Heavy Metal Concentrations In Water Research Articles

Heavy metal concentrations in water, sediments, Cladophora and two fish species from Al-Masab Alamm River, Al- Nassiriya, Iraq

Heavy metal concentrations in water, sediments, Cladophora and two fish species from Al-Masab Alamm River, Al- Nassiriya, Iraq

Assessment of Heavy Metals Concentration in Water and Fish of Dalmaj Marsh, Iraq

Most marshes in Iraq face several challenges as aquatic environments, including pollution by various chemical agents and heavy metals. The current study deal with an analysis of the water quality of Dalmaj marsh as one of the closed aquatic environments in the middle parts of Iraq located between latitudes 32ᵒ 05′ to 32ᵒ 23′N and longitudes 45ᵒ 10′ to 45ᵒ 38′ E. The marsh is suffering from a shortage in water supply, especially during the summer. It will lead to a concentration of heavy metals that are washed and transported to the marsh from the surrounding watersheds through surface runoff. This work aims to analyze water and fish samples to assess heavy metals and their accumulated risk in fish tissues based on many indices. The 16 samples of water and nine samples of fish are collected and analyzed for concentration of heavy metals, i.e., Lead (Pb), Chromium (Cr), Nickel (Ni), Cadmium (Cd), Copper (Cu), Zinc (Zn). The water analysis results indicate that Chromium (Cr) only comes below the permissible limit in water. At the same time, the composite heavy metals pollution index (HPI) identified that the water samples are varied from light pollution to malignant pollution. Regarding fish samples, three indices, i.e., BAF, EDI, and HI, are used to test the accumulated concentration of heavy metals in fish tissues and to point out their risk to consumers. The results indicate that Pb and Ni are the more hazardous metals accumulated in many fish samples with increasing fish weight, while hazard index (HI) is an additive index of all tested heavy metals, indicating concern risk from most fish samples. The study recommends testing the marsh water pollution periodically.

Determination of heavy metals concentration in water and sediment of river donga, Taraba state

This research was carried out to ascertain the heavy metals concentrations in water and sediments from River Donga upstream and downstream was investigated for a period of three months (October to December). The Result showed heavy metals concentrations were higher in sediments compare to water during the study period while downstream values were generally higher compare to upstream. Result for mean concentration of heavy metals variations in water and sediment varied significant (p>0.05) based on the two sampling locations upstream and downstream. The heavy metals concentration in water and sediments was examined using atomic absorption spectrophometer (AAS) Bulk scientific Model 210VGP. Concentrations ranking profile was found to be Zn >Ni>Pb >Cr>Cd. The maximum mean concentration of Zn recorded in the sediment was 0.700 mg/kg while the lowest value of 0.029mg/kg was recorded for Pb at the two locations while for water value (0.200 mg/l) were observed for Zn, Ni, and Cr in the months of October November and December respectively. The lowest value of 0.014mg/1 at both locations was recorded for Cr. Data for Cr, Ni, Pb. Pb were generally low throughout the study period. Zn concentrations in water at the sampled locations (upstream and downstream) throughout the study periods showed no significant difference (p>0.05). However, Cd, Cr, Pb and Ni show variations (p

Heavy Metal Content of Water in Ikwu River (Umuahia, Nigeria): Pollution Indices and Health Risk Assessment Approach

The heavy metal content of a local drinking water source in Southeast Nigeria was studied between January 2021 and June 2021 in 3 stations. Pollution indices (heavy metal pollution index and contamination index) and health risk assessment for non-carcinogenic were used to check the water’s suitability for human consumption. Eight heavy metals were assessed with standard methods and compared with The Nigerian Drinking Water Quality Standard. Some metals (Mn, Pb, Fe, Cd, and Cr) exceeded acceptable limits. The heavy metal pollution index exceeded the threshold value (100), ranging between 503.56 and 746.80. The contamination index ranged between 10.74 and 17.12 indicating high contamination potential and all the hazard indices exceeded unity (1). The heavy metal content, pollution indices, and health risk assessment has shown that the water from the Ikwu River was not fit for human consumption. The main metals that influenced the results were Mn, Pb, Fe, Cd, and Cr, because they exceeded limits while Cd and Cr were responsible for the observed adverse health risk. The children were more vulnerable. The geogenic influence was a major factor exacerbated by season and anthropogenic activities in the river.

Assessment of heavy metal concentration in water and the Nile tilapia of Lake Manzala, EL-Kapoty, Egypt

Assessment of heavy metal concentration in water and the Nile tilapia of Lake Manzala, EL-Kapoty, Egypt

The Analysis of Heavy Metal Transport Mechanism and Electrolytic Reduction Method for Remediation of Agricultural Ditches

The complex sources of heavy meatal pollution in agricultural lands include: inappropriate discharge, contaminated irrigation water, fertilizer application and atmospheric fallout. The excessive heavy metal concentration can affect crop production and quality. In Taiwan, there are more than 1000 hectare of contaminated agricultural lands, which are mainly located in Taoyuan, Changhua and Kaohsiung. This study aims to analyze the heavy metal concentration in water and the bottom mud to establish the water-sediment heavy metal transport model for the agricultural ditches, Sankuaizho, in Taoyuan, and further evaluate the effect of heavy metal desorption by the electrolytic reduction method. The research results showed that the water body of the Sankuaizho is mainly polluted by heavy metals such as Cu, Ni, and Zn, but only Cu exceeds the water quality standard for irrigation (> 0.2 mg/L). The sediment is polluted by heavy metals, such as Cr, Cu, Ni, Pb and Zn, especially Cu pollution is the most severe one. The electrolytic reduction method could effectively remove heavy metals from bottom mud in terms of the electrolytic reduction efficiency ranged between 43.93% and 97.52%. The WASP simulation results showed that the concentration of heavy metals (copper, zinc, and nickel) at the most downstream (segment 7) are highest when mixed with the polluted water from the upstream flow, which is mainly resulted from the effluent from the electronics factory. Compared to the observed data, the MAPE values of model simulation results are: copper = 47.12%, zinc = 26.62%, nickel = 36.66%, showing that the WASP model performs well and reasonably. The research results of this study could be used as a reference for future decision making to improve the water quality and solve the bottom mud issues.

The effects of roadways on lakes and ponds: a systematic review and assessment of knowledge gaps

As the global population increases, the expansion of road networks has led to the destruction and disturbance of terrestrial and aquatic habitats. Road-related stressors have significant effects on both lotic and lentic habitats. While there are several systematic reviews that evaluate the effects of roads on lotic environments, there are none that consider their effects on lentic habitats only. We conducted a literature review to achieve two objectives: (1) to summarize the effects of roads on the physical, chemical, and biological properties of lentic environments; and (2) to identify biases and gaps in our current knowledge of the effects of roads on lentic habitats, so that we could find promising areas for future research.Our review found 172 papers published between 1970 and 2020. The most frequently studied stressors associated with roads included road salt and heavy metal contamination (67 and 43 papers, respectively), habitat fragmentation (37 papers), and landscape change (14 papers). These stressors can lead to alterations in conductivity and chloride levels, changes in lake stratification patterns, increases in heavy metal concentrations in water and organisms, and significant mortality as amphibians disperse across roadways. We also identified a variety of other stressors that may be understudied based on their frequency of appearance in our search results, including polycyclic aromatic hydrocarbons, road dust, increased accessibility, hydrological changes, noise pollution, dust suppressants, sedimentation, invasive species introductions, and water withdrawal.Our review indicated that there are strong geographic biases in published studies, with 57.0% examining North American sites and 30.2% examining European sites. Furthermore, there were taxonomic biases in the published literature, with most studies focusing on amphibians (41.7%), fish (15.6%), and macroinvertebrates (14.6%), while few considered zooplankton (8.3%), diatoms (7.3%), amoebas (5.2%), water birds (3.1%), reptiles (2.1%), and macrophytes (1.0%). Based on our review, we have identified promising areas for future research for each of the major stressors related to roadways. However, we speculate that rectifying the geographic and taxonomic bias of our current knowledge could significantly advance our understanding of the impacts of roads on lentic environments, thereby better informing environmental management of these important habitats.

Comparative Evaluation of Heavy Metal Concentration in Water and Sediment, Choba Segment of New Calabar River, Port Harcourt, Nigeria

The heavy metal concentration in water and sediment, Choba segment of New Calabar River, Port Harcourt was investigated between February and April, 2020. Samples collected from the three locations were analysed in the laboratory for heavy metals using Atomic Absorption Spectrophotometer (AAS) following standard method of APHA. The mean values of heavy metal in water (mg/l) were: Cr (2.29±1.29), Ni (2.32±0.28), Pb (2.46±0.38), Cd (0.04±0.02), Fe (52.18±7.26) while that of sediment were: Cr (7.18±0.43), Ni (5.57±0.29), Pb (8.09±0.39), Cd(0.30±0.15), Fe (123.64±5.17). The heavy metal values showed variations across the stations at P<0.05. The order of concentration of heavy metal in water was: Fe>Pb>Ni>Cr>Cd while that of sediment is Fe>Pb>Cr>Ni > Cd with heavy metal concentration in sediment higher than that of water while Fe and Cd concentrations were highest and lowest in both water and sediment respectively. All the heavy metals in water except Ni exceeded the permissible limits of World Health Organisation (WHO), Federal Environmental Protection Agency (FEPA) while that of sediment were below the permissible limits except Fe. It was concluded from the results that Choba segment of the New Calabar River is under stress since the heavy metals apart from Nickel (Ni) present were above the permissible limit. This implies that the quality of the water is unsafe for use especially for domestic purpose if untreated owing to the on-going anthropogenic activities in the area. Therefore, regulatory standards for discharges from anthropogenic activities should be strictly controlled

Seasonal Dynamics of Heavy Metal Concentrations in Water and Fish from Hakaluki Haor of Bangladesh

Food safety is currently a serious concern due to the health risks associated with food intake, particularly due to heavy metal contamination. Therefore, the present study was conducted to investigate the heavy metals concentration in water and fishes collected from Hakaluki haor, Bangladesh. Three important fish species, Labeo rohita, Cirrhinus cirrhosis, and Labeo calbasu, together with water samples, were analyzed for heavy metals (Pb, Cr, and Cd), respectively. Considering four seasons, namely the monsoon, post-monsoon, winter, and pre-monsoon, a total of 72 fish samples were collected from three fishing stations from June 2017 to May 2018. The results showed that the total mean concentration of metals in water (mg L−1) was found to be in the order of Pb (0.125 ± 0.058) > Cr (0.026 ± 0.012) > Cd (0.001 ± 0.0002) within the maximum permissible limits set by the EU and WHO, except for Pb concentrations. Similarly, the total mean concentrations of Pb in fish (µg g−1) were found in order of L. rohita (0.388 ± 0.291) > Cirrhinus cirrhosus (0.334 ± 0.236) > L. calbasu (0.251 ± 0.117) greater than the maximum permissible limits (0.3 µg g−1) set by FIQC, except for L. calbasu. However, the mean concentrations of Cr and Cd in fish were found to be below the maximum permissible limits of FAO and FIQC, respectively. The quantity of heavy metal contamination in this haor indicates that the situation is worrying for the region’s biota and residents. However, to protect public health and reduce environmental risk, the appropriate authorities should oversee and monitor it with strong hands.

Heavy metal concentration in water, soil and cultivated vegetables at the edge of Kashaf Roud River, Mashhad, Iran: ecological risk assessment and bioaccumulation factor

ABSTRACT The entrance of heavy metals through human activities causes pollution of water, soil, and plants. The aim of this study was to measure the heavy metals concentration (Hg, Pb, As, and Cd) and their ecological impacts on water, soil, and vegetables in the Kashaf Roud River basin. Hence, 72 samples of irrigation water, 72 samples of soils, and 216 samples of vegetables (dill, leek, and basil) were collected. The contamination levels were evaluated by several ecological indices including Ecological Risks index (ERI), Heavy Metal Evaluation Index (HEI), Contamination factor (Cf), Pollution Index (PI), geo-accumulation index (Igeo), Potential ecological risk index (RI), Pollution load index (PLI), and modified degree of contamination (MDC). Based on obtained results, concentrations of heavy metals in water and soil samples were in the order of Pb>As>Cd>Hg. In addition, Pb and As had the highest concentration in vegetables with the mean total concentrations of 1.60 and 0.08 mgkg−1 wet weight, respectively. According to ERI value (238), water sampling site no. 3 had higher pollution than other places and was classified in the considerable ecological risk. Among the soil samples, the Cf average values followed the declining order of Cd (7.78)>Pb (6.91)>Hg (4.26)>As (2.68), so that Pb and Cd presented high contamination levels. Moreover, all soil samples of the studied region possessed PLI>1, which confirms their contamination with heavy metals. Finally, the trends in the BAF values for heavy metals in various vegetables were in order of Hg>Cd≈Pb>As for Leek and Hg>As> Pb>Cd for Dill and Basil. Concentrations of heavy metals in soil and water samples were within the national and international standard ranges. However, the concentrations of these metals in some vegetable samples exceeded the national and international levels. The utilisation of standard quality effluent for agricultural irrigation requires control measures and good organisational performance.

Determination of Heavy Metals Concentration in Water and Soil at Various Locations in Lahore and their Harmful Impacts on Human and Plants life

Heavy metals poisoning of soil and water has resulted from industrial expansion in Lahore, Pakistan, creating a significant environmental hazard. As a result, monitoring the contamination of soil and water around industrial sites is critical. The fact that higher concentrations of heavy metals have a negative influence on both plants and human life and this cannot be ignored. Higher heavy metal concentrations have a direct impact on human health due to their presence in drinking water. Consumable plants and vegetables cultivated in these polluted areas may collect higher concentrations of heavy metals from soil and water via the phytoremediation process. Its worth mentioning that the accumulation of toxic metals in edible plants and vegetables also has a direct negative impact on human and animal health. The purpose of this study is to find the heavy metals concentration in the soil and ground water in the Lahore area. Five industrial zones were evaluated for water and soil throughout the research period of December 2021 to January 2022 (pre-monsoon). pH and heavy metals content measurements were performed on the collected soil and water samples. We discovered that the water had a higher pH and that the soil was heavily contaminated with significantly higher concentrations of toxic heavy metals. According to the research, there is a gangrenous influence of pollution caused by industrial waste and the surrounding environment on soil and water resources, which affects living creatures. Keywords: Environmental Pollution, Heavy Metal, Pollution, Water pollution, Soil pollution

Assessment of heavy metal concentrations as indicator of pollution in Clarias gariepinus (African catfish) of Warwade reservoir, Dutse, Jigawa State-Nigeria

Pollution status of Warwade reservoir was assessed using heavy metals bioaccumulation in water, gills and liver samples of C. gariepinus between July and December, 2019. Heavy metals analyses were carried out using microwave plasma atomic spectroscopy (MP-AES). Water and fish were sampled fortnightly from the three sites coded as upstream (A), midstream (B) and downstream (C) between 7:00 – 7:30am for period of six months. The results revealed that heavy metal concentrations in water followed the order: Cr (2.15mg/L)>Cu (1.40mg/L) > Pb (0.89mg/L)> Cd (0.68mg/L). Bioaccumulation Factor (BAF) of heavy metal concentration in water decreased in the order of Cr > Pb > Cu >Cd. In the fish organs, gills had the highest value of Cr, followed by Pb, Cu and Cd recorded the lowest. The BAF in liver tissues decreased in the order of Cu > Pb > Cr >Cd. BAF for Cu was highest in liver tissue (2.90) while the lowest was obtained in the gills (1.04). Lead (Pb) had its highest value in liver (2.16) and the lowest value (1.33) was obtained in the gill. BAF in Cr had its highest value of 2.15 in water and the lowest was obtained in the gills. Heavy metals bioaccumulation differed significantly (p<0.05) between the sampling sites and seasons with the exception of cadmium which did not differed significantly (p>0.05). It can be deduced that heavy metals bioaccumulation in the fish tissue is attributed to the influx of chemicals into the reservoir as a result of agrochemicals input among other anthropogenic activities. It is recommended that indiscriminate release of the xenobiotic compounds should be minimized in order to avert degradation of the reservoir in the long run. Intervention by appropriate authorities to curtail the effects of heavy metals on fish species among other important biota is recommended.

Physico-Chemical Properties of Sediments from Some Water Sources in Buea, Southwest Cameroon: Ecotoxicological Implications

Sediments form a natural buffer and filter system in the material cycles of waters. They qualify total ecosystem of a body of water because they reflect the long-term quality situation as well as current inputs. This study aimed at assessing the physico-chemical properties of sediments from some water sources in Buea, following varied anthropogenic activities and their ecotoxicological implications. Water and sediment samples were collected following standard procedures. Spatial variations in these parameters were observed. Comparing the mean heavy metal concentration in water across the categories, DW had the highest concentration for Cu (0.19 mg/L). MW and DW had the highest concentration for Zn with 0.25 mg/L each. Pb was highest in MW category (0.26 mg/L) and CM had the highest Cd concentration (0.30 mg/L). Mean heavy metal concentration of sediments across the categories showed that Cu, Zn and Pb were highest in DW category (0.89 mg/kg, 1.41mg/kg and 1.41 mg/kg respectively), while Cd was highest in CM with a value of 7.78 mg/kg. The presence of the metals in both water and sediments are explained by anthropogenic inputs as well as the other physico-chemical properties of the sediments including pH and particle size. These systems present potential threat to life along the food chain, necessitating protection measures. Keywords: Physico-chemical properties, sediments, water sources, Buea, Ecotoxicological implications DOI: 10.7176/JEES/12-4-05 Publication date: April 30 th 2022

Accumulation potential of heavy metals at different growth stages of Pacific white leg shrimp, Penaeus vannamei farmed along the Southeast coast of Peninsular India: A report on ecotoxicology and human health risk assessment

This study compared the heavy metal concentration in water, sediment, and shrimp at different growth stages of culture and subsequently evaluated the ecotoxicological and human health risk status. Total trace element concentration in the water, sediment and shrimp ranged from not detected (ND) (Hg) to 91.05 (Fe) μg/L, 0.01 (Hg) to 19, 246.33 (Fe) mg/kg, and ND (Hg) to 13.98 (Fe) mg/kg, respectively. Toxic metals such as, Cd, Hg, and Pb in shrimps ranged from ND to 2.11 mg/kg, ND to 0.158 mg/kg, ND to 0.088 mg/kg, and ND to 0.469 mg/kg, respectively. Toxic heavy metals at all the growth stages of shrimps (days of culture (DOC)-01 to DOC-90) were found below the maximum residual limit (MRL) of 0.5 mg/kg set by the European Commission (EC). Similarly, Cu, Zn, and As concentrations in shrimp were also far below the MRLs of 30 mg/kg, 100 mg/kg, and 76 mg/kg set by the World Health Organization and Food Safety and Standard Authority of India, respectively. The concentration of heavy metals increased from DOC-01 to DOC-90 and was positively correlated with the length and weight of the shrimps (p < 0.05). The risk assessment was estimated for both Indians and Americans and found no carcinogenic (lifetime cancer risk (LCR) < 10−4) and non-carcinogenic (THQ and TTHQ<1) health risks through consumption of shrimp cultured in this region. The hazard quotient (HQdermal < 1), hazard index (HI < 1), and LCR (<10−4) values of the heavy metals indicated that the dermal absorption might not be a concern for the local fishermen and marine fish/shrimp farmworkers. Water and sediment quality indices were applied to assess the surface water and sediment quality, and their results were found nil to low levels of heavy metal contamination at all the sampling sites. All heavy metals studied in sediments were < effect range low (ERL) and < threshold effect level (TEL), indicating no adverse biological effects on aquatic organisms. Therefore, regular monitoring of the shrimp aquaculture system throughout the crop will provide evidence of heavy metals bioaccumulation in shrimps. This research will provide baseline data to help farmers establish the optimal aquaculture practices and regulatory authorities to formulate legislation and strategies to reduce heavy metal biomagnification in shrimps from farm to fork.

Boraboy Lake from Amasya Turkey: natural radioactivity and heavy metal content in water, sediment, and soil

Boraboy Lake from Amasya Turkey: natural radioactivity and heavy metal content in water, sediment, and soil

The Nutrient and Heavy Metal Contents in Water of Tidal Creek of the Yellow River Delta, China: Spatial Variations, Pollution Statuses, and Ecological Risks

In order to understand the spatial distribution, ecological risks, and pollution status of nutrients and heavy metals in the coastal tidal creek water of the Yellow River Delta (YRD), a total of 21 water samples were collected from 7 sample sites. The results indicated that along the coastline from northwest to southeast in the YRD, the concentrations of TN, TP, and NH4+-N in the water decreased and then increased; the Cu concentration increased, decreased, and then increased; and the Pb concentration decreased. The average TN/TP mass ratio indicated that the tidal creek water belonged to a potential phosphorus-restricted eutrophication state. The RI result indicated that Cu and Pb in the water were at low ecological risk, while the SSD and RQ results indicated that Cu in the water was at a high ecological risk level and had potential harm to aquatic organisms. Based on the single-factor method, the water quality of the tidal creek inside and outside the Yellow River Delta Nature Reserve belonged to Grade IV. Cu should be controlled to improve the water quality and reduce the ecological risk, especially in the Yellow River Delta Nature Reserve.

Mercury, Lead, and Cadmium Heavy Metal Content in Water, Fish, and Sediment in Limboto Lake

Lake Limboto is the largest lake in Gorontalo province including 15 Lake baggage that will be restored by the government. Pollution occurring in Lake waters is an important issue that needs to get the attention of various parties. Research aims to determine the status of environmental quality of the area, reviewing heavy metals (Hg, Pb, Cd) in water fishes and sediments, knowing the correlation between the fish and sediment. Sampling method is performed on 12 sampling points specified in purpose sampling. The method of analysis is used with government regulation No. 82 year 2001 on water quality and pollution control, measurement of heavy metal concentration SNI 06-6992.2.2004 by using Atomic Absorption Spekphotometer (AAS). The mercury content (Hg) of water in the 0.0019-0.1216 ppm range has exceeded the limits based on quality standards, lead (Pb) ranges between 0.008-0.0463 ppm while cadmium levels (Cd) range 0.007-0.0085 mg/L in general the value difference between stations is not Much. The content of mercury heavy metals in fish 0.0079-0.0631 as well as the heavy metal content of Pb is 0054 mg/L while the cadmium (Cd) content 0.017-0.058 mg/L. The concentration of heavy metals Hg 5.81-5.72 mg/L, the average Pb heavy metal 0.5571 mg/L whereas the heavy metal cadmium 0.6190 mg/L. The correlation of heavy metal mercury with water is an index of 1.00 showing strong relationships while the correlation of the heavy metals Pb 0233 has a weak and negative relationship and the Cd heavy metal is the 0.019 that shows a low correlate.

Comprehensive assessment of heavy metals contamination in soil and water in peri-urban areas of National Capital Territory, Delhi

Contamination of soil and irrigation water by heavy metals (HMs) is a genuine concern due to the possible effect on human well-being via food chain. Thus, an assessment was carried out to find HMs concentration level in water and soil samples of peri-urban areas of National Capital Territory (NCT) Delhi. Analytical results revealed that significant amount of HMs concentration were found in irrigation water, out of which concentrations of Cu (2590 ?g/L), Fe (5549 ?g/L), Cr (1910 ?g/L), Mn (2570 ?g/L), Zn (2155 ?g/L) and Cd (405 ?g/L) in drain water were exceeded the permissible limit of FAO. Cu (108.94 ?g/g) and Pb (163 ?g/g) concentration in surface soils of majority of sites were recorded beyond the permissible limit of FAO. The overall mean HMs concentration in soil found in the sequence Zn&gt;Cu&gt;Fe&gt;Mn&gt;Cr&gt;Ni&gt;Pb&gt;Cd. It reveals that increasing trend of HMs concentration in water used for irrigation results in metal accumulation in soil, and their consequent accrual in the crops lead to adverse impact on human well-being.

The Accumulation and Transformation of Heavy Metals in Sediments of Liujiang River Basin in Southern China and Their Threatening on Water Security.

Heavy metal (HM) pollution in sediments is tightly related to the security of water quality in rivers, but the accumulation and conversion of HMs are poorly researched, so that a field study was conducted as an example in the Liujiang River Basin. Seven HMs were analyzed to determine between the overlying water and sediments. Moreover, the regulation of HMs speciation and environmental factors in their accumulation and conversion were identified. The obtained results suggested the HM concentrations in water are far below the primary standard of water quality, but in sediments, the contents of Cd and Zn are significantly higher than their corresponding baseline of soil. Only Cd and Pb are dominantly in non-residual form (carbonate-bound fraction and reducible fraction, respectively). The non-significant correlations suggested pH and Eh may be hard to influence HMs in water, while the significant correlations highlighted the regulations of Eh, organic matter and mean grain size on the accumulation of metals in sediments. The opposite correlations between EC, TDS, pH and Cd confirmed the emission of acid wastewater contributed to the accumulation of Cd in sediment. The conversion of metals between water and sediments were found to be significant only in specific forms of Cd, As, Cu, Zn and Pb, suggesting the conversion of HMs in sediments should be largely regulated by their specific forms. The very high risk disclosed by the higher values of and RI are only found upstream, while the higher risk of Cd should be treated as a critical environmental threat.

Possible health risk assessment for heavy metal concentrations in water, sediment, and fish species and Turkmen pregnant women's biomonitoring in Miankaleh Peninsula, Iran.

This study investigated the human biomonitoring of heavy metals in the water, sediments, and tissues of mostly consumed fish species using Turkmen pregnant women's biomarkers in winter 2019, at the Miankaleh Peninsula, north of Iran. Metal concentrations were measured in various fish organs as well as pregnant women's blood, hair, and nail as biological indicators. For this purpose, a total of 20 water and sediment, 14 fish, and 16 human samples were collected. Inductively coupled plasma mass spectrometry (ICP-MS) was used to evaluate the concentration of Cr, Co, Cu, As, Hg, and Pb. Results showed metals with the highest concentrations as Cu and Cr in water (93.35 and 80.91µg/l, respectively), Hg and Pb in sediment (7.40µg/g for both), Cu and Pb in the liver (27.00 and 18.9µg/g for C. carpio; 1414 and 31.7µg/g for L. auratus), muscle (10.00 and 18.80 for C. carpio; 37.20 and 8.27µg/g for L. auratus), and skin (26.40 and 9.90 for C. carpio; 10.80 and 11.74µg/g for L. auratus). In addition, Cu, in pregnant women samples, had the highest values at 2.53mg/l, 8.87, 36.46, and 29.04µg/g for blood, hair, fingernail, and toenail, respectively. However, Co showed the lowest concentration in all studied samples. Fish liver and fingernail of pregnant women did reveal the highest heavy metal accumulation, whereas fish muscle and blood of pregnant women had the lowest accumulated heavy metals. The concentration of Hg in water, sediment, fish muscle, and women's blood and hair exceeded the limits suggested by various organizations. Therefore, this study highlighted that heavy metal concentration, in particular Hg, in water, sediments, and fish is a serious risk to the health of local inhabitants who rely on fisheries products and recommended that necessary information should be provided to warn Turkmen pregnant women in consumption of Hg-contaminated fish in this area.