Mean Concentrations Of Heavy Metals Research Articles

Chemical forms of heavy metals in agricultural soils affected by coal mining in the Linhuan subsidence of Huaibei Coalfield, Anhui Province, China.

Total concentrations of heavy metals in soils may not be enough to understand their mobility and bioavailability. It is important to evaluate the degree of association of heavy metals with different chemical forms of soil. The sequential extraction method was applied to evaluate the mobile behavior of Cd, Cr, Cu, Ni, Pb, and Zn in 42 representative soil samples from the Linhuan subsidence of Huaibei Coalfield, Anhui Province, China. The results showed that mean concentrations of heavy metals were higher than background values of Huaibei City surface soil by a factor of 1.16 to 3.21 (Cd, 3.21; Cr, 1.19; Cu, 1.16; Ni, 1.23; Zn, 1.85) except Pb (0.89). Most of the total Cr, Cu, Ni, Pb, and Zn were present in the residual forms (above 70%), while Cd was dominated by the exchangeable forms (42%). The correlations analysis showed that the mobility of Cd, Cu, Pb, and Zn in soil was affected by both physicochemical properties and total metal concentrations. In contrast, the moblity of Cr and Ni of soil was mainly affected by their total metal concentrations. According to assessments by the potential ecological risk index (RI) and the risk assessment code (RAC), Cr, Cu, Ni, Pb, and Zn posed no or low risk. However, Cd presents high to very high risk, due to its higher exchangeable and carbonate-bound fractions.

Bioaccumulation of heavy metals in crop plants grown near Almeda Textile Factory, Adwa, Ethiopia.

The contents of heavy metals cadmium (Cd), cobalt (Co), chromium (Cr), copper (Cu), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) present in water (wastewater and wetland), soils, and food crops collected from the vicinity of Almeda Textile Factory were quantified using Flame Atomic Absorption Spectrometer (FAAS) in order to assess the environmental impact of the textile factory. The contents of heavy metals determined in the wastewater were found below the recommended limit set by WHO and United States Environmental Protection Agency (US EPA) except for Cr, which was found slightly higher than WHO permissible limit. Besides, the contents of the heavy metals determined in soils were below the permissible level of FAO/WHO and Canada maximum allowable limits. Moreover, only the concentrations of Cd and Pb were found above the permissible level set by FAO/WHO in the crop plants studied. Generally, the mean concentrations of heavy metals in the plants were in the decreasing order of: Mn>Zn>Cu>Pb>Ni>Co>Cr>Cd. Nevertheless, higher bioconcentration factor (BCF) was found for Cd (0.108-1.156) followed by Zn (0.081-0.499). In conclusion, comparison of heavy metal concentrations with the permissible limits in all collected sample types i.e. water, soil, and crop plants did not show significant pollution from the factory.

Prevalence of Chromium in Fish Feed and Commercially Cultivated Tilapia

Levels of contaminants in fish are of particular interest because of the potential risk to humans who consume them. The present study was carried out to investigate contamination of heavy metals in commercially cultivated Tilapia fish species available in different kitchen markets of Dhaka city as well as, in the fish feeds and fishes from controlled fish farm. The results showed that the mean concentrations of heavy metal, Cr was higher in liver than muscle. Higher levels of Cr were found in the fish feeds commercially available. Interestingly, there was also significant level of Cr observed in the controlled fish feed and fishes.

Heavy metal pollution assessment in the sediments of lake Chad, Nigerian sector

Sediments were collected from Dumba and KwataYobe of Lake Chad, Nigerian Sector.The aim was to assess the pollution statusof the sediments of the lake. The concentration of heavy metals, Cadmium (Cd), Chromium (Cr), Copper (Cu), Iron (Fe), Manganese (Mn), Nickel (Ni), lead (Pb), Z (Zn) and Arsenic (As) were analysed using energy dispersive x-ray fluorescence (EDXRF). The mean concentration of heavy metals varies between 0.01 to 80877.06 ±10.12mg/kg, were compared with standard average shale to assess the pollution status of the pollution in Dumba and KwataYobe sediments for Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn and As was assessed using geo-accumulation index (Igeo). The results indicated that the sediments have been polluted with Cd, Cr, Fe, Mn, Pb, Zn and As.The Igeo values for Cd, Cr, Cu, Fe, Mn, Ni and Zn at KwataYobevaries between 0.007 to 0.630, indicating unpolluted sediments, while Igeo values for Cd at Dumba and Pb in both sites varies between 1.002 + 01.550 indicating moderately polluted sediments.Igeo values for As varies between 10. 411 to 13.20 in both sites indicating very highly polluted sediments. The Igeo values for Cd at Dumba, Pb and As in both sites indicated that the sediments were polluted. Keywords: Assessment,Average shale, Geo-accumulation index, Heavy metal pollution, Sediments.

Heavy Metals in Epiphytic Lichens and Mosses of Oil–Producing Communities of Eket and Ibeno, Akwa Ibom State – Nigeria

Epiphytic lichen (Parmelia carperata) and moss (Polytrichum juniperinum, Calymperes erosum and Racopilum africanum) samples were used as bioindicators and bioaccumulators of atmospheric heavy metals deposition in oil–producing host communities of Eket and Ibeno Local Government Areas of Akwa Ibom State – Nigeria. Sampling of lichen and moss species that are found to grow extensively and abundantly on the stems and branches of several plants was performed during September 2014 at 25 sampling location sevenly distributed over the two oil–producing host communities studied. Unwashed, oven dried and homogenized powdered lichen and moss samples were mineralized using wet digestion with 3:1 mixture of concentrated nitric acid and perchloric acid in Teflon beakers on a Gerhardt digestion hot plate. The concentrations of heavy metals and/or trace elements were determined by atomic absorption spectrometry (AAS) equipped with flame and/or graphite furnace systems. The concentration of heavy metals in lichen and moss samples ranged from 0.003 – 0.009 μg g−1 for Cadmium (Cd); 0.006 – 7.654 μg g−1 for Chromium (Cr); 1.120 – 1.999 μg g−1 for Cobalt (Co); 8.954 – 116.760 μg g−1 for Copper; 25.980 – 193.260 μg g−1 for Manganese (Mn); 2.268 – 23.783 μg g−1 for Nickel (Ni); 0.034 – 14.880 μg g−1 for Lead (Pb), and 26.230 – 98.780μg g−1 for Zinc (Zn).The mean concentration of heavy metals in the lichen and moss samples can be arranged in the decreasing order as follows: Mn > Zn > Cu > Ni > Cr > Pb > Co > Cd and the statistical analyses revealed that strong correlations exist between Cu–Pb, Cu–Zn, Pb–Ni and Mn–Zn concentrations. Some of the target heavy metals such as Cd, Cr, Mn, Ni and Zn were accumulated at higher concentrations in mosses compared to lichens from the same sampling location. There is some evidence that different site–specific characteristics affect the spatial distributions patterns and temporal trends of atmospheric deposition of heavy metals in the two oil–producing communities of Eket and Ibeno, Akwa Ibom State – Nigeria. However, a comparison with the previous study conducted in 2004by Ite et al. showed a slightly decreasing trend of atmospheric heavy metal deposition and these results confirmed that air quality has not further deteriorated in the two oil–producing communities studied over the last 10 years.

Assessment of heavy metal contamination in raw milk for human consumption

The presence of heavy metals in various farm inputs, including feed, fertilizer, water and environment leads to excretion of the residues in animals’ milk. Because consumption of milk contaminated with heavy metals poses serious threats to consumers’ health, a study was conducted in 2012 – 2013 in Pakistan to evaluate the concentration of heavy metals in unprocessed raw milk procured in different seasons from Jhang city, Punjab, Pakistan. A total of 400 milk samples was collected from milk shops and dairy farms, and the contents of heavy metals, i.e. copper (Cu), lead (Pb), cadmium (Cd) and chromium (Cr) were analysed via atomic absorption spectrometry. Results indicated that the average concentrations of Cu, Pb and Cd were significantly higher than International Dairy Federation Standards. Within a season, heavy metal levels differed significantly among samples. For each type of milk source, there was a significant difference in mean concentration of heavy metals between summer and winter. Based on these findings, there is a critical need to set legal limits and surveillance for heavy metals in an animal’s milk. Keywords: Consumer, health metals, milk, season

Distribution of heavy metals and benthic macroinvertebrates: Impacts from typical inflow river sediments in the Taihu Basin, China

To characterize the distribution of heavy metals and benthic macroinvertebrates and to evaluate the relationship between metal pollution and benthic community structure, we collected samples of typical inflow river sediments from nineteen sites in the Taihu Basin in December 2012 and April and September 2013. The results showed that the mean concentration of heavy metals in the river sediments followed the order of Zn>Cr>Cu>Pb>Ni>As>Cd>Hg, and these metals may present moderate ecological risks. Compared to the background concentrations, it is likely that Cd and Cu pose much higher pollution than the other metals and should receive more attention. In terms of the distribution of the heavy metals, higher concentrations were found at the S1 and S2 sampling sites, while the other sampling sites exhibited relatively lower concentrations because of industrial wastewater containing heavy metals. The structure of the benthic macroinvertebrate community was also investigated, and the correlations between the heavy metals and the benthic communities were analyzed. The mean abundance and biomass of benthic macroinvertebrates in the study area were 49.22–117.23ind./m2 and 42.70–55.70g/m2, respectively, and 4 phyla and 8 classes were represented. The dominant groups were mollusks and arthropods. The FBI, BPI, GI values were low with means of 0.51, 0.41 and 0.16, respectively, and based on the GI and BPI values, most of the sampling sites were clean or slightly polluted with a minimal amount of the study area being moderately polluted. However, the FBI results indicated that all sampling sites were clean, but this may not be consistent with the pattern of pollution in the study area. The results of the correlation relationship analysis between the benthic community metrics and the heavy metal risk indices indicated that the abundance and biomass of Oligochaeta is the most sensitive to heavy metal contamination followed by Hirudinea, Gastropoda, Insecta, and the Goodnight–Whitley index because of significant correlation. And within a certain range, the Goodnight–Whitley index showed an increasing trend when pollution become more serious. However, some metals, such as Eri of Ni, Eri of Cd, Eri of Hg, Eri of Cu, Eri of As, and the RI significantly correlated with the benthic community metrics. Heavy metals in sediments may adversely impact the benthic community, and As and Cu have the greatest effect. Thus, the key influencing environmental factors may be As and Cu, and our results suggest that the benthic community, especially the abundance and biomass of Oligochaeta could be used in biomonitoring for heavy metal ecological risk from the studied area in the Taihu Basin, China.

The Content of Heavy Metal in the Labu Riverbed Sediments: An Assessment of the Level of Pollution Applying Sediment Quality Guidelines and Geoaccumulation Index

River bed sediments from thirteen (13) sampling stations, from Labu River were collected in June and December 2014. The aim is to identify the source and ascertain the current levels of heavy metal pollutions. The selected heavy metals (Cr, Cu, Fe, Ni, Zn, As, Cd and Pb) were analysed by using Inductively Couple Plasma Mass Spectrophotometry (ICPMS). Metals were statistically analysed and compared with Dutch/Malaysia Sediments Quality Guidelines (Target and intervention values) and the Canadian Sediment Quality Guidelines (ISQG and PEL). Geoaccumulation index (Igeo) was calculated and metals were classified. The results showed that the mean value for Cr is 19.74±10.36 mg kg-1, Cu (7.33±2.35 mg kg-1); Fe (7636.39±26.38 mg kg-1); As (11.67±3.59 mg kg-1); Cd (0.097±0.03 mg kg-1) and Pb (26.23±5.33 mg kg-1). The compared sediment guidelines revealed that Cr (51.55 mg kg-1) in SW9, Pb in SW1 (36.43 mg kg-1) and SW13 (37.42 mg kg-1) and As in all of the stations (SW1-SW13) did not meet the Canadian ISQG and were polluted. The geoaccumulation index (Igeo) showed that, Cr (-3.38±0.17), Cu (-3.22±0.12), Ni (-3.37±0.24), Zn (-2.14±0.23), Cd (-3.38±0.17) and Pb (-3.22±0.12) were practically uncontaminated. However, As (2.14±0.13) was classified as moderately contaminated. Based on mean concentrations of heavy metals with the compared Sediments Quality Guidelines (SQG) and Index, it is concluded that As is the heavy metal of concern in the Labu catchment. There is need for the authorities to pay more attentions to sediment pollution problem due to As and address riverbed sediment pollution problems in the different locations as indicated by ISQG due to anthropogenic influences from the KLIA, Dengkil sand mine and Agriculture developments projects in the study area.

Health Risk Assessment of Fe, Mn, Cu, Cr in Drinking Water in some Wells and Springs of Shush and Andimeshk, Khuzestan Province, Southern Iran

Background: In the current study,the hazard quotient, the hazard index (HI) and spatial variations of Fe,Mn,Cu and Cr in drinking water sources of Andimesk-Shush, Khuzestan Province, Southern Iranaquifer were assessed. Methods: We compared theconcentrations of aforementioned heavy metals in wells and springs inAndimeshk and Shush regions. The non-carcinogenic risk assessment of heavy metals was implemented usingUnited States Environmental Protection Agency (USEPA) index.The spatial maps in the area were developed by geostatistical methods. Results: Mean concentrations of heavy metals in groundwater sources of the study area in decreasing order was as follows: Cu >Mn> Fe> Cr. Except for iron,mean heavy metal concentrations were higher than the standard levels. Manganese concentration in 41.5% of the samples exceeded the permissible limits. Copper was higher than the safety limit in 74% of the samples, and chromium in 54% of the cases. The spatial pattern of heavy metals concentrations indicated higher concentrations in the southern parts of the region. The mean hazard quotients of most samples for the four heavy metals were lower than one, indicating that there was no immediate threat due to the exposure to these heavy metals. The calculated accumulated hazards of these heavy metals produced different results, with hazard indices of higher than one. Conclusion: The accumulated hazard indicesfor the evaluated metals were higher than one, indicating that chronic ingestion of these waters threatens the health of local consumers on the long run.

Health Risk Assessment of Heavy Metals in Traditional Cosmetics Sold in Tunisian Local Markets.

This study was undertaken in order to determine heavy metal contents in twelve (n = 12) henna brands and eleven (n = 11) kohl products. An analytical test was performed for Pb, Cd, Cu, and Zn in henna and kohl products using atomic absorption spectrophotometery. The overall mean concentrations of heavy metals in henna varied between 1.2 and 8.9 μg g−1 for Pb; 0.8 and 18.6 μg g−1 for Cd; 0.5 μg g−1 and 3.3 μg g−1 for Cu; and 3.7 μg g−1 and 90.0 μg g−1 for Zn. As for kohl products, Pb concentrations ranged between 51.1 μg g−1 and 4839.5 μg g−1, Cd concentrations ranged between 1.0 μg g−1 and 158.6 μg g−1, Cu concentrations ranged between 2.5 μg g−1 and 162.5 μg g−1, and Zn concentrations ranged between 0.7 μg g−1 and 185.0 μg g−1. The results of our study revealed that Pb, Cd, Cu, and Zn contents in investigated samples were high, making from the prolonged use of such products a potential threat to human health. Therefore, major quality controls are recommended in order to enforce acceptable limits of potential contaminants in cosmetics and good manufacturing practice.

Accumulation and source of heavy metals in sediment of a reservoir near an industrial park of northwest China

The accumulation and source of heavy metals As, Ba, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn in the surface sediment of a reservoir near an industrial park of northwest China were determined by enrichment factor and multi-variate statistical analysis. Multivariate statistical analyses, i.e., factor analysis, cluster analysis, and correlation coefficient analysis, were used to identify the possible sources of the heavy metals. The results show that the mean concentrations of As, Ba, Co, Cr, Cu, Mn, Ni, Pb, V, and Zn in the reservoir sediment are higher than their corresponding concentrations in the control sample, indicating all analyzed heavy metals accumulated in the surface sediments. The values of the mean concentrations of heavy metals in the surface sediment divided by their corresponding concentrations in the control sample increase in the order of Ba = Cr<Co = Pb<V<Ni<Cu = Zn<As<Mn. The enrichment factor values of Ba and Cr in the surface sediment samples are<2, revealing minimal enrichment, while the enrichment factor values of As, Co, Cu, Mn, Ni, Pb, V, and Zn are in the range of 2‒5, displaying moderate enrichment. Combining the results of correlation coefficient analysis, factor analysis, and cluster analysis, three main sources of these heavy metals were identified. As, Co, Cu, Mn, Ni, and V have mixed sources of natural and industrial sources and local consumption residues; Pb and Zn mainly originate from industrial activities, while Ba and Cr primarily originate from natural sources.

Pollutants and parasites in bycatch teleosts from south eastern Spanish Mediterranean's fisheries: Concerns relating the foodstuff harnessing

This research provides an evaluation of the quality and health status of some locally abundant fish species, usually otter-trawl bycatch species. The study was conducted in the southern and eastern Spanish Mediterranean coast. Mean concentration of heavy metals in muscle and parasitisation indices showed moderate levels. Higher lead concentration was found in fish from the western Alboran and arsenic, cadmium and mercury were more present on fishes from the eastern Alboran area, although most species analysed contain moderate levels of heavy metals in muscle. Concerning parasitisation, F. Anisakidae nematodes were present in all the species, except sardine. Only mercury showed a positive relationship with parasitisation.We also considered three feeding guilds. Metal mean concentrations were higher in benthivores and more littoral fishes. Pelagic planktivores species are the healthiest and the more suitable for consumers from the sanitary point of view.

Assessment of the Heavy Metals in Al Asfar Lake, Al‐Hassa, Saudi Arabia

ABSTRACT: Al Asfar Lake is a shallow wetland and habitat for wildlife and birds in a desert environment. The water of this lake is originated from the drainage water collected by earthen drainage network and discharged into the lake. The purpose of this study was to assess physico‐ chemical characteristics and some of heavy metals in Al Asfar lake water. The studied parameters are iron, manganese, copper, zinc, cadmium, chromium, lead, pH, electrical conductivity, and nitrate. Forty‐five surface water samples were collected in March 2013. The results revealed that the pH ranged from 7.33 to 8.67, electrical conductivity ranged from 8.28 to 11.34 dS/m, and NO3− ranged from 0.84 to 2.29 mg/L. In addition, heavy metals concentrations in water were found in the following order: Fe &gt; Mn &gt; Cu &gt; Zn &gt; Cd &gt; Cr = Pb. The mean concentrations of heavy metals in surface water of Al Asfar lake ranged from 0.027 to 0.159 ppm, 0.007 to 0.142 ppm, 0.005 to 0.017 ppm, 0.005 to 0.066 ppm, 0.001 to 0.033 ppm, 0 ppm, and 0 ppm for iron, manganese, copper, zinc, cadmium, chromium, and lead, respectively. Moreover, pH, NO3−, Fe, Mn, and Zn concentrations in the surface water of Al Asfar Lake were found to be within the international permissible limits. On the other hand, Cu and Cd concentrations exceeded the international permissible limits. The high level of some parameters of the measured heavy metals could be attributed to the contamination of Al Asfar Lake with discharge water enriched with chemical fertilizers in addition to domestic and industrial effluents.

Assessment of the Heavy Metals in Al Asfar Lake, Al-Hassa, Saudi Arabia.

Al Asfar Lake is a shallow wetland and habitat for wildlife and birds in a desert environment. The water of this lake is originated from the drainage water collected by earthen drainage network and discharged into the lake. The purpose of this study was to assess physico- chemical characteristics and some of heavy metals in Al Asfar lake water. The studied parameters are iron, manganese, copper, zinc, cadmium, chromium, lead, pH, electrical conductivity, and nitrate. Forty-five surface water samples were collected in March 2013. The results revealed that the pH ranged from 7.33 to 8.67, electrical conductivity ranged from 8.28 to 11.34 dS/m, and NO(3)(-) ranged from 0.84 to 2.29 mg/L. In addition, heavy metals concentrations in water were found in the following order: Fe > Mn > Cu > Zn > Cd > Cr = Pb. The mean concentrations of heavy metals in surface water of Al Asfar lake ranged from 0.027 to 0.159 ppm, 0.007 to 0.142 ppm, 0.005 to 0.017 ppm, 0.005 to 0.066 ppm, 0.001 to 0.033 ppm, 0 ppm, and 0 ppm for iron, manganese, copper, zinc, cadmium, chromium, and lead, respectively. Moreover, pH, NO(3)(-), Fe, Mn, and Zn concentrations in the surface water of Al Asfar Lake were found to be within the international permissible limits. On the other hand, Cu and Cd concentrations exceeded the international permissible limits. The high level of some parameters of the measured heavy metals could be attributed to the contamination of Al Asfar Lake with discharge water enriched with chemical fertilizers in addition to domestic and industrial effluents.

Heavy Metal Assessment in Sediment Samples Collected From Pattipulam to Dhevanampattinam along the East Coast of Tamil Nadu Using EDXRF Technique.

Selected heavy metals (Mg, Al, K, Ca, Ti, Fe, V, Cr, Mn, Co, Ni, Zn, As, Cd, Ba, La and Pb) in the coastal sediment samples from the Pattipulam to Dhevanampattinam along the East Coast of Tamil Nadu, India has been determined to assess the contamination and metal enrichment status. The metal concentration were analysed in sediment samples using Energy dispersive X-ray flurascence technique. The mean concentration found to be : 1665 mg kg-1 for Mg; 21719 mg kg-1 for Al; 8405 mg kg-1 for K; 9284 mg kg-1 for Ca; 1520 mg kg-1 for Ti; 6554 mg kg-1 for Fe; 35.3 mg kg-1 for V; 30.1 mg kg-1 for Cr; 130.4 mg kg-1 for Mn; 2.4 mg kg-1 for Co; 20.2 mg kg-1 for Ni; 62.2 mg kg-1 for Zn, 6.2 mg kg-1 for As, 3.4 mg kg-1 for Cd; 404.9 mg kg-1 for Ba; 15.1 mg kg-1 for La; 12.1 mg kg-1 for Pb; The determined mean metal concentration is in the order of Al > Ca > K > Fe > Mg > Ti > Ba > Mn > Zn > V > Cr > Ni > La > Pb > As > Cd > Co. A mean concentrations of heavy metals found in sediments are significantly lower than those from the background values. The heavy metals pollution assessments of sediments are determined by using pollution indices like contamination factor (CF), pollution load index (PLI) and potential contamination index (Cp). The sequence of the contamination factors of studied metals is Cd > Ba > Zn > Pb > As > Ca > Ti > Cr > K > Ni > Al > V > La > Mn > Fe > Co > Mg. This study reflects these pollution indices are sufficient to assess the pollution status of sediments.

Assessment of Heavy Metal Pollution And Potential Ecological Risk of Sediments of East Coast of Tamilnadu by Energy Dispersive X-Ray Fluorescence Spectroscopy (EDXRF) and Sediment Quality Guidelines (SQGS)

The heavy metals inventory and the ecological risk of the coastal sediments from Periyakalapattu to Parangipettai coast along the Bay of Bengal coastline, Tamilnadu, India were investigated. The concentration of heavy metals like Mg, Al, Si, K, Ca, Ti, Fe, V, Cr, Mn, Co, Ni, Cu, Zn, As, Cd, Ba, La and Pb were determined in sediment using energy dispersive X-ray fluorescence (EDXRF) technique. The mean concentration of heavy metal found in the order of Mn> Ba > V > Cr > Zn > La > Ni > Si >Pb> Co > As > Cd > Cu > Al > Fe >Ca> Ti > K > Mg. The assessment of heavy metal enrichment as well as the contamination status in the sediments was determined by the pollution load index. Further the potential ecological risk of heavy metals in sediments studied by different sediment quality guidelines (SQGs).

Assessment of the Contribution of Road Runoffs to Surface Water Pollution in the New Juaben Municipality, Ghana

Road runoffs were sampled from five highways and five urban roads located in the New Juaben Municipality during the late storm events in the month of November 2014 and the early storm events in January 2015. A variety of water quality parameters such as, pH, temperature, turbidity, electrical conductivity (EC), total suspended solids (TSS), total dissolved solids (TDS), aqueous concentrations of Chloride (Cl-), Phosphate (), Nitrate () and Sulphate () ions as well as the total concentrations of some selected heavy metals (Fe, Cu, Zn, Pb, Cd, Ni and Cr) were analysed for both periods. Although the results for the studied parameters, particularly the heavy metals varied for both sampling periods, the general trend indicated an increase in accumulation from November 2014 to January 2015. This was attributed to vehicular deposition as well as other natural and anthropogenic depositions on the road surfaces during the antecedent dry weather period between the two sampling months. The highest increase in pollutant loadings was associated with the heavy metals and some physico-chemical parameters such as TSS, TDS, EC and turbidity. Generally, EC, TDS, TSS and turbidity were above the permissible limits of the Environmental Protection Agency (EPA) of Ghana for both sampling periods. However, almost all the mean concentrations of heavy metals recorded for both road runoffs and the control samples were within the permissible limits of the Ghana EPA with some few exceptions.

Heavy Metal Contamination in Rice-Producing Soils of Hunan Province, China and Potential Health Risks.

We studied Cd, Cr, As, Ni, Mn, Pb, and Hg in three agricultural areas of Hunan province and determined the potential non-carcinogenic and carcinogenic risks for residents. Soil and brown rice samples from Shimen, Fenghuang, and Xiangtan counties were analyzed by atomic absorption spectroscopy. Soil levels of Cd and Hg were greatest, followed by As and Ni. The mean concentrations of heavy metals in brown rice were Cd 0.325, Cr 0.109, As 0.344, Ni 0.610, Mn 9.03, Pb 0.023, and Hg 0.071 mg/kg, respectively. Cd and Hg had greater transfer ability from soil to rice than the other elements. Daily intake of heavy metals through brown rice consumption were estimated to be Cd 2.30, Cr 0.775, As 2.45, Ni 4.32, Pb 0.162, Mn 64.6 and Hg 0.503 µg/(kg·day), respectively. Cd, Hg and As Hazard Quotient values were greater than 1 and Cd, Cr, As and Ni Cancer Risk values were all greater than 10−4. The total non-carcinogenic risk factor was 14.6 and the total carcinogenic risk factor was 0.0423. Long-term exposure to heavy metals through brown rice consumption poses both potential non-carcinogenic and carcinogenic health risks to the local residents.

Evaluation Of The Usefulness Of Spider Webs As An Air Quality Monitoring Tool For Heavy Metals

Abstract The study aims at evaluating whether webs reflect the level of air pollution measured with conventional methods. Webs of species Malthonica silvestris (l. KOCH, 1872) (Araneae: Agelenidae) were sampled. Samples were analyzed for heavy metals (Pb, Zn) content. According webs analyses and classic measurements three traffic-oriented sites in Wroclaw (South-West Poland) showed significantly higher mean concentrations of heavy metals than two other sites situated in quieter, low traffic areas. A very strong significant positive correlation was revealed among average concentrations of Zn and Pb associated with fine particulate matter of atmospheric aerosol (PM1) and webs. We also observed a very strong significant positive correlation among Zn and Pb concentrations on webs and PM2.5. Any significant correlation among PM-emission fractions 2.5 and 10 and associated heavy metals and dust deposited on spider webs was not observed. Although spider webs proved useful indicators of environmental pollution the obtained results suggest that this tool should be used to evaluate the emission of heavy metals in the similar way as other bioindicators such as mosses and lichens are commonly used. The measured concentrations on webs do not reflect results obtained with classic methods. We conclude that spider webs are good for bioindication of road traffic emissions, they could be even more reliable compared to use of some other bioindicators whose activity is often limited by the lack of water and sun.

Concentrations, hydrochemistry and risk evaluation of selected heavy metals along the Jimi River and its tributaries at Obuasi a mining enclave in Ghana

Surface water represents significant source of fresh water for irrigation and drinking purposes and therefore preserving the availability and quality of this resource is extremely important. Surface water samples within the catchment area of the Obuasi mine were analysed to assess dissolved concentrations, hydrochemistry, risk evaluation of selected metals and their effects on drinking water quality. Water samples were collected from the Jimi River and its tributaries and analysed for physico-chemical parameters and heavy metals using standard analytical methods. Health risk assessment of As, Pb, Fe, Cd, Ni and Zn based on the average daily dose, hazard quotient and cancer risk was also determined. The results indicated that, most of the physico-chemical parameters are within WHO guidelines except conductivity, turbidity, alkalinity and total hardness. The mean concentrations of heavy metals and ionic dominance pattern follow the order: Cd Mg2+ > K+ > Na+ and HCO3 − > SO4 2+ > Cl−. The health-risk assessment revealed that hazard quotient (HQing) and hazard index (HIing) values were below the acceptable limit, indicating non-carcinogenic risk to the recipient via oral intake and dermal contact of the water. The calculated values for chronical daily intake (CDI) were found in the order of Fe > Zn > As > Pb > Cd > Ni in both adults and children. The carcinogenic risk (CRing) via ingestion route for As, Cd, and Pb were higher than the acceptable limit (10−6). Multivariate statistical analysis results revealed that natural processes and anthropogenic activities were the main sources of water contamination. The results suggested multiple natural processes and anthropogenic activities like mining significantly contribute to the considerable environmental pollution contamination of the Jimi River and its tributaries. Our findings have important public health implications, and we suggest that a system of sentinel surveillance is being implemented that, in turn, can guide adequate responses.