Average Metal Concentrations Research Articles

Heavy metal contamination in marine fish from the Andaman sea: Influence of habitat and health risk assessment

This study investigates Hg, Cd, Cu, Zn, and Pb concentrations in 324 fish samples from 43 species, including two cephalopod species, in the Andaman Sea. The fish were categorized into pelagic and demersal groups. The findings revealed average heavy metal concentrations in the order: Zn > Cu > Hg > Pb > Cd, with pelagic fish showing higher levels than demersal fish. Certain larger pelagic fish had mercury concentrations above prescribed limits, posing possible health hazards, even though they are less commonly consumed by humans. Cd and Pb levels in certain species exceeded regulatory thresholds of 0.05–1 μg/g and 0.3 μg/g, respectively, while Cu and Zn remained within safe limits. Although the overall cancer risk was low, the Target Hazard Quotient (THQ) and Hazard Index (HI) values surpassed 1, indicating significant health risks from consuming species such as Alopias superciliosus, Isurus oxyrinchus, Lepturacanthus savala, Makaira mazara, and Sphyraena barracuda. These findings underscore the need for ongoing monitoring and public advisories to mitigate health risks.

СОДЕРЖАНИЕ ТЯЖЕЛЫХ МЕТАЛЛОВ В МЫШЦАХ ЛЕЩА ИЗ РАЗНЫХ ПЛЕСОВ РЫБИНСКОГО ВОДОХРАНИЛИЩА

The purpose of the study is to determine the concentration of heavy metals (Cd, Pb, Al, Cr, Cu, Mn, Fe, Co, Ni, V) in the muscle tissue of bream from the Sheksna and Volga reaches – areas of the Rybinsk reservoir, which differ in the level of anthropogenic impact. Tasks – to reveal the intensity of accumulation of heavy metals in the muscles of bream from these stretches; evaluate the safety of meat for human consumption. The object of the study were sexually mature, approximately the same size individuals of bream caught by trawl during the feeding period (n = 40). Fish were dissected muscle tissue and frozen until analysis. In the laboratory, the fabric was dried at 60 °C to constant weight, and the content of heavy metals was determined using an OES ICP Optima 2000 DV (Perkin-Elmer, USA). It was found that Al, Fe, and Co accumulated more intensively in the muscles of the bream from the Sheksna reach, which was subjected to a greater anthropogenic load. The relationship between the accumulation of toxicants in the body of fish and their negative impact on the physiological and biochemical parameters of bream has been confirmed. The synchronism of Fe bioaccumulation depending on their concentration in bottom sediments was revealed. The following average concentrations of heavy metals in the muscles of bream from the Rybinsk reservoir were obtained: Cd – 0.005 mg/kg; Pb – 0.048; Al – 10.414; Cr – 0.149; Cu – 0.978; Mn – 0.631; Fe – 8.692; Co – 0.006 mg/kg. The content of Ni and V turned out to be below the detection limit. The results obtained meet the requirements of domestic and international standards, therefore, bream muscles are safe for human health and can be eaten.

Tracing Heavy Metal Dynamics in Mangrove Sediments: A Study from Ujung Kulon National Park

The dynamics of heavy metal concentrations in the sediments of mangroves are crucial for understanding the health and sustainability of these ecosystems. This study, conducted in a conservation area of Ujung Kulon National Park (UKNP) in Indonesia, investigated the distribution of heavy metals in mangrove sediments, which are vital in trapping these potentially harmful substances due to their absorption, sedimentation, and bioaccumulation capabilities. By analyzing sediment cores from different intertidal zones (interior, fringe, and mudflat) through Inductively Coupled Plasma - Optical Emission Spectrometry (ICP-OES), this study examined concentrations and distribution patterns of six heavy metals: manganese (Mn), copper (Cu), zinc (Zn), cobalt (Co), chromium (Cr), and Iron (Fe). The results indicated that the average concentration of heavy metals followed a decreasing order of Fe> Mn > Zn > Cu > Cr> Co across all locations. All of the heavy metals in the interior and fringe increased gradually from the year 1900 to the present; on the contrary, the mudflat decreased over the same period. Enrichment Factor (EF) and Geo Accumulation Index (Igeo) were used to evaluate heavy metal pollution levels comprehensively. The study revealed temporal trends in heavy metal concentrations, highlighting the need for further research to mitigate these contaminant's effects on mangrove ecosystems. By integrating the EF, the Igeo index, and quality standards, the research demonstrates that UKNP is likely pristine. Furthermore, this work emphasizes the need to utilize dated environmental archives to reconstruct historical patterns in trace metal pollution in locations where long-term environmental studies remain particularly limited

Enrichment Characteristics, Risk Evaluation, and Source Apportionment of Heavy Metals in Wabu Lake of Yangtze River to Huaihe River Water Diversion Project

Wabu Lake serves as a crucial junction within the Yangtze River to Huai River Water Diversion Project （Yangtze-Chao Lake-Wabu Lake-Huai River）, where clarifying the status and risk levels of heavy metal contamination in the lake is crucial for the aquatic ecological safety along the route of the project. Surface water and sediment samples from 24 locations in Wabu Lake were collected and analyzed for the contents of heavy metals （As, Zn, Pb, Ni, Cu, Cr, Fe, and Cd）. Risk evaluation and source apportionment of heavy metals in the lake were conducted using the human risk assessment （HRA） model, sediment quality guidelines （SQGs）, and positive matrix factorization （PMF） method. The results showed that the average concentrations of heavy metals （except for Cd and Pb） in the surface water were lower than the class III limits of the surface water quality standard （GB 3838-2002）. The average concentration of heavy metals （As, Zn, Pb, Ni, Cu, Cr, Fe, and Cd） in interstitial water were lower than the Criteria Continuous Concentration （CCC） of the National Recommended Water Quality Criteria. The average contents of As, Zn, Pb, Ni, Cu, Cr, and Cd in the sediment exceeded the background values by factors of 1.78, 1.85, 1.42, 1.77, 1.41, 1.38, and 3.46, respectively. In addition, the heavy metals Pb, Cd, and Cr in the Wabu Lake water posed severe risks to human health, with the cancer risk （CR） value for Cr reaching 6.14×10-5. The sediment quality guidelines （SQGs） indicated that the probability of adverse effects on lakes by As, Ni, and Cr was relatively high. The spatial distribution of risk areas showed that the risk control zones for As, Cr, and Ni in Wabu Lake covered almost the entire lake area. The PMF analysis indicated that the primary sources of heavy metals in Wabu Lake were exogenous inputs from industrial, agricultural, and residential activities in surrounding areas, followed by endogenous pollution caused by enclosed aquaculture. The subsequent focus should be on the pollution of heavy metals Cr, Cd, and Pb in the overlying water of Wabu Lake as well as the sediment ecological safety of As, Cr, and Ni in the sediment.

Мікроелементний склад питної води при централізованому водопостачанні промислових міст Дніпропетровської області

The purpose. Ecological and hygienic assessment of the quality of drinking water at the centralized water supply of industrial cities of the Dnipropetrovsk region by the content of trace elements from the group of heavy metals. Object and research methods. The analysis of the content of trace elements from the group of heavy metals in the drinking water of industrial cities of the Dnipropetrovsk region - Dnipro, Kryvyi Rih, Kamianske over a 5-year period was carried out. The evaluation of the obtained data was carried out in accordance with the requirements of the current legislation on the safety and quality of drinking water in accordance with SSRN 2.2.4-171-10, international recommendations and data from the scientific literature. Results. It has been established that in the Dnipropetrovs'k region over the 5-year study period, the percentage of non-standard drinking water samples for sanitary and chemical parameters ranged from 24.4-30.6% from centralized water supply systems, and 14.5-18.4% from water supply networks. The average long-term concentrations of metals in the drinking water of the studied cities ranged from 0.0001 mg/l for mercury to 0.19 mg/l for aluminum, which meets the MAC requirements, but the maximum values of the content of individual metals in all industrial cities exceeded the hygienic regulations, most pronounced for iron, which reached 60%. At the same time, the proportion of samples exceeding the hygienic standard in some years of the study was 5-12%. In the dynamics of the study, a gradual decrease of 14.2-54.5% in the concentration of lead in drinking water in all industrial and control cities was noted (p<0.05; R2= 0.51-0.78). A similar trend is also characteristic of the aluminum content in drinking water in Kryvyi Rih - a 2.5-fold decrease (p<0.001; R2=0.79) during the study period. At the same time, a significant increase in the content of a number of trace elements from the group of biotic and abiotic heavy metals was found in Kamianske, in particular copper and zinc - by 2.0-2.4 times (p<0.01; R2= 0.72-0.77), mercury and arsenic - by 1.3-1.9 times (p<0.01; R2= 0.87-0.92). The dynamics of concentrations of other heavy metals in the drinking water of the studied cities was unreliable. The sum of the ratio of the concentrations of trace elements from the group of heavy metals belonging to hazard classes I and II according to the sanitary and toxicological limiting sign of harmfulness ranges from 1.1 to 1.9, i.e. the simultaneous presence of these metals in the drinking water of industrial cities exceeds the safe level regulated by SSRN 2.2.4-171-10. Conclusions. The results of the conducted research indicate the urgency of the problem of ensuring the quality and safety of drinking water intended for human consumption and the need for further improvement of water treatment and control methods at all levels. Keywords. Trace elements, heavy metals, drinking water, content, pollution, impact, public health.

Status of Trace Metals Contamination and Ecological Risk Assessment in Intertidal Sediments Along the Gulf of Guinea

Surface sediments from the intertidal area of Côte d’Ivoire were sampled to investigate trace metals (Hg, Cd, Cr, Cu, Pb, Zn, and As) concentrations to illustrate their spatial distribution and ecological risk of pollution. The average total organic carbon content was 2.04 ± 0.01%. Except for Cr and Zn, the spatial distribution exhibited a similar pattern for TOC, Hg, Cd, Cu, Pb, and As. The average concentrations of trace metals were less than their corresponding upper continental crust (UCC) values, except for Cd and Cr. The pollution indices indicated that sediment quality in the studied area has been impacted by Cd and the Assinie and Bleron sites were the most contaminated. A few ecological risks were posed by Hg, Cd, Cr, and Cu, based on sediment quality guidelines (SQGs). The Pearson correlation showed a significant (p < 0.05) correlation between As, Cd, Pb, Cr, and Hg, suggesting a common origin in sediments. The principal component analysis (PCA) identified As, Cr, Pb, Zn, and Hg might originate from natural source, Cd and Cu might be from natural and anthrogenic sources. Although this study presents the current status of littoral trace metals contamination level in sediments, further studies should integrate the statistical multivariate approach to determine the anthropogenic sources of the trace metals in the intertidal area of Côte d’Ivoire.

Heavy metals concentration and health risk assessment in peanut and date palm from Jigjiga City Markets, Ethiopia

Heavy metals in food can pose significant health risks, necessitating regular monitoring and assessment of their concentrations in commonly consumed foods. This study aims to assess the levels of essential and heavy metals and conduct health risk assessments in peanuts and date palms. Using wet acid digestion, the concentrations of heavy metals: iron (Fe), zinc (Zn), copper (Cu), arsenic (As), lead (Pb), and chromium (Cr) were measured in six each sample of peanuts and date palms, via Flame Atomic Absorption Spectroscopy (FAAS). To assess the health risks for adult males and females, the study calculated the estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI), and incremental lifetime cancer risk (ILCR) based on Maximum Recommended Daily Intake (MRDI) of each metal. The average concentrations of heavy metals in peanuts were: Fe 12.6 ± 0.54, Zn 5.3 ± 0.1, Cu 3.53 ± 0.33, As 0.001 ± 0.0, Pb 0.01 ± 0.0, and Cr 0.02 ± 0.0 in mg/kg. For date palms, the average concentrations were: Fe 40.23 ± 2.5, Zn 48.31 ± 0.8, Cu 10.65 ± 0.05, As 0.05 ± 0.002, Pb 0.2 ± 0.01, and Cr 0.5 ± 0.03 in mg/kg. All measured concentrations were below WHO standards. The estimated daily intake of metals from both food was found to be below the Maximum Recommended Daily Intake (MRDI). The hazard index for peanuts was within safe limits, indicating no significant non-carcinogenic health risks. In contrast, the hazard index for date palms exceeded 1, suggesting potential non-carcinogenic health risks. Incremental lifetime cancer risks were within allowable limits. In conclusion, the concentrations of heavy metals in peanuts and date palms from the Jigjiga market are within safe limits set by the WHO.

Measurements of Heavy Elements and Radioactivity Concentration Levels in Types of Fertilizers and Pesticides Commonly Used in Sana’a Yemen

This study aims to measure heavy metals (HMs) concentration and radioactivity concentration levels in fertilizer and pesticide samples collected from local markets in Sana’a, Yemen. Gamma spectroscopy employing a Survey Sodium Iodide NaI (TI) RIIDEYM-G detector was used for radiation and dose assessments. As for heavy metal analyses, this study used Inductively Coupled Optical Emission Spectroscopy (ICP-OES). Thirty samples were collected from local markets in Sana’a, Yemen. Radioactivity measurements show low levels of radioactivity concentration. The average dose rates due to fertilizer and pesticide samples were 1.14 and 1.07 mSv/y, respectively. These values are nearly equal to the recommended annual radiation dose rate limit (1mSv/y) recommended by the International Commission on Radiological Protection (ICRP). For heavy metal analysis, it was found that the average concentrations of heavy metals (HMs) (cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), and zinc (Zn)) in the fertilizer samples were 1.08 mg/kg, 4.944 mg/kg, 13.8495 mg/kg, 274.371 mg/kg, 3.30446 mg/kg, 15.35686 mg/kg, and 24.4547 mg/kg, respectively. Heavy metal concentrations in fertilizer samples were mainly less than European (EU) guideline limits, with the exception of a few samples. The average concentrations of heavy metals (Cd, Cr, Cu, Fe, Ni, Pb, and Zn) in the pesticide samples were 0.8 mg/kg, 0.5784 mg/kg, 52.280 mg/kg, 73.4651 mg/kg, 2.4482 mg/kg, 3.199 mg/kg, and 1.1309 mg/kg, respectively. The heavy metal concentrations in pesticide samples were less than the corresponding values in fertilizer samples.

Assessment of Metal Pollution in Sediments and Their Bioaccumulation in Phragmites australis from Shoor River, Iran

ABSTRACT Heavy metal contamination is a serious global issue that threatens both environmental and human health. This study investigated the levels of 12 heavy metals in sediments, roots, stems, and leaves of Phragmites australis (common reed) from a river in Iran, using an inductively coupled plasma optical emission spectrometer (ICP-OES). The sediment metal concentration order was: Aluminum (Al) > Iron (Fe) > Manganese (Mn) > Zinc (Zn) > Magnesium (Mg) > Nickel (Ni) > Chromium (Cr) > Lead (Pb) > Copper (Cu) > Arsenic (As) > Vanadium (V) with Cadmium (Cd) below detection limit. Concentrations of As, Ni, Pb, and Zn in the sediments exceeded background values. According to sediment quality guidelines (SQGs), metal concentrations were between the threshold effect level (TEL) and the probable effect level (PEL), remaining below the severe effect level (SEL), except for Ni. Average metal concentrations in plant tissues were lower than in sediment samples, with roots showing higher levels of Cd, V, Cu, Pb, Zn, As, Al, Mg, and Fe than in the shoots, while leaves had higher Ni, Cr, and Mn. The bioaccumulation factor of less than 1 (except for V) indicates limited bioavailibility of these metals.

Determination of heavy metals and health risk assessment in drinking water in Bukayriyah City, Saudi Arabia

Abstract Heavy metal levels, including arsenic, lead, cadmium, mercury, chromium, and nickel, were analyzed in 124 samples of tap and filtered water obtained from Bukayriyah city, Saudi Arabia, using inductively coupled plasma mass spectrometry. Additionally, measurements of total dissolved solids, conductivity, and pH were also performed. The study also evaluated the potential non-cancer and cancer risks (CRs) associated with the ingestion of these heavy metals for both children and adults. The results indicated that the average concentrations of heavy metals in both tap and filtered water were found to be below the recommended limits set by the World Health Organization and the Gulf Standard Organization. To assess the non-carcinogenic risks, the chronic daily intake (CDI), hazard quotient (HQ), and hazard index were calculated for analyzed metals present in both tap and filtered water. In both the children and adult populations, the CDI indices for heavy metals in tap and filtered water followed the order of Cr &gt; Hg &gt; Ni &gt; Pb &gt; As &gt; Cd. However, it is worth noting that the CDI values for tap water were higher than those for filtered water for both children and adults. The descending order of HQ values is as follows: Hg &gt; Cr &gt; As &gt; Cd &gt; Pb &gt; Ni. This indicates that the HQ values for all metals are below the acceptable limit of 1. These findings confirm that the exposure to the examined metals from both tap and filtered water in Bukayriyah City is within safe limits and poses no non-carcinogenic risks. To assess the carcinogenic risks, the incremental lifetime cancer risk (ILCR) and total carcinogenic risk (TCR) were calculated. The order of ILCR values for both children and adults in tap and filtered water is as follows: Ni &gt; Cr &gt; Cd &gt; As &gt; Pb. All ILCR values were below the acceptable limit of 10−6 to 10−4. However, TCR values exceeded this threshold range only for children exposed to tap water, with a value of 1.43 × 10−4. Thus, children exposed to tap water have a potential risk of developing carcinogenic diseases.

Evaluation of selected minerals and health risk and proximate analysis of wasawasa (a street food)

This study was carried out to determine the proximate composition and the potential heavy metal health risk that may be associated with the consumption of wasawasa, a dish made from locally milled yam peels, by examining the presence of six metals (iron, nickel, chromium, sodium, and magnesium and potassium) in samples procured. Sixteen (16) samples of ready-to-eat wasawasa were collected from Aboabo, Manhyia, Sawaba, Asawase, Adenyase, and Ayigya in Kumasi, since these are the communities where wasawasa is mainly produced, sold, and consumed. The samples were digested with a nitric, perchloric, and sulfuric acid mixture and analyzed using a microwave plasma atomic emission spectrometer (Agilent 4210 MP-AES). The average concentrations of metals were Na (8506.88 mg/kg), Mg (222.63 mg/kg), Fe (84.45 mg/kg), Cr (2.31 mg/kg), K (1702.08 mg/kg, and Ni (1.12 mg/kg). Proximate analysis was used to determine Protein, fat, ash, moisture, and fiber content of the local wasawasa, which were found to be 15.667 %, 0.45 %, 1.00 %, 27.54 %, and 0.41 %, respectively. The hazard index of the heavy metals (Fe, Ni and Cr) for both adults and children were each greater than one, indicating the population is likely to experience non-carcinogenic effects from the consumption of wasawasa.

Pollution Profile of the Panvel Creek, Raigad, Maharashtra, India: Analysis of the Heavy Metal Contamination

The concentration of heavy metal levels (Cd, Cu, Hg, Ni, Pb, and Zn) were assessed in water samples from Panvel creek, District Raigad, Maharashtra, West Coast of India. The heavy metals were analysed by using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES). Results of the study reveal that, Cu, Ni, Zn, and Hg were detected in water samples of Panvel creek whereas Pb and Cd were not reported. Levels of Cu range from not detectable to 0.037 ppm whereas concentration of Ni varies from not detectable to 0.048. Zn is the only metal which is consistently detected at both the sites during all seasons whereas its values were moderately high (0.108 ppm) during the monsoon at both sites. Highest values were recorded for Hg, especially during the pre-monsoon. Highest levels of Ni and Zn were detected at both sites during monsoon season whereas Cu, Pb, Hg and Cd were not detected during monsoon at all sites. Further, Cu and Zn were detected during post-monsoon, while other metals such as Ni, Pb, Hg and Cd remain not detectable. Zn was only heavy metal detected at both sites during all sampling seasons while Pb and Cd were absent from the water samples during all the seasons at all sites. Average concentration of heavy metals reported in Panvel creek was found to be in the order of Hg&gt;Zn&gt;Ni&gt;Cu&gt;Pb&gt;Cd. Therefore, the coastal water from the Panvel creek is polluted by heavy metals. Absence of heavy metals like Pb and Cd is attributed to the waste discharged in the creek are free from these metals and is also beneficial to the coastal biota of the creek. Consistent occurrence of Cu, Ni, Zn, and Hg in Panvel creek should not be ignored considering their impact on the ecosystem and marine biota.

Mud matters: exploring the quality and composition of Estonia's curative mud deposits

The study focuses on the current state of curative mud deposits in Estonia as of 2022, examining changes over the past decade and providing essential information on curative mud quality. Total of 64 curative mud samples were collected in 2022, marking the first investigation into hazardous substances such as phenols, petroleum products, and pesticides. The study encompassed analyses of organic and mineral matter content, grain size, microbiology, and heavy metal concentrations, totalling 1649 measurements. Comparisons with previous data revealed stable organic matter concentrations in lake and marine sediments over the last decade. Microbiological contamination in curative mud samples was relatively low, indicating cleanliness. Petroleum product concentrations varied, with Haapsalu at 42 mg/kg, Värska at 118.6 mg/kg, and Käina below the limit of quantification. Phenol concentrations were generally below the limit of quantification, except for Värska. Pesticides were found in Värska samples, but in other sediments, levels were below the limit of quantification. Average heavy metal concentrations in curative mud decreased between 2013–2014 and 2022, remaining below the target value. The study's results are crucial for curative mud-related entrepreneurship in Estonia, facilitating compliance with the new regulatory standards. The comprehensive data obtained will contribute to the consistency and efficacy of curative mud-related practices in the country.

Investigating the Level of Metal’s Toxicity in Used Cell Phone Batteries by TCLP and WET Methods

Introduction: Batteries are widely used in all kinds of electrical and electronic equipment. These batteries contain several metals that lead to the leakage of metals into the soil and underground water in the burial places, which pose serious risks to human health and the environment. Materials and Methods: In this study, the concentration of 15 metals (Ag, Al, As, Ba, Cd, Co, Cs, Cu, Fe, Li, Mn, Pb, Sr, Zn, Ni) in different components of 7 used battery models was investigated using Waste Extraction Test (WET) and Toxicity Characteristic Leaching Procedure (TCLP) toxicity. The concentration of metals was measured by Inductively Coupled Plasma Optical Emission Spectroscopy (ICP-OES). Metal concentrations were compared with the United States Environmental Protection Agency (USEPA) and California Department of Toxic Substances Control (CDTSC) standards. Results: The results showed that the average concentration of metals in both WET and TCLP methods was high, but the concentration of most metals in WET method was relatively higher than in TCLP method. Conclusion: The results showed that the recovery of metals from batteries is necessary, moreover safe burial of batteries is essential to reduce environmental risks.

Assessment of heavy metal concentrations in blood and radon concentrations in urine samples of workers at selected building material factories in Erbil, Iraq

ABSTRACT A total of 90 blood and urine samples were assessed to evaluate the health risks associated with radon and heavy metals in the Erbil Governorate. The worker group from the building materials manufacturers provided 70 samples, while an additional 20 samples were obtained from a control group. X-ray fluorescence technology was employed to measure and analyse the heavy metal content in the collected blood samples, while radon levels in the urine samples were analysed using a CR-39 detector. The findings indicate that the working group exhibits greater levels of radon and heavy components (Pb, Cd, and Ni) compared to the control group. The statistical analysis revealed that the levels of radon in urine samples of workers were significantly different (p ≤ 0.001) in certain factories, such as the cement plant, lightweight block, and red brick factories, compared to the control group. However, the levels were not statistically significant in other factories. The test showed significant differences in Pb concentrations between the employed and control groups (p < 0.05), with higher average values of Cd and Ni, but not statistically significant (P ˃ 0.05). The study found a positive correlation between the duration of employment and the average concentration of heavy metals (Pb, Cd, and Ni) in workers’ blood samples. Additionally, smokers and non-smokers had significantly different mean heavy element levels in their blood samples (p < 0.05). There is no statistically significant correlation between smoking status and radon levels (P ˃ 0.05). Remarkably, each urine sample had radon levels below the 200 Bq/m3 International Atomic Energy Agency standard, suggesting that urine is impurity-free. These results are critical and serve as baseline data in the Kurdistan region.

Geochemical Modeling and Quality Assessment of the Surface Waters from the Mouhoun River System, Burkina Faso: Implications of Water–Rock Interactions and Anthropogenic Activities

Major ion and heavy metal geochemistry was used to investigate the factors that control the Mouhoun River water quality in western Burkina Faso. Major cation concentrations was in the following decreasing order: Ca2+&gt; Na+&gt; K+&gt; Mg2+, reflecting silicate weathering. However, relatively high HCO3- and SO42- concentrations could be related to dissolution of calcite and sulfide minerals, respectively. The average heavy metal concentrations in the riverine system were in the following order: FeT&gt;Ag&gt;Mn&gt;Zn&gt;Pb&gt;Cu&gt;Ni&gt;AsT&gt;Cr&gt;Hg&gt;Co&gt;Cd with FeT and Ag exceeding the World Health Organization permissible limits. Concentrations of all heavy metals, except Cr, were higher in the Mouhoun system compared to the average world river concentrations. Adsorption and speciation models showed that Zn, Ag, Cd, Co, Cr and Ni are likely to remain in their free ionic forms, and thus posing serious threats to aquatic life and human health. Ag-Hg-Ni-Cd association around Poura and Tenado on the principal component plot suggested that the widespread artisanal gold mining in these areas may have contributed to these metals’ loading. In contrast, NH4+, Pb, Cu, Cr, AsT and Zn were clustered around a densely populated and industrialized Kou watershed, pointing to agricultural and industrial sources of these pollutants. Furthermore, the Kou River had the highest metal index followed by Tenado, Samendeni, Poura and Boromo. Hence, the chemistry of the Mouhoun River and its tributary appears to be mainly controlled by population density and various anthropogenic activities taking place in their drainage basins. The findings could provide avenues for sound and sustainable water resource management in a water scarce semi-arid environment.

Heavy metal contamination in soil and food crops and associated human health risks in the vicinity of Iringa Municipal dumpsite, Tanzania

Heavy metal contamination and potential risks to human health related to consuming major food crops near Iringa Municipal dumpsite are presented. Soil samples, maize (Zea mays L.) and common beans (Phaseolus vulgaris L.) were collected downslope around the dumpsite during wet season. Soil samples were analyzed using Energy-Dispersive X-Ray Fluorescence (EDXRF) while crop (maize and beans) samples were analyzed using Flame Atomic Absorption Spectrophotometer (FAAS). The potential health risks associated with human exposure to heavy metals in maize and common beans was evaluated according to the method prescribed by the United States Environmental Protection Agency. The concentrations Cd (3.25–10.78 mg/kg), As (1.84–10.98 mg/kg) and Ni (71.74–55.10 mg/kg) in soil samples exceed the maximum allowable limits set by Tanzania Bureau of Standards (TBS). The average heavy metal concentration in food crops followed the trend Cd, As < Cr, Pb < Ni < Cu < Mn < Zn with Pb in maize (0.96 mg/kg) and common beans (0.81 mg/kg) above FAO/WHO regulatory standards of 0.3 mg/kg. This implied health concerns to consuming food crops grown in the vicinity of the dumpsite. Further, lifetime–incremental cancer risk (ILCR) assessment suggest that consuming maize and common beans from the study area could increase the risk of both cancer and non-cancerous diseases in both adults and children. However, the degree of ILCR in children was noticeably higher (1.0 × 10–2) than in adults (5.10. × 10–6) for Pb in common beans. Therefore sustainable waste management should be stressed and continuous monitoring of environments around dumpsites is crucial to mitigate the negative impacts on public and environments.

Contamination of toxic elements in the sediments, water, and igneous rocks of the Sefid-rud River in Northern Iran using contamination indicators, with a specific focus on Ti-rich coastal sediments

The Sefid-rud River is a significant river on the southern coast of the Caspian Sea in Iran. In this study, we collected 28 samples of surface sediments and water to assess the level of metal contamination. Chemical analysis revealed that the average concentrations of heavy metals in both sediments and water increase from upstream to downstream. There is no clear significant relationship observed between changes in the values of investigated elements in sediments and water. The levels of these elements in the sediments, exceed toxic response thresholds. In the water samples, As, Ni and V concentrations exceed the WHO standard values. According to the Igeo, EF and PLI indices, the sediments at most stations are not contaminated by any of the elements. The CF and Dc indices suggest low contamination levels at all stations. The NIPI and ecological risk indices (Er and RI) indicate non-polluted conditions at all stations except SF22, SF20, SF11, and SF6. The MI and HEI indices indicate pollution in all water samples of the Sefid-rud, but critical values are only observed at SF5 and SF15. The other stations show no contamination. The Cf index indicates high pollution levels for all elements except Cu, Zn, and Pb. The upstream area poses a relatively high and considerable ecological risk according to the PERI index. In conclusion, the sediments of the Sefid-rud River have a higher potential for the exchange of toxic substances compared to the aquatic environment.

Natural radioactivity and heavy metal contamination in edible fish, shellfish and mollusks at the Bay of Bengal, Kuakata, Bangladesh

In this study, gamma activity concentrations, gross alpha and gross beta activity of natural radionuclides, and heavy metal concentrations were measured in eleven edible marine fish, four shellfish, two mollusks, and a common seaweed sample collected from a local sea fish market and sea beach area of the northern part of the Bay of Bengal, Kuakata, Bangladesh. Using HPGe gamma spectrometry, the activity concentrations of 238U, 232Th, and 40K were measured and found to be 19.7 ± 1.5 Bq/kg, 12.2 ± 0.9 Bq/kg, and 188 ± 15 Bq/kg, respectively, with the 232Th concentration surpassing that of 238U. The ZnS scintillation detector was used to assess the gross alpha and gross beta activity. The average gross alpha activity and gross beta activity were found to be 9.4 ± 1.4 Bq/kg and 26 ± 4 Bq/kg, respectively, with the latter attributed to beta emitting radionuclides's abundance. The activity concentrations of 238U, 232Th, and 40K in the analyzed samples varied in the order of Shellfish > Seaweed > Fish > Mollusks, Seaweed > Shellfish > Mollusks > Fish, and Seaweed > Shellfish > Fish > Mollusks. The annual effective dose due to consumption of analyzed seafood was found to be within the world limit of 2400 μSv/y recommended by UNSCEAR. The main contributor to the annual effective dose was 238U. The excess lifetime cancer risk (ELCR) results were below the permissible threshold of 10−3 for radiological risks. Furthermore, average concentrations of Zn and Mn were higher than WHO/FAO recommended values, and carcinogenic Pb, Cd, Cr, and Hg concentrations were below detection limits, according to heavy metal analysis performed by AAS. The average concentration of heavy metals in all of the seafood samples under investigation was in the order of Zn > Fe > Mn. The calculated hazard index (HI), target hazard quotient (THQ), and estimated daily intake (EDI) were compared to the permissible safety limits.

Hazard and Health Risk Assessment of Heavy Metals in Non-Alcoholic Beverage Consumed in Abia State, Nigeria

The quality of non-alcoholic beverages consumed in Aba, Abia State, southeastern Nigeria and health risk assessment of heavy metals required periodic evaluation so as to avert potential health hazard. Hence, the objective of this paper as to evaluate the hazard and health risk assessment of heavy metals in non-alcoholic beverages consumed in Abia State, Nigeria using health risk assessment models. Heavy metals concentrations were determined using atomic absorption spectrophotometer (Agilent 280FS AA). The average heavy metal concentrations of non-alcoholic drink samples ranged from 0.040 - 1.132 mg/l in ascending order of Zn &lt; Cd &lt; Co &lt; Cu &lt; Pb &lt;Cr &lt; Mn &lt; Fe respectively. The average concentrations of Mn, Cr, Cd, Fe and Pb exceeded the standard maximum permissible limits for drinking water quality. The values of estimated daily intake for Cd, Fe, Pb, Cr, Mn and Zn were within acceptable provisional tolerable daily intake and safe limits. The hazard quotient (HQ) values for Mn, Cr, Cd, Zn and Fe were within safe limit (&lt; 1.0), except for Co and Pb that had HQ values greater than one in over 37.5 % of the total samples, indicating associated potential chronic health risks. Hazard index of 72.5% of all the non-alcoholic drink samples were above the safe limit (&gt;1.0), signifying potential chronic health risk as a result of combine effects of these heavy metals. The incremental life cancer for Cr, Cd and Pb ranged from 2.59E-05 - 1.79E-03, 1.35E-04 – 2.81E-04 and 3.92E-06 - 3.24E-05 respectively. The incremental life cancer values of Pb were within the recommended safe limit of not greater than 1.0 × 10-4 and has the least likelihood of any potential cancer risks. However, Cd, and Cr had cancer risk values higher than the save limits, indicating potential life cancer health risks in both children and adult population.