Health risk assessment of some heavy metals in urban community garden soils of Baghdad City,Iraq

The objective of this study is the evaluation of health risk of heavy metals in soils of urban community gardens of Baghdad City in Iraq. The soil samples were collected from 14 community gardens and analyzed for Cd, Cr, Cu, Ni, Pb and Zn. The non-carcinogenic hazard index (HI) and carcinogenic risk index (RI) were utilized to evaluate human health risk of heavy metals. The health hazard evaluation showed that there is no non-carcinogenic hazard in light of the fact that the HI values were beneath the threshold value (HI < 1). The HI for children and adults has a descending order of Cd < Cr < Cu < Ni < Pb < Zn. The carcinogenic RI values for Cd, Cr and Ni were over the unacceptable threshold value (RI < 1 × 10^?4), demonstrating that there is a serious carcinogenic risk for children and adults in the study area. The carcinogenic RI for children and adults has a descending order of Cr < Cd < Ni. These findings give environment administrators and leaders data on whether therapeutic activities are required to decrease exposure.     

Health Risk Assessment of Heavy Metals in Urban Soil of Karachi,Pakistan

The potential health risk due to lifetime exposure to copper, lead, chromium, zinc, and iron in urban soil of Karachi, Pakistan, was evaluated. Mean concentrations of Cu, Pb, Cr, Zn, and Fe in topsoil samples were 33.3 ± 12.8, 42.1 ± 55.8, 9.6 ± 4.2, 99.5 ± 37.3, and 908.4 ± 57.8 mg kg^?1, respectively. A U.S. Environmental Protection Agency model was adopted for the carcinogenic and non-carcinogenic risk assessment from different exposure pathways. Risk assessment indicated that the overall results for the carcinogenic risk were insignificant. However, the carcinogenic risk from Pb due to oral ingestion of soil exceeded the value of 1 × 10^?6, in some areas of the city. It indicates that the exposure to Pb-contaminated soil may cause adverse health effects in humans, especially in children. The Hazard Quotient (HQ) for different metals through ingestion and dermal pathways was also found to be less than 1. The combined Hazard Index (HI) for children through different routes of exposure was 8.9 times greater than for adults. It indicates that the children are more susceptible to non-carcinogenic health effects of trace metals compared to adults. Particularly, non-carcinogenic risk of Pb to children via oral ingestion needs special attention.     

Heavy metals in urban and peri-urban soils of a heavily-populated and industrialized city: Assessment of ecological risks and human health repercussions

Abstract

Increasing levels of heavy metals in soil have become a serious concern for human health because they can be easily transferred into the human body through contaminated food web. It is imperative to evaluate pollution levels, origin and ecological risks of heavy metals. The geoaccumaualtion (Igeo), contamination factor (CF), pollution load index (PLI) and human health risk were estimated to determine the soil pollution in Faisalabad, a heavily-populated and industrialized city of Pakistan. The maximum CF (1.58) and PLI (1.22) values were estimated for Cd and Pb, respectively, and maximum Igeo (?0.19) value was observed for Cd. Correlation analysis and principal component analysis suggested that common industrial sources for Cd and Pb were identified in the study sites. It clearly indicates that the significant levels of heavy metals pollution arise from local industries, busy commercial centers and heavy traffic load in the last few decades in heavily-populated and industrialized city. Further, soil heavy metals concentration were used to evaluate the human health risk such as chronic or non-carcinogenic including hazard indexes HIexP (ingestion, inhalation and dermal and carcinogenic) and cancer risk (CR). The HIexP values of Pb (10.30) and Cd (4.56) were found above the permissible limit (HI = 1) for children. The CR due to carcinogenic metals (Co, Cr and Cd) are within the safe limit (1E-06 to 1E-04). However, CR was comparatively higher in adults as compared to children. The results from the current investigation can help to develop a sustainable strategy in the study region to minimize the entry of heavy metals in food chain through source identification and pollution abatement techniques.     

Heavy metals contamination in shallow groundwater of a coal-mining district and a probabilistic assessment of its human health risk

To manage public health and make better use of groundwater resources, the concentration characteristics and a health risk assessment of eight heavy metals in shallow groundwater were studied. Besides this, this paper introduced triangular fuzzy numbers into the USEPA health risk assessment model to assess the health risk posed to local children and adults through different exposure pathways. The results showed that Mn levels exceeded the WHO’s guideline values of 100?µg/L with the proportion of 27.98% and Sr were over the health reference level (HRL) of 1500?µg/L with the proportion of 56.25%, while other heavy metals were below the corresponding standard. The results of the HRA showed that the non-carcinogenic risks from Sr and Mn in the district were relatively higher, while those from the remaining six heavy metals were relatively lower. All hazard index (HI) values did not exceed the safety level of 1 for either age group. The average carcinogenic risk from Cr was slightly higher than the acceptable level of 1?×?10^?6 for adults. Sensitivity analyses conducted using Monte Carlo simulation indicated that Sr and Cr concentrations were the most influential variables contributing to the non-carcinogenic and carcinogenic risk values, respectively, while body weight had a minor contribution.     

Source identification and risk assessment of heavy metals in road dust of steel industrial city (Anshan), Liaoning,Northeast China

Abstract

The purpose of the study was to acquire the source and evaluate the risk posed by heavy metals in road dust of steel industrial city (Anshan), Liaoning, Northeast China. Potential ecological risk index (RI), pollution index (PI) and geo-accumulation index (Igeo) were applied to evaluate the heavy metal pollution level, and the carcinogenic risk (RI) and hazard index (HI) were calculated to estimate the human health risk. The geographic information system maps clearly reveal the hot spots of heavy metal spatial distribution. Principle component analysis (PCA) and cluster analysis (CA) classified heavy metals into three groups. The metal Zn and Pb originate from the traffic emission, while Cd, Cr, Fe, Mn, Ni and Sb primarily come from industrial activities. These two pathways were the major source of heavy metals pollution by positive matrix factorization (PMF). The Igeo and PI values of heavy metals were decreased in the following order: Cd?>?Sb?>?Zn?>?Fe?>?Pb?>?Cu?>?Cr?>?Sn?>?Mn?>?Ni. The RI index showed the heavy metals were moderate to very high potential ecological risk. The HI values for children and adults presented a decreasing order of Cr?>?Pb?>?Ni?>?Cu?>?Cd?>?Zn. The HI also predicted a possibility of non-carcinogenic risk for children living in urban areas in comparison with adults.     

Hazardous metals levels in groundwater from Gokana,Rivers State,Nigeria: Non-cancer and cancer health risk assessment

This study investigated heavy metals concentration in groundwater in six coastal communities in Gokana, Rivers State, namely, Gbe, K-Dere, B-Dere, Mogho, Kpor and Bodo City and the human health risk posed to the local populace via ingestion and dermal contact using non-carcinogenic and carcinogenic health risk assessment. The mean values of the heavy metals ranged between 0.02–0.86, 0.16–0.19, 0.03–0.10, 0.02–0.03 and 0.01–0.17 for Mn, Ni, Pb, Cd and Cr, respectively. The heavy metals were above the drinking water quality recommended limits in all the study sites. Estimations of average daily dose (ADD) and dermal absorbed dose (DAD) health risk indicates that Mn, Ni and Pb posed human health risk via ingestion contact pathway. However, hazard index (HI) values of Cd and Cr for ingestion pathway were >1.0 and the estimated Lifetime of Carcinogenic Risks (LTCR) for Ni, Cd and Cr exceeded the predicted lifetime risk for carcinogens of 10^?6 from ingestion pathway. Furthermore, there were more appreciable risk from Ni and Cr in the study sites as LTCR value in most sites were >10^?4_. This study indicates possible non-carcinogenic and carcinogenic human health hazard from groundwater consumption in Gokana via oral ingestion.     

Heavy metal contamination and health risk assessment in drinking water of Sistan and Baluchistan,Southeastern Iran

Access to safe and clean drinking water is an essential element of healthy life also known as the primary human needs. The present study was conducted to investigate heavy metal (HM) concentrations of drinking water. Excess health risk of HM (Cr, Pb, and Cd) intake is related to the drinking water consumption in local population. HMs concentrations were analyzed by using graphite furnace atomic absorption spectrometer and were compared with permissible limits regulated by country and World Health Organization (WHO). The hazard quotient (HQ) and Excess Lifetime Cancer Risk (ELCR) were determined to show the carcinogenic and non-carcinogenic effects of HMs, respectively. HQs were found in the order of Pb > Cd > Cr and subsequently HI index was also estimated for all HM in two age groups (children and adults). The comparisons indicate no possibility of non-carcinogenic effects to the local population. The values for ELCR were found in the order of Cr > Cd > Pb. The ELCR index was found above acceptable risk levels for chromium and cadmium in both children and adults groups. Furthermore, intermetal correlation results revealed that heavy metals have common sources resulting from geogenic and anthropogenic activities and these are major sources of water contamination in Sistan and Baluchestan province.     

Heavy metals contamination and human health risk assessment in soils of an industrial area,Bandar Abbas – South Central Iran

The purpose of this study was to determine the contamination level, distribution, health risk and potential sources of Cr, Cd, Pb, Zn, Cu, Ni and As in 66 topsoil samples from industrial areas in Bandar Abbas County. The geoaccumulation index, pollution index and pollution load index were calculated to assess the pollution level in the industrial soils. The hazard index and carcinogenic risk were used to assess human health risk of heavy metals. Results showed that the contamination levels of heavy metals were in the descending order of Cu> Cd> Pb> Zn> As> Ni> Cr. Moreover, based on principal component analysis, Cd, Zn, Cu, and Pb originated mainly from anthropogenic sources, including power plants, oil and gas refinery, steel and zinc production factories and municipal waste landfills. For non-carcinogenic effects, hazard index of studied metals decreased in the order of Cr> As> Cd> Pb> Ni > Cu> Zn. Arsenic, chromium and cadmium were regarded as the priority pollutants. Carcinogenic risks due to Cd and As in suburban soils were within tolerable risk to human health; however, children faced more health risk in their daily life than adults via their unconscious ingestion and dermal contact pathway.     

A human health risk assessment of heavy metals in agricultural soils of Yanqi Basin,Silk Road Economic Belt,China

A total of 195 farmland soil samples were collected in Yanqi Basin, Xinjiang, northwest China, and the concentrations of As, Cd, Cr, Cu, Ni, Pb, and Zn were analyzed for their concentrations and pollution levels using the Nemerow comprehensive index. The health risk assessment model introduced by USEPA was utilized to evaluate the human health risks of heavy metals. Results indicated that the average concentrations of these seven metals were lower than the allowed soil environmental quality standards of China, while the average concentrations of Cd, Cr, Ni, Pb and Zn exceeded the background values of irrigation soils in Xinjiang. The average contamination factor (CF) for Pb indicated the heavy pollution, whereas the CF for Cd, Zn, Ni, Cu and Cr indicated the moderate pollution. The average PLI of heavy metals indicated the low pollution. The non-carcinogenic hazard index were below the threshold values, and the total carcinogenic risks due to As and Cr were within the acceptable range for both children and adults. As and Pb were the main non-carcinogenic factors, while As was the main carcinogenic factor in the study area. Special attentions should be paid to these priority control metals in order to target the lowest threats to human health.     

Heavy Metal Contamination in Urban Surface Soil of Klang District (Malaysia)

This study aimed to determine bioavailability of heavy metal concentrations (Al, Fe, Zn, Cu, Co, Cd, Pb and Cr) in 76 urban surface soil samples of Klang district (Malaysia). This study also aimed to determine health risks posed by bioavailability of heavy metals in urban soil on adults and children. For bioavailability of heavy metal concentrations, a physiologically bioavailability extraction test in vitro digestion model was used. Mean values of bioavailability heavy metal concentrations for this study were found to be the highest in Al (25.44 mg/kg) and lowest in Cr (0.10 mg/kg). Results of Spearman correlation coefficient (r) values showed significant correlations were observed for Al-Fe (r = 0.681), Cd-Co (r = 0.495), Cu-Zn (r = 0.232), Fe-Pb (r = 0.260), Fe-Zn (r = 0.239). For cluster analysis, output showed that these heavy metals could be classified into four clusters: Cluster 1 consisted of Cd, Cr, Co, and Pb; Cluster 2 consisted of Zn and Cu; Cluster 3 consisted of Fe; and Cluster 4 consisted of Al. For Clusters 1 and 2, anthropogenic sources were believed to be the sources, while for Clusters 3 and 4 the heavy metals originated from natural sources. Health risks were determined in adults and children through health risk assessment. For adults, Hazard Quotient (HQ) value was <1, indicating no non-carcinogenic risk, while for children, the HQ value was >1, indicating a non-carcinogenic risk. Meanwhile, for carcinogenic risk, heavy metal contamination in the Klang district might not pose a carcinogenic risk to adults while it may pose a carcinogenic risk to children because TR values in this study were >1.0E-04 for children. Output has identified the general health risk in the Klang district. Moreover, this study's findings will contribute to fill in the gap of knowledge on heavy metals' impacts on human health and urban development in the Klang District.     

Assessment of potential health risk of heavy metals in soils from a rapidly developing region of China

Soil heavy metal contamination is a major environmental concern, and health risk associated with heavy metals is not fully explored. A combination of spatial analysis and Monte Carlo simulation was successfully used to identify the possible sources and health risk of cadmium (Cd), arsenic (As), mercury (Hg), lead (Pb), chromium (Cr), and copper (Cu) in soils collected from a rapidly developing region of China. It was found that mean concentrations of Cd (0.17 mg/kg ), As (8.74 mg/kg ), Hg (0.15 mg/kg ), Pb (27.28 mg/kg ), and Cu (33.32 mg/kg ) were greater than the soil background values. Accumulation and spatial variability of heavy metals were significantly affected by anthropogenic activities and soil properties. The risk assessment indicated that non-carcinogenic risk was not significant. However, 95% of the total cumulative carcinogenic risk of children was greater than 1E-05, implying high potential carcinogenic risk with As and Pb representing the major contributors. Ingestion of heavy metals in the soils was the main exposure pathway compared with the inhalation and the dermal exposure. Concentration of heavy metals in the soils, particulate emission factor, and dermal exposure ratio were the major parameters affecting health risk. This study highlights the importance of assessment of soil direct exposure health risk in studying heavy metal exposures.     

Determination of the Heavy Metal Levels in Panax notoginseng and the Implications for Human Health Risk Assessment

ABSTRACT

High levels of heavy metals in Panax notoginseng (Sanchi), a valued traditional Chinese medicine, have drawn increasing concern regarding the safe usage of Sanchi preparations. Here, we measured the concentrations of six heavy metals in Sanchi samples from 20 major plantations, investigated the pharmaceutical processes and usages of Sanchi preparations, and assessed the associated potential health risks to consumers. The average concentrations of chromium (Cr), copper (Cu), nickel (Ni), zinc (Zn), lead (Pb), and arsenic (As) in the Sanchi samples were 2.7, 3.7, 6.2, 22.1, 2.0, and 1.4 mg/kg, respectively. The hazard quotients (HQs) for these six single metals and the hazard index (HI) of these metals’ combination were all far less than 1, indicating the absence of a non-carcinogenic health hazard to consumers. The carcinogenic risk of As was 2.1 × 10^?6, which is higher than the allowable level suggested by the U.S. Environmental Protection Agency but less than the level suggested by the World Health Organization (WHO). The probabilities of consumers’ exposure due to daily medicine consumption exceeding the allowable daily intakes from medicine (ADIs_drug, 1% of the ADI) suggested by the WHO were 0.0%, 0.1%, 0.1%, 0.0%, 1.6%, and 27.3% for Cr, Ni, Cu, Zn, Pb, and As, respectively.     

Assessment of heavy metal pollution and human health risk in urban soils of a coal mining city in East China

The aims of this study were to determine the concentrations, distribution, potential ecological risk (PER), and human health risk (Risk) of heavy metals in urban soils from a coal mining city in China. A total of 36 topsoil samples from Huainan city, Anhui, East China, were collected and analyzed for As, Hg, Pb, Cd, Cr, and Cu. The PER was calculated to assess the pollution level. The hazard index (HI) and carcinogenic risk were used to assess the human health risk of heavy metals in the study area. The average concentration of As, Hg, Pb, Cd, Cr, and Cu were 12.54, 0.21, 24.21, 0.19, 49.39, and 21.74 mg kg^?1, respectively. The correlations between heavy metals indicated that Cu, Cr, Cd, and Pb mainly originated from automobile exhaust emissions, coal gangue, fly ash, and industrial wastewater, and that As and Hg mainly came from coal combustion exhaust. The PER index values of heavy metals decreased in the following order: Hg > Cd > As> Cu > Pb > Cr. The HI and Risk values indicated that the noncarcinogenic and carcinogenic risks of selected metals in the urban soil were both below the threshold values.     

Heavy metal contamination and health risks of indoor dust around Xinqiao Mining Area,Tongling, China

Abstract

In this study, the concentrations and health risks of heavy metals (Cu, Pb, Zn, Ni, Co, Cd, and Cr) in indoor dust are investigated in the vicinity of the Xinqiao mining area, Tongling, China. Results indicate that heavy metals except Co were clearly enriched in indoor dust. Especially Cd was extremely enriched, followed by Zn, Cu, and Pb. However, no significant regional differences (p?>?0.05) were found in other elemental contents aside from Cu. Statistical analysis revealed that metal elements except Co were presumed to originate primarily from mining activities. Health risk assessment indicated that the hazard quotients and hazard indices of all studied metal elements were less than 1 and thus posed no potential noncancer health risks to adults and children. Moreover, the cancer risks of Ni, Cr, Cd, and Co were within acceptable ranges, implying no cancer risk to local residents; however, the noncarcinogenic risk of Pb and the carcinogenic risk of Cr and Cd warrant close attention.     

Health Risks of Metals in Soil,Water, and Major Food Crops in Hamedan Province,Iran

Food, drinking water, soil, and air are the main routes of exposure to trace metals, thus the assessment of the risks posed to humans by these elements is important. Wheat, potatoes, and maize are very important parts of the Iranian diet. The objectives of this study were to estimate the non-carcinogenic and carcinogenic health risks of Hg, Pb, Cd, Cr, Se, As, and Ni to adults and children via soil, water, and major food crops consumed in Hamedan Province, northwest Iran, using the total non-cancer hazard quotient (THQ) and cancer risk assessment estimates. Total non-cancer hazard of Ni and Hg, were greater than 1, and total cancer risk of As and Pb was greater than 1 × 10^?6. Food consumption was identified as the major route of human exposure to metals, and consuming foodstuff threatens the health of the studied population. In Hamedan Province, consumption of wheat is the main source of intake of metals from foodstuff for adults, and in children, the soil ingestion route is also important.     

Health Risk Assessment of Metals in Surface Water from Freshwater Source Lakes,Pakistan

This study investigated the concentrations of selected metals (Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Pb, Sr, and Zn) in freshwater source lakes in Pakistan and assessed the preliminary health risks associated with them. Water samples were collected from Khanpur and Simly Lakes and analyzed for the metals using flame atomic absorption spectrophotometry. Major contributions were noted for Ca, K, Mg, and K; however, the measured levels of Cd, Co, Cr, and Pb were many times higher than the permissible national/international guideline values. The risk characterization revealed that hazard quotient (HQ_ing) and hazard index (HI_ing) values exceeded the acceptable limit unity, indicating non-carcinogenic risk to the recipients via oral intake of contaminated water. The carcinogenic risk (CR_ing) via ingestion route for Cd, Cr, and Pb was found much greater than the acceptable limit (10^–6). Overall, Cd, Co, Cr, and Pb were the major contributors to potential adverse health risk to the inhabitants. Multivariate analysis demonstrated anthropogenic intrusions of the metals in both lakes. The study clearly indicated that there was gross contamination of water in both lakes, so special attention should be paid to manage the pollution sources of metals.     

Pollution and health risk assessment of heavy metals in urban soil in China

The pollution and potential health risk due to lifetime exposure to heavy metals in urban soil of China were evaluated, based on the urban soil samples collected from published papers from 2005 to 2014. The contamination levels were in the order of Cd > Hg > Cu > Zn > Pb >As > Ni > Cr, and Hg and Cd fell into the category of “moderately contaminated” to “heavily contaminated.” The non-carcinogenic risk for different populations varied greatly, among which children faced high risk, and then the adult female and adult male followed. The hazard index (non-carcinogenic risk) higher than 1.00 occurred in Shanghai, Gansu, Qinghai, Hunan, and Anhui, whereas most of those in northern and western China had low risks. For the carcinogenic risk, Anhui and Ningxia provinces had urban soils exceeding the safe reference (1 × 10^?6–1 × 10^?4). Qinghai and Gansu had high carcinogenic risks since their risk indexes were much closer to the reference, and the others were in low risk.     

Widespread environmental contamination in agricultural soils and human health risk at the vicinity of an oil refinery site

In this research, carcinogenic and non-carcinogenic human health risks due to polycyclic aromatic hydrocarbons (PAHs) were investigated via three exposure pathways: accidental ingestion of soil, dermal contact of soils, and contaminated vegetable ingestion. To determine the contaminant concentrations in soil, samples were collected from areas adjacent to the Tehran oil refinery, located in Shahr-e-Ray city, Iran. Analyses of the samples indicated that the average of PAHs concentration in the soil samples were greater than clean-up level guidelines. Cancer risk of contaminants due to ingestion of cultivated vegetables that are sold in Tehran markets was significant in comparison with other exposure pathways. Moreover, the total cancer risk for 5th percentile, 95 upper confidence limit, and 95th percentile concentration of contaminants were 5.69E-04, 8.78E-02, and 2.13E-01, classifying the site as having a significant cancer risk potential. Furthermore, non-carcinogenic health risk analyses for the contaminants demonstrated hazard index of less than 1. Remediation of the soils is highly recommended to eliminate the potential cancer risks and prevent the contamination of the food chain for approximately 10 million Tehran residents.     

Human Health Risk Assessment for Environmental Exposure to Metals in the Catalan Stretch of the Ebro River,Spain

The aim of this study was to investigate the environmental impact and the human health risks associated with metals exposure in the Catalan stretch of the Ebro River, Spain. The concentrations of the following elements were determined in soils and tap water: As, Cd, Cr, Cu, Hg, Mn, Ni, and Pb. Carcinogenic and non-carcinogenic risks were separately assessed for adults and children. Relatively low metal concentrations in tap water were found. It indicates that water intake is not a relevant source of metals for human health impact in the area under evaluation. In turn, the levels of metals in soils were similar or less than those found in a number of recent worldwide surveys. The presence of industrial facilities located upstream the Ebro River, including a chloralkali plant, should not mean additional non-carcinogenic risks for the population living in the area. The results of the current study allow us to establish that the concentrations of most carcinogenic elements (with the exception of As) should not mean potential health risks for the local population. However, because of the relatively high levels of geological origin found for As, a continued monitoring of these elements would be desirable.     

Toxic metal ion in seafood: Meta-analysis of human carcinogenic and non-carcinogenic threat assessment,a geomedical study from Dhamra and Puri,Odisha

The investigation revealed the adverse health threats on human beings from toxic metals via ingestion of seafood from two contaminated sites in Odisha. Bioaccumulation through food chain was presented as tissue metal concentrations. The non-carcinogenic and carcinogenic health hazards were estimated by Target Hazard Quotient (THQ) and Target Cancer Risk (TCR) following USEPA referred safe metal intake limit. THQ of Metals like Mn, Ni, Cd, Pb in both sites showed >1, indicating a severe non carcinogenic health threat to humans from the investigated metals. THQ of Cu, Zn, Fe, Cr and Hg showed < 1, implying the least possible deleterious health effects. Cr was the most significant carcinogenic pollutant in both sites. The marine fish consumption of Dhamra site might cause extra 7 cases of cancer per 10000 populations due to higher Cr level (cancer risk 6.7 × 10^?3). Carcinogenic risk of Ni and Pb were below the tolerable range of 10E-4. The presence of Cd in sea foods elevated cancer risks in both sites. The metal pollution index (MPI) indicated, the highest toxic metal bio accumulation was contributed by Arius arius species. Ilisha megaloptera and Lates calcarifer from Dhamra and Puri showed highest hazard index (HI) suggesting unaccountable non-carcinogenic health threat.