Distribution and ecological assessment of heavy metals in surface sediments of the East Lake, China

Concentrations and risk assessment of chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), lead (Pb), cadmium (Cd) and mercury (Hg) were investigated in 106 samples of surface sediments from the East Lake, China in this study. The mean concentration of Zn was highest among the eight heavy metals (225 mg kg^?1), followed by As (191 mg kg^?1), Cr (145 mg kg^?1), Cu (55 mg kg^?1), Ni (27.1 mg kg^?1), Pb (7.93 mg kg^?1), Cd (0.94 mg kg^?1) and Hg (0.21 mg kg^?1). Niuchao Hu was less polluted by heavy metals compare to the other four lakelets of the East Lake. The correlations among these heavy metals and the results of principal component analysis indicated that the distribution of Cd, Pb and Hg was related to anthropogenic activities, whereas Cu, As and Cr were affected by the parent rocks. Zinc and Ni were influenced both by anthropogenic activities and parent rocks. Based on the Sediment Quality Guidelines, the results of toxicity assessment indicated that adverse effects caused by Cr and As would be expected frequently. Nickel, Zn, Cd and Hg may cause adverse effects occasionally and Cu and Pb may cause toxicity infrequently. Arsenic was found to have the highest acute toxicity by toxic units (TUs), followed by Cr, Ni, Zn, Hg, Cu, Cd and Pb. The potential ecological risk index analysis indicated that As, Cd and Hg had considerable or high ecological risk, whereas Cr, Ni, Cu, Zn and Pb had low ecological risk. The potential ecological risk index (RI) of the heavy metals in the surface sediments of East Lake was 483, indicating considerable ecological risk. Close attention should be paid to pollution of the heavy metals in East Lake, China.     

Potential ecological risk of heavy metals and metalloid in the sediments of Wuyuer River basin,Heilongjiang Province,China

The spatial distribution, sources, and potential ecological risk of heavy metals and metalloid were evaluated in sediments of the Wuyuer River and its tributaries. Metal and metalloid concentrations and chemical speciation (Cr, Cu, Ni, Pb, Cd, As, Zn and Hg) in 187 surface sediment samples were measured using inductively coupled plasma mass spectrometry. Metals and metalloid in the sediments of the Wuyuer River were greater than the background values of the Songnen Plain, and mean heavy metal concentrations were greater in downstream segments of the river than in upstream segments. Speciation results indicated that Cd was chemically mobile and Cu, Pb, Zn, Cr, and Ni were potentially bioavailable. Mercury and As existed mainly in the residual fraction. Hakanson’s potential risk index indicated that the total potential ecological risk of these elements was moderate in the Wuyuer River. Among the selected metals and metalloid, Hg and Cd were the most potentially toxic and mainly distributed near the cities of Keshan, Yi’an and Fuyü. Because the speciation of Cd in the river sediments is highly bioavailable, the concentrations of Cd should be closely monitored. This research provides managers with information needed to better regulate the environment of the Wuyuer River.     

Ecological risk of heavy metals in sediments of the Luan River source water

Distribution and characteristics of heavy metals enrichment in sediment were surveyed including the bio-available form analyzed for assessment of the Luan River source water quality. The approaches of sediment quality guidelines (SQG), risk assessment code and Hakanson potential ecological risk index were used for the ecological risk assessment. According to SQG, The results show that in animal bodies, Hg at the sampling site of Wuliehexia was 1.39 mg/kg, Cr at Sandaohezi was 152.37 mg/kg and Cu at Hanjiaying was 178.61 mg/kg exceeding the severe effect screening level. There were 90% of sampling sites of Cr and Pb and 50% sites of Cu exceeded the lowest effect screening level. At Boluonuo and Wuliehexia, the exchangeable and carbonate fractions for above 50% of sites were at high risk levels and that for above 30% of sites at Xiahenan and Wulieheshang were also at high risk levels. Other sites were at medium risk level. Compared to soil background values of China, Hg and Cd showed very strong ecological risk, and the seven heavy metals of Hg, Cd, Cu, As, Pb, Cr, Zn at ecological risk levels were in the descending order. The results could give insight into risk assessment of environmental pollution and decision-making for water source security.     

Speciation and distribution characteristics of heavy metals and pollution assessments in the sediments of Nashina Lake,Heilongjiang, China

Sediment core samples from Nashina Lake, Heilongjiang, China were collected using a gravity sampler. The cores were sliced horizontally at 1 cm each to determine the particle size, total concentrations and speciation of Cd, Cr, Cu, Mn, Ni, Pb, and Zn. Total concentrations of heavy metals were extracted using an acid mixture (containing hydro fluoric acid, nitric acid, and sulphuric acid) and analyzed using an inductively coupled plasma spectrometry. A sequential extraction procedure was employed to separate chemical species. Analysis of results indicate that the concentrations of heavy metals in the sediments of Nashina Lake in descending order are Mn, Cr, Zn, Pb, Ni, Cu, and Cd. The ratios of the average concentrations of four heavy metals (e.g.Cr, Cu, Ni, Zn) to their background values were >1; and those of Mn, Cd, and Pb were >1. Moreover, some toxic metals were mainly distributed in bioavailable fractions. For instance, both Cd and Mn were typically found in Acid-extractable species or Fe–Mn oxide species, and thus can be easily remobilized and enter the food chain. Finally, the analysis of geo-accumulation index showed that anthropogenic pollution levels of Cr, Cu, Mn, Ni, Zn were low, but those of Pb and Cd were at the moderate level. As both Pb and Cd are toxic metals, it is highly necessary to prohibit their transformation and accumulation in the sediments.     

Health risk assessment of heavy metals in the water environment of Zhalong Wetland,China

Concentrations of the Cu, Cd, Cr, As, Zn and Ni in water samples from 272 sampling stations in the water environment of Zhalong Wetland, China were studied. Health risk assessment associated with six heavy metals and metalloid was conducted using health risk assessment model from United States Environmental Protection Agency. It can be concluded that the mean concentrations of Cu, Ni, Zn, As, Cd and Cu were 0.19, 0.45, 0.52, 4.9, 0.12 and 0.24 μg L^?1, respectively. The carcinogenic risk of Cr, As and Cd in the discharged area, experimental area, buffer area and core area were lower than the maximum allowance risk level recommended by International Commission on Radiological Protection (ICRP 5.0 × 10^?5 a^?1). The non-carcinogenic risks (Cu, Zn, Ni) was also lower than the maximum allowance levels recommended by ICRP. Though it was lower than the level, it was very approaching to maximum acceptable risk level, need to draw attention to the relevant departments.     

Distribution and risk assessment of heavy metals in the economic fish of the Southern Fujian Province

The distribution and risk assessment of heavy metals (Pb, Cu, Cr, Zn, Cd, As and Hg) in the economic fish of the Southern Fujian Province was acquired. The Cd content was below the detection limit. 53.5% of As and 26.7% of Hg were lightly polluted, but the indices of P_in (Nemero comprehensive pollution index) and MPI (metal pollution index) both indicated no pollution. The indices of EDI (estimated daily intake) and THQ (target hazard quotient) both indicated no non-carcinogenic risk of HMs. The index of R_i (average annual cancer risk) verified no carcinogenic risk for Pb and acceptable risk for As. Furthermore, molecular docking results revealed As may have significant reproductive toxicity to humans. Our findings serve to heighten an awareness of economic fish consumption and provide a reference for marine environmental management and food security in study area.     

Distribution and ecological risk assessment of organochlorine pesticides in sediments from four lakes of Heilongjiang Province,China

There is growing concern for the lake environment because polluted sediments may cause ecotoxicological effects. In the current study, persistent organochlorine compounds (OCPs), including hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and cyclodienes, were analyzed in core sediments taken from Huoshaohei Lake, Xihulu Lake, Wanghua Lake and Keqin Lake, Heilongjiang Province, China. The total OCPs concentrations ranged from 0.92 to 7.09, 0.15 to 9.95, 0.19 to 1.84 and 0.06 to 3.52 ng/g, respectively. The most dominant pollutants were the HCHs, high proportions of γ-HCH isomer indicating the recent input of lindane. The ratios of α-HCH/γ-HCH of four lakes are all lower than that in technical HCH mixtures indicating that there was input of lindane in the past several years, and the mean ratios of (DDE+DDD)/DDTs are all <0.5, suggesting recent release of DDT compounds. Compared with the corresponding ecological environmental quality guidelines from Ingersoll and base on the model of risk based corrective action environmental health risk assessment, the sediments from the four lakes poses a lower potential hazard to human health and the environment but still should be taken into account.     

Distribution characteristics and ecological risk assessment of toxic heavy metals and metalloid in surface water of lakes in Daqing Heilongjiang Province,China

It is necessary to estimate heavy metal concentrations and risk in surface water for understanding the heavy metal contaminations and for sustainable protection of ecosystems and human health. To investigate the anthropogenic contribution of heavy metal accumulation surrounding an industrial city in China, the concentrations of six heavy metals, including mercury (Hg), arsenic (As), chromium (Cr), lead (Pb), copper (Cu), and cadmium (Cd) were examined; from four different regions of Daqing in autumn 2011 and winter 2012. The results showed heavy metals distributed in the industrial area at concentrations relatively higher than those in other three areas, while concentrations in the farming area and the protected area were lower. The heavy metal concentrations of water bodies in all areas, except those for Hg and As, Cu, Pb and Cr were lower than the cutoff values for the Class I water quality that was set as the highest standard to protect the national nature reserves. While Hg and As of lakes in industry region had a higher level than those in the agriculture and landscape water, the lowest allowed. The concentrations of all the heavy metals in winter were higher than in the autumn. Cu had a higher ecological risks level to freshwater organisms. The discharge of urban sewage and industrial wastewater might be a major pollutant source, thus these sources should identified before remediation efforts. Efforts are needed to protect the lakes from pollution and also to reduce environmental health risks. This study and the valuable data will pave the way for future research on these Lakes in Daqing.     

Distribution and ecosystem risk assessment of polycyclic aromatic hydrocarbons in the Luan River,China

The distribution and ecosystem risk of 16 polycyclic aromatic hydrocarbons (PAHs) in the Luan River, China, has been investigated. ∑PAHs levels ranged from 37.3 to 234 ng L⁻¹ in water, from 20.9 to 287 ng g⁻¹ in sediment and from 36.9 to 378 ng g⁻¹ in bank soil, respectively. A method based on toxic equivalency factors (TEFs) and risk quotient (RQ) which can be used to assess the ecosystem risk of ∑PAHs sensitively and accurately was invented and a new ecosystem risk classification of ∑PAHs was suggested. The results indicated that the PAHs in aquatic environment of the Luan River resulted in low ecosystem risk and at S9 the ecosystem risk of PAHs in water was moderate. Low and moderate molecular PAHs presented much more ecosystem risk than high molecular PAHs in the Luan River basin and the mean ecosystem risk in water was higher than that in sediment and bank soil.     

Ecological and health risk assessment of heavy metals in the Hattar industrial estate,Pakistan

Abstract

This study aimed to determine the heavy metals (HMs) contaminations in soil of the Hattar industrial estate (HIE), Haripur, Khyber Pakhtunkhwa. For this purpose, various types of soils were collected in HIE and analyzed for the HMs concentrations. The HMs showed highest contamination levels in wastewater irrigated agriculture soil (WWIAS), followed by waste dump site soil (WDSS), and the lowest in range land soil (RLS). Determined HMs concentrations were used for pollution quantification factors, including contamination factors (CFs), pollution load index (PLI), ecological risk factor (ER), and potential health risk assessment, including chronic or non-cancer and cancer risk levels.     

Prediction and risk assessment of five heavy metals in maize and peanut: A case study of Guangxi,China

To assess the contamination levels and health risk of cadmium (Cd), copper (Cu), mercury (Hg), lead (Pb), and zinc (Zn) to human beings, the concentrations of these heavy metals in soil were surveyed and the concentrations in maize and peanut grains were estimated by models. The geo-accumulation index (I _geo) was calculated, and chronic daily intake (CDI), hazard quotient (HQ) and hazard index (HI) were estimated. Results indicated that the concentrations of Cd, Cu, Hg, Pb, and Zn in the soil samples exceeded the limit set by authorities in China. However, the concentrations in maize and peanut grains were rarely higher than the allowable concentrations suggested by the Ministry of Health of China (MHC). In accordance with geo-accumulation, these heavy metals in soil samples were polluted to different extents. Prediction models were developed to effectively assess the health risk of using TOC, Mn, pH, and CaO to human beings. Therefore, the concentrations of these heavy metals in the grains could be decreased by changing their levels in soil. The CDI, HQ, and HI were estimated by estimating concentrations of Cd, Cu, Pb, and Zn in maize grains, indicating that these metals exhibited a slight health risk to adult residents.     

Evaluation of heavy metals in cosmetic products and their health risk assessment

Heavy metals’ contamination in cosmetic products is a serious threat. Present study was conducted to evaluate the concentrations of heavy metals (HMs) in various brands of cosmetic products with special emphasis on their health risk assessment. Five heavy metals including Cd, Cr, Fe, Ni and Pb were quantified in different brands of lotions, foundations, whitening creams, lipsticks, hair dyes and sunblock creams using atomic absorption spectrometry. Risk to the consumer’s health was determined using systemic exposure dosage (SED), margin of safety (MoS), hazard quotient (HQ), hazard index (HI) and lifetime cancer risk (LCR).On comparative basis, different brands of sunblock creams depicted highest concentration of Ni, Pb and Cr (7.99 ± 0.36, 6.37 ± 0.05 and 0.43 ± 0.01 mg/kg, respectively), whereas lipsticks had elevated levels of Fe at 12.0 ± 1.8 mg/kg, and Cd was maximum in lotions (0.26 ± 0.02 mg/kg). Multivariate analysis revealed strong associations among Cr, Ni and Pb, while Cd and Fe showed disparity in distribution and sources of contamination. MoS, HQ and HI values were within the permissible limit apart from for lotions and sunblock creams, while LCR value was higher than the permissible limit in all cosmetic products except lipsticks. Regular use of these products can cause serious threat to human health, particularly skin cancer on long time exposure. Therefore, continuous monitoring of cosmetic products, particularly with reference to HMs adulteration should be adopted to ensure the human safety and security.     

Health risk assessment of eight heavy metals in nine varieties of edible vegetable oils consumed in China

Eight heavy metals, namely Cu, Zn, Fe, Mn, Cd, Ni, Pb and As, in nine varieties of edible vegetable oils collected from China were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) and graphite furnace atomic absorption spectrometry (GF-AAS) after microwave digestion. The accuracy of procedure was confirmed by certified reference materials (GBW10018 and GBW08551). The relative standard deviations were found below 10%. The concentrations for copper, zinc, iron, manganese, nickel, lead and arsenic were observed in the range of 0.214–0.875, 0.742–2.56, 16.2–45.3, 0.113–0.556, 0.026–0.075, 0.009–0.018 and 0.009–0.019 μg g⁻¹, respectively. Cadmium was found to be 2.64–8.43 μg/kg. In general, iron content was higher than other metals in the investigated edible vegetable oils. Comparing with safety intake levels for these heavy metals recommended by Institute of Medicine of the National Academies (IOM), US Environmental Protection Agency (US EPA) and Joint FAO/WHO Expert Committee on Food Additives (JECFA), the dietary intakes of the eight heavy metals from weekly consumption of 175 g of edible vegetable oils or daily consumption 25 g of edible vegetable oils for a 70 kg individual should pose no risk to human health.     

Risk assessment of heavy metals in honey consumed in Zhejiang province,southeastern China

The levels of copper (Cu), zinc (Zn), cadmium (Cd), lead (Pb), arsenic (As), and mercury (Hg) in eight types of honey collected in China were determined. The average concentrations of the six heavy metals in the honey samples were 46.18, 1329.5, 1.34, 33.98, 13.44, and 1.65 μg kg⁻¹, respectively. All these values were below the maximum allowable contaminant levels in foods (GB2762-2005) and honey (GB14963-2011) in China. The hazard quotients of individual heavy metals and the hazard index of all six heavy metals were far below one, indicating no chronic-toxic risk from these metals for the inhabitants of Zhejiang under the current consumption rates of honey. However, the carcinogenic risk of As for the female inhabitants in Zhejiang exceeded the acceptable level of 10⁻⁴. Therefore, As is the most concerning heavy metal in honey.     

Spatial distribution and ecological risk assessment of metals in sediments of Baiyangdian wetland ecosystem

Although there are many studies of heavy metal contaminations of sediments, attention has seldom been paid to the problem in developing countries. The purpose of this article is to find the distribution and ecological risk of As, Hg, Cr, Cd, Pb, Cu, and Zn in surface sediment of Baiyangdian which is the biggest wetland in Northeast China. We apply three methodologies. The first is literature analysis comparing total concentrations of heavy metals with other water bodies around world. The second is Chinese Environmental Quality Standard for Soils (EQSS), National Environmental Protection Agency of China 1995, and the third is Soil and Aquatic Sediment Guidelines and Standards issued by New York Department of Environmental Conservation (NYSDEC). The results show that compared to other water bodies around the world, the seven heavy metals are low. However, Cd was found in the most polluting level of EQSS near a village and was second grade some distance from it. The village was also the most polluted site of Zn, which was in the second grade. When assessed by NYSDEC, Cu, Cr, and As contaminated the sediment and with moderate impacts on benthic life while Pb, Hg, and Zn were found at tolerable levels throughout Baiyangdian. The centre of Cu and Cr contamination was also near the village. As is the most polluting heavy metals with a major occurrence in the middle of the wetland. There were no heavy metals creating severe disturbance to the benthic communities. Based on the assessment, this article proposes different options for more sustainable management.     

Bio-accumulation and health risk assessment of heavy metals in different edible fish species from Hurghada City,Red Sea,Egypt

BackgroundHeavy metal contamination has become a serious issue in this century especially detected in fish organs. Due to the presence of radioactive compounds in agricultural and sewage effluent, which destroys aquatic ecosystems, threatening human livelihoods. Health hazards associated with low and high consumption consumers assessed in five commercial fish species collected from Hurghada City, Egypt, during winter and summer, 2020. Atomic absorption spectrophotometer technique used for determination heavy meals in different organs and expressed as μg/g wet weight.ResultsHeavy metal concentrations in muscle ranged between:(0.054–0.109), (0.260–1.043), (0.264–0.897), (5.895–11.898), (0.381–0.970), (13.582–29.133) and (0.332–0.589) µg/g for Cd, Pb, Mn, Zn, Cu, Fe and Ni respectively, which were lower than those of gills and liver. These concentrations were within WHO, FAO/WHO, and EU standards. Consumption of edible species was lower than the (TDIs) established by the (JECFA) and Egyptian Standards. Even though THQ and TTHQ values were < 1 while, in children with highly consumer were> 1.ConclusionThis study concluded that intake of Red Sea fish is safe for human health. It is critical for consumers to be aware of the consequences of excessive fish consumption, particularly children with highly consumer, which represent possible health risks.     

Non-carcinogenic risk assessment induced by heavy metals content of the bottled water in Iran

Recently, the exposure to heavy metals from bottled waters raised huge concerns. In this context, for the first time the risk of non-carcinogenic exposure by the heavy metals in Iranian drinking water was assessed. Therefore, by using the obtained data in our previous published study, the target hazard quotient (THQ) and total target hazard quotient (TTHQ) by considering to the sexuality of consumers were calculated. THQ in females were determined as significantly higher (p??Pb?>?Hg?>?Cd?>?Cu, respectively. The minimum and maximum of THQ for the males were observed in age groups of?+65 and 1–3?years, respectively. The minimum and maximum of THQ for females were noted in age groups of 11–14 and 1–3?years, respectively. Since TTHQ for all ages were less than 1 (p?相似文献   

Concentrations and risk assessment of polychlorinated biphenyls and polybrominated diphenyl ethers in surface sediments from the East Lake,China

Ecotoxicology - The concentrations of polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) in surface sediment samples collected from the East Lake, China in winter 2012 and...