline values for As, Cr, Pb, Co and Ni of 1992 samples (i.e., representing 69.5% of the were 13.2 mg/kg, 80.7 mg/kg, 6.7 mg/kg, 6.4 mg/kg 2868 samples collected) belong to the Ni back- and 8.7 mg/kg, respectively. The inconsistencies in ground class. As seen in the study, the distribution calculated background and baseline values relative to of Ni is similar to Fe and Co. Ni occurrence in the the worldwide values further underscore the need to area may be associated with the underlying sul- conduct environmentally health-related studies. The phide-associated rocks (Figure 2). authors conclude that local background and baseline Another known toxic element Pb reported value application to establish hotspots and cold-spots a background value ranging from 4.5 to 9.9 mg/kg of disease-causing elements as a vital step in environ- and a baseline of 6.7 mg/kg. The data set shows mental health management. that 82.7% of the samples ﬁt the background class of Pb. The low Pb values obtained in the study could be the primary Pb in the underlying rocks Acknowledgments hencesourceisgeogenic. Whilst thehighPbassays The appraised soil geochemical data were obtained from recorded in the area may be associated with the European Development Fund (EDF) Project 8-ACP-GH chalcophile element corridors in the underlying -027 carried out in Ghana between the government of rocks or from human-induced activities. Some con- Ghana and the European Union. The authors greatly appreciate the funds released for the project. The support tributions might come from the Light Industries in kind from members of the International Medical Geology where vehicle fumes, oil spillages and vehicle bat- Association (IMGA), Ghana Chapter served as a source of teries can introduce Pb into the environment. motivation to the authors to complete this investigation. We Elsewhere, Pb concentration levels exceeding humbly appreciate your kind contributions and hope you 100 mg/kg was linked to industrial pollution in will encourage others who want to address environmental health issues via medical geology research. Our indebted countries such as Japan and Great Britain (Bellis, thanks are extended to all the reviewers for their helpful Satake, Noda, Nishimura, & McLeod, 2002;Markus comments and suggestions. &McBratney, 2001) A comparison of the baseline values calculated in this study with the average crustal values and similar Disclosure statement works conducted shows that the baseline value of Co is relatively low (Table 5 and Table 6).Thebaseline No potential conﬂict of interest was reported by the authors. valueofCriscomparablewithvaluescalculated for Taihu in China and slightly lower than the average crustal value for Cr. The calculated baseline for Ni in ORCID this study is relatively low compared with the average Raymond Kazapoe http://orcid.org/0000-0002-0307- crustal value and other values calculated for Ni as shown in Table 4. As baseline 131.2 mg/kg falls in the Emmanuel Arhin http://orcid.org/0000-0002-1724-8307 range estimated by global accepted value in soils (10 mg/kg – 15 mg/kg) but outside the Italian refer- ence value for As in soils (20 mg/kg). Food and most References drinking water are exported so this baseline for As Albanese, S. (2014). Determination of the geochemical back- may not lead to any environmental health problems. ground and baseline in the soils of Campania region: an Adapting this value will result in As-related diseases overview. Ecoremed, Napes,1–25. such as heart diseases (hypertension-related cardio- Alloway, B. J. (Ed.). (2012). Heavy metals in soils: trace vascular diseases) cancer, stroke (cerebrovascular metals and metalloids in soils and their bioavailability (Vol. 22). Springer Science & Business diseases), chronic lower respiratory diseases, and dia- Media. betes Järup (2003), Tchounwou, Yedjou, Patlolla, & Arhin, E., Mouri, H., & Kazapoe, R. (2017). Inherent errors Sutton, 2012). The baseline value calculated for Pb in using continental crustal averages and legislated (6.70 mg/kg) in this study was lower than the average accepted values in the determination of enrichment fac- crustal value of 12.5 mg/kg and much lower than the tors (EFs): A case study in northern ghana in developing Italian reference value for Pb in soils peg at environmental policies. Journal of Geography and Natural Disasters, 7(204), 2167++0587. 100 mg/kg. Bellis, D. J., Satake, K., Noda, M., Nishimura, N., & McLeod, C. W. (2002). Evaluation of the historical records of lead pollution in the annual growth rings and Conclusion bark pockets of a 250-year-old Quercus crispula in Nikko, Background and baseline values have been calculated Japan. Science of the Total Environment, 295(1–3), 91–100. for As, Cr, Pb, Co and Ni. The background values were GEOLOGY, ECOLOGY, AND LANDSCAPES 207 Caballero, B., Trugo, L. C., & Finglas, P. M. (2003). McLennan S.M., & Murray R.W. (1998) Geochemistry of Encyclopedia of Food Sciences and Nutrition. Academic: sediments. In: Geochemistry. Encyclopedia of Earth Elsevier Science B.V., Amsterdam.. Science. Springer, Dordrecht Cicchella, D, De Vivo, B, & Lima, A. (2005). Background Papastergios, G., Fernandez-Turiel, J. L., Filippidis, A., & and baseline concentration values of elements harmful to Gimeno, D. (2011). Determination of geochemical back- human health in the volcanic soils of the metropolitan ground for environmental studies of soils via the use of and provincial areas of napoli (italy). geochemistry: HNO 3 extraction and Q–Q plots. Environmental Earth exploration. Geochemistry: Exploration, Environment, Sciences, 64(3), 743–751. Analysis, 5(1), 29-40. doi:10.1144/1467-7873/03-042 Papastergios, G., Fernandez-Turiel, J. L., Georgakopoulos, A., Cornu, S., Lucas, Y., Lebon, E., Ambrosi, J. P., Luizão, F., & Gimeno, D. (2010). Arsenic background concentrations Rouiller, J., & Neal, C. (1999). Evidence of titanium in surface soils of Kavala area, northern Greece. Water, mobility in soil proﬁles, Manaus, central Amazonia. Air, & Soil Pollution, 209(1–4), 323–331. Geoderma, 91(3–4), 281–295. Parra-Avila, L. A., Bourassa, Y., Miller, J., Perrouty, S., Czarnek, K., Terpiłowska, S., & Siwicki, A. K. (2015). Fiorentini, M. L., & McCuaig, T. C. (2015). Age con- Selected aspects of the action of cobalt ions in the straints of the Wassa and Benso mesothermal gold depos- human body. Central-European Journal of Immunology, its, Ashanti belt, Ghana, West Africa. Journal of African 40(2), 236. Earth Sciences, 112, 524–535. Dzigbodi-Adjimah, K. (1993). Geology and geochemical Perrouty, S., Jessell, M. W., Bourassa, Y., Miller, J., Apau, D., patterns of the Birimian gold deposits, Ghana, West Parra-Avila, L. A., . . . Baratoux, L. (2016). Geological Africa. Journal of geochemical exploration, 47(1–3), setting of the Wassa gold deposit, SW Ghana. Ore 305–320. Geology Reviews, 78, 687–691. Gałuszka, A. (2007). A review of geochemical background Riemann, C., & de Caritat, P. (2005). Distinguishing concepts and an example using data from Poland. between natural and anthropogenic sources for elements Environmental Geology, 52(5), 861–870. in the environment: Regional geochemical surveys versus Ghana Statistical Service. (2002). 2000 population and hous- enrichment factors. Science of the Total Environment, 337 ing census. Accra, 6. (1–3), 91–107. Griﬃs, R. J., Barning, K., Agezo, F. L and Akosah, F. K. Rose, A. W., Hawkes, H. E., & Webb, J. S. (1979). (2000). Gold Deposits of Ghana, pp 10-432. Hastings, D. Geochemistry in mineral exploration (2nd ed.). London: A., 1982. On the tectonics and metallogenesis of West Academic Press. Africa: A model incorporating new geophysical data. Rude, R. K., Singer, F. R., & Gruber, H. E. (2009). Skeletal Geoexploration, 20, pp. 295-327. and hormonal eﬀects of magnesium deﬁciency. Journal of Guevara, Y. Z. C., de Souza, J. J. L. L., & Vieira, G. (2018). the American College of Nutrition, 28(2), 131–141. Reference values of soil quality for the rio doce basin. Rudnick, R. L, & Gao, S. (2003). Composition of the con- Revista Brasileira de Ciencia do Solo, 42–58, e0170231. tinental crust. Treatise on Geochemistry, 3, 659. Järup, L. (2003). Hazards of heavy metal contamination. doi:10.1016/B0-08-043751-6/03016-4 British Medical Bulletin, 68(1), 167–182. Salminen, R., & Tarvainen, T. (1997). The problem of deﬁn- Kabata-Pendias, A. (2010). Trace elements in soils and ing geochemical baselines. A case study of selected ele- plants. Boca Raton, Florida: CRC press. ments and geological materials in Finland. Journal of Karim, Z., Qureshi, B. A., & Mumtaz, M. (2015). Geochemical Exploration, 60(1), 91–98. Geochemical baseline determination and pollution Salonen, V. P, & Korkka-Niemi, K. (2007). Inﬂuence of parent assessment of heavy metals in urban soils of Karachi, sedimentsonthe concentrationofheavy metals inurbanand Pakistan. Ecological Indicators, 48, 358–364. suburban soils in turku, ﬁnland. Applied Geochemistry, 22(5), Kesse, G. O. (1985). The mineral and rock resources of 906-918. doi:10.1016/j.apgeochem.2007.02.003 Ghana. Rotterdam, Netherlands: A. A. Balkema Press. Scheinost, A. C. (2005). Metal oxides. In Encyclopedia of soils in Kobierski, M., & Dabkowska-Naskret, H. (2012). Local the environment (pp. 428–438). Amsterdam: Elsevier background concentration of heavy metals in various Academic Press. soil types formed from glacial till of the Inowroclawska Shrivastava, R., Upreti, R. K., Seth, P. K., & Plain. Journal of Elementology, 17,4. Chaturvedi, U. C. (2002). Eﬀects of chromium on the Lange, B., Ent, A., Baker, A. J. M., Echevarria, G., Mahy, G., immune system. FEMS Immunology & Medical Malaisse, F., & Faucon, M. P. (2017). Copper and cobalt Microbiology, 34(1), 1–7. accumulation in plants: A critical assessment of the current Siah, C. W., Ombiga, J., Adams, L. A., Trinder, D., & state of knowledge. New Phytologist, 213(2), 537–551. Olynyk, J. K. (2006). Normal iron metabolism and the Ma, Y., & Hooda, P. S. (2010). Chromium, nickel and cobalt. pathophysiology of iron overload disorders. Clinical In Trace elements in soils (pp. 461–480), John Wiley and Biochemist Reviews, 27(1), 5. Sons, Ltd. London.. Sinclair,A.J.(1991). A fundamental approach to threshold Markus, J., & McBratney, A. B. (2001). A review of the estimation in exploration geochemistry: probability plots contamination of soil with lead: II. Spatial distribution revisited. Journal of Geochemical Exploration, 41(1-2), 1-22. and risk assessment of soil lead. Environment Taylor, S. R. (1964). Abundance of chemical elements in the International, 27(5), 399–411. continental crust: A new table. Geochimica Et Matschullat, J., Ottenstein, R., & Reimann, C. (2000). Cosmochimica Acta, 28(8), 1273–1285. Geochemical background–Can we calculate it? Tchounwou P.B., Yedjou C.G., Patlolla A.K. & Sutton D.J. Environmental Geology, 39(9), 990–1000. (2012). Heavy Metal Toxicity and the Environment. In: 208 R. KAZAPOE AND E. ARHIN Luch A. (eds) Molecular, Clinical and Environmental Wedepohl,K.H.(1995). The composition of the continental Toxicology. Experientia Supplementum, vol 101. crust. Geochimica Et Cosmochimica Acta, 59(7), 1217–1232. Springer, Basel. Whang, R. (1987). Magnesium deﬁciency: Pathogenesis, Ure, A. M., & Berrow, M. L. (1982). The elemental consti- prevalence, and clinical implications. The American tuents of soil. Environmental Chemistry, 2,94–204. Journal of Medicine, 82(3), 24–29. Webb, J. S., & Howarth, R. J. (1979). Regional geochemical Zhu, Y. G., Williams, P. N., & Meharg, A. A. (2008). mapping. Philosophical Transactions of the Royal Society Exposure to inorganic arsenic from rice: A global health of London. B, Biological Sciences, 288(1026), 81–93. issue? Environmental Pollution, 154(2), 169–171.
Geology Ecology and Landscapes – Taylor & Francis
Published: Jul 3, 2021
Keywords: Geochemistry; Background; Baseline; Environment; Surface soil; Ghana
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