Probabilistic Human Health Risk Assessment Research Articles

Concentrations of polycyclic aromatic hydrocarbons in samples of soil, feed and food collected in the Niger Delta region, Nigeria: A probabilistic human health risk assessment

Polycyclic aromatic hydrocarbons (PAHs) are widely distributed compounds with two or more fused aromatic ring, being some of them classified as carcinogenic. In the present study, the concentrations of 16 PAHs and the sum of them (∑PAHs) were determined in samples of food, feed, plant and soil collected in six different heavily polluted areas (Choba, Khana, Trans Amadi, Eleme, Uyo and Yenagoa) of the Niger Delta Region (Nigeria). Principal component analysis (PCA) was then used to identify groups of variables (PAHs) and groups of samples that were the best in rendering the environmental pollution in that Region of Nigeria. In addition, PAHs food consumption and the derived carcinogenic risks were assessed in a probabilistic way. The highest ∑PAHs (mg/kg) were: 16.7 in cow meat, 8.06 in goat meat, 25.4 in chicken meat, 7.72 in fish, 28.70 in fish feed, 15.3 in chicken feed, 8.42 in plant, and 8.80 in soil. In most of the Nigerian areas, cooked cow meat, chicken and chicken feed presented the highest impact regarding PAHs contamination. The highest intake of PAHs was through meat consumption, with a very high and unassumable carcinogenic risk, which is quite above 10−5 for some PAHs, including benzo [a]pyrene. The results of the present survey highlight the importance of reducing PAHs content in food, specially in meat, in the Niger Delta region.

Evaluating the geochemistry of groundwater contamination with iron and manganese and probabilistic human health risk assessment in endemic areas of the world’s largest River Island, India

Iron (Fe) and manganese (Mn) are harmful for human health, if present in a higher concentration, particularly in groundwater. The results of the study revealed that the concentration of Fe and Mn exceeded the WHO guideline for safe drinking water in 88 % and 74 % of groundwater samples, respectively. The non-carcinogenic health risk as assessed through computation of hazard quotient (HQ) due to intake of Fe and Mn contaminated groundwater was found much higher for children and adults. The values of HQ were recorded up to 1.96 for children and 1.52 for adult in case of Fe; and up to 2.13 for children and 1.61 for adult associated with Mn. On the basis of occurrence and spatial distribution of Fe and Mn in groundwater, the study area was delineated under high, elevated and low risk zone for priority attention.

Probabilistic Human Health Risk Assessment of Fe, As and Mn in the Groundwater of Dhamrai Upazila, Dhaka, Bangladesh

In Bangladesh, groundwater is the most important source of potable water. This study aims to investigate the amount of Fe, Mn and As in groundwater and to assess the health risks through oral ingestion of these trace metals. Groundwater samples were collected from 20 sample sites throughout the Baishakanda union, Dhamrai upazila for source appointment and risk assessment studies. The concentrations of Fe, Mn, and As were measured using an atomic absorption spectrophotometer. Mean concentration of trace metal level in respectively descending order as Fe>Mn>As. The study found an average concentration of Fe (1.8 mg/L), Mn (0.74mg/L), and As (0.038 mg/L) in the groundwater sample where the mean value of Fe and Mn exceeds the DoE, WHO, and USEPA standards limit. On the other hand, the mean concentration value of As exceeds the WHO and USEPA standards limit. The non-carcinogenic human health risk was calculated by justifying HQ (Hazard Quotient) and HI (Hazard Index).A child (11.4056) is more vulnerable to non-carcinogenic human health risk than an adult (5.3769). Furthermore, As pollution in groundwater samples was found to pose a high carcinogenic risk, with children (3.84×10-3) being more vulnerable to carcinogenic risk than adults (1.81×10-3).The research area's groundwater was with a significant level of non-carcinogenic as well as cancer-risk (As) susceptibility in the local population.

Deterministic and probabilistic human health risk assessment approach of exposure to heavy metals in drinking water sources: A case study of a semi-arid region in the west of Iran.

In the current study, the concentration of heavy metals (Ba, Mn, Pb, and Cd) in drinking water resources of 328 villages in Hamadan Province were measured using ICP-OES apparatus during two dry (September 2018) and wet (April 2019) seasons. The assessment of the non-carcinogenic risk of selected heavy metals was conducted based on the recommendations of the USEPA. Also, sensitivity analysis and uncertainty of the effective variables were performed using Monte-Carlo simulations. Based on the results, Mn level in drinking water samples ranged 0.08-25.63μg/L and 0.08-20.03μg/L in dry and wet seasons, respectively. Similarly, Ba levels in water samples ranged 0.15-70.13μg/L and 0.84-65μg/L. Also, Cd and Pb concentrations in all sampling sites were below the limits of detection (LOD) of the ICP-OES apparatus. The hazard index (HI) values for adult and children were 2.17 × 10-3 and 3.29 × 10-3, respectively, which show a lack of non-carcinogenic risk for the examined heavy metals (Mn and Ba) to the local inhabitants. The results of the sensitivity analyses for adults and children revealed that two variables including metal concentration and ingestion rate of drinking water (IR) had the highest positive effects on the non-carcinogenic risk estimates. It was also found that there was no significant non-carcinogenic risk for the local residents in the studied area due to drinking water consumption.

Ecological and probabilistic human health risk assessment of heavy metal(loid)s in river sediments affected by mining activities in Ecuador.

Gold mining is a significant source of metal(loid)s released into the environment. It is an issue of concern due to the potential adverse health effects associated with exposure to toxic elements. This study aimed to assess the ecological and human health risk caused by heavy metal(loid)s exposure in river sediments in Ponce Enríquez, one of the most important mining sites in Ecuador. Concentrations of As, Cd, Cu, Pb, and Zn were evaluated in 172 sediment samples to determine the Potential ecological risk (RI) and the carcinogenic (CR) and non-carcinogenic risk (HQ). The human exposure to polluted sediments during recreational activities was computed using Bayesian probabilistic models. Residents were randomly surveyed to adjust the risk models to the specific population data. More than 68% of the sampling stations pose a severe As and Cd ecological risk index ([Formula: see text] > 320). Likewise, residents exposed to river sediments showed a non-acceptable carcinogenic risk by incidental ingestion, being As the primary contributor to overall cancer in both children and adults receptors. Moreover, non-carcinogenic risk through the incidental ingestion of sediments was above the safe limit for children. This is the first study conducted in a mining region in Ecuador that reveals the severe levels of ecological and human health risk to which the population is exposed. These results can be applied as a baseline to develop public health strategies to monitor and reduce the health hazards of the residents of mining communities.

Simultaneous determination of multiple pesticide residues in Iranian saffron: A probabilistic health risk assessment

Saffron is a strategic agricultural product having extensive flavoring applications in Asia. Although utilization of pesticides for its cultivation is limited, there is a possible risk of contamination in this prominent spice. Herein, 88 pesticides were analyzed in 34 fsamples collected from the most crucial saffron-rich region of the country using a miniaturized QuEChERS approach and ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Results indicated that LOQs and LDR were within the ranges of 5–50 and 5−1000 μg L−1 (5.49–54.9 and 5.49−1099 μg Kg−1), respectively. Considering LOQ values, 3.4 % out of 34 samples were contaminated by at least one pesticide. The highest mean values related to carbendazim and iprodione were obtained to be 10.6 and 8.79 μg Kg−1, respectively. However, only eight samples exhibited pesticide residues higher than the limits specified by European Union. Furthermore, probabilistic human health risk assessment of pesticides was investigated using a Hazard Quotient (HQ) method in Monte Carlo (MC) algorithm. Total Hazard Quotient (THQ) values according to the consumption of saffron in adults and children were calculated as 2.5E-5 and 1.2E-4, respectively. Consequently, the applied health risk assessment on Iranian saffron samples revealed that HQ for adults and children populations might not pose health hazards. Most Iranian saffron samples are safe; their pesticide residue levels are below the EU MRLs, and the observed mean values were much lower than MRLs.

Deterministic and probabilistic health risk assessment for exposure to non-steroidal anti-inflammatory drugs in an Indian river.

This study presents deterministic and probabilistic human health risk assessment using Monte Carlo simulations on exposure to an Indian river, Kaveri, which has been contaminated by non-steroidal anti-inflammatory drugs (NSAIDs). The NSAIDs of concern are naproxen, ibuprofen, aspirin, ketoprofen, and diclofenac. We have considered three exposure scenarios (water ingestion, dermal exposure, and fish ingestion) for four different age groups (0-5, 6-10, 11-18, and 19-70 years). Deterministic risk assessment revealed teenagers to be the most sensitive receptors and water ingestion to be the most crucial pathway contributing to maximum health risk (79 to 86%). Based on the results of Monte Carlo simulations, it was found that the probability of exceeding the deterministic mean risks ranged from 17 to 39% for different exposure routes. High end risk estimates such as 95th percentiles and maximum values of HQ for the entire population did not exceed the USEPA allowable risk. This implies that the NSAIDs at the detected concentrations in the Kaveri river may not pose adverse health effects even in the worst-case scenario. Among the five NSAIDs, diclofenac was found to be the major contributor for health risk. Moreover, the concentration of diclofenac was just one order less than the estimated site-specific threshold concentrations. From sensitivity analysis, the most and the least impactful parameters were found to be water ingestion rate and fish ingestion rate respectively.

Drinking water quality assessment in distribution networks: A water footprint approach

Reliable water quality monitoring and assessment can help to minimize the risk of water quality failures (WQFs) in water distribution networks (WDNs). Indexing-based water quality assessment approaches classify water quality based on contaminant concentrations. However, the resultant indices do not provide any information on trade-offs between water quality and quantity. The need to preserve the earth's natural resources has drawn attention to the use of footprint approaches to assess water quality. This paper uses a water footprint concept to develop a grey water footprint (GWF)-based framework for water quality assessment. A probabilistic human health risk assessment (HHRA) is also incorporated in the GWF approach to address the uncertainties. The proposed framework was implemented by considering the disinfection by-products (DBPs) in WDNs as a case study, and the results were compared with those generated using the Canadian Water Quality Index (CWQI) approach. Six drinking water quality management strategies (DWQMSs) were evaluated. The results from both approaches were correlated, indicating GWF as an alternative to CWQI. The assessment results showed that DWQMSs having groundwater as a source deliver better water quality in terms of DBPs occurrence compared to those using a surface water source. The GWF approach helps categorize water quality by estimating the theoretical volume of fresh water required to dilute the contaminant concentrations to below threshold levels. Water stakeholders can apply this framework considering any contaminants to drinking water quality using a quantitative water footprint scale and develop a trade-off between water quality and quantity management.

Mercury in skin-care products in India and consumer exposure risks

We report concentrations of mercury in skin-care products in India and the associated health risks. Mercury concentrations were 0.11 μg/kg (median; 5th percentile–95th percentile = 0.04–0.58 μg/kg; n = 24) in body lotions, 0.22 μg/kg (0.04–0.38 μg/kg, n = 10) in moisturizing lotions, 0.67 μg/kg (0.30–1.33 μg/kg, n = 8) in blemish balms, 0.16 μg/kg (0.06–7.43 μg/kg, n = 11) in bleaches, 0.13 μg/kg (0.04–0.98 μg/kg, n = 34) in skin lightning (fairness) creams manufactured within the country, and 9.24 × 106 μg/kg (2.92 × 106–3.17 × 107 μg/kg, n = 14) in imported skin lightning (fairness) creams, much higher than the 1 ppm (1 ppm = 103 μg/kg) regulatory limit. Probabilistic human health risk assessment for adult women (age > 21 y) revealed that computed hazard quotients from dermal exposure to the high-mercury fairness creams were >100 in all cases. The mass of mercury entering into the society via skin-care products is highly sensitive to the mass of high-mercury fairness creams that is imported to India; ten tonnes of import can introduce 29–317 kg of mercury every year. As such, analysis and labeling of mercury contents in skin-care products by manufacturers, and raising awareness among regulatory authorities to restrict the import of high-mercury fairness creams, is required.

Is Food Irrigated with Oilfield-Produced Water in the California Central Valley Safe to Eat? A Probabilistic Human Health Risk Assessment Evaluating Trace Metals Exposure.

Reuse of oilfield‐produced water (OPW) for crop irrigation has the potential to make a critical difference in the water budgets of highly productive but drought‐stressed agricultural watersheds. This is the first peer‐reviewed study to evaluate how trace metals in OPW used to irrigate California crops may affect human health. We modeled and quantified risks associated with consuming foods irrigated with OPW using available concentration data. The probabilistic risk assessment simulated OPW metal concentrations, crop uptake, human exposures, and potential noncancer and carcinogenic health effects. Overall, our findings indicate that there is a low risk of ingesting toxic amounts of metals from the consumption of tree nuts, citrus, grapes, and root vegetables irrigated with low‐saline OPW. Results show increased arsenic cancer risk (at 10−6) for adult vegetarians, assuming higher consumption of multiple foods irrigated with OPW that contain high arsenic concentrations. All other cancer risks are below levels of concern and all noncancer hazards are far below levels of concern. Arsenic risk concerns could be mitigated by practices such as blending high‐arsenic OPW. Future risk assessment research should model the risks of organic compounds in OPW, as our study focused on inorganic compounds. Nevertheless, our findings indicate that low‐saline OPW may provide a safe and sustainable alternative irrigation water source if water quality is adequately monitored and blended as needed prior to irrigation.

Fate and contaminant transport model-driven probabilistic human health risk assessment of DNAPL-contaminated site

In this study, fate and contaminant transport model-driven human health risk indexes were calculated due to the presence of dense non-aqueous phase liquids (DNAPLs) in the subsurface environment of air force base area in Florida, USA. Source concentration data of DNAPLs was used for the calculation of transport model-driven health risk indexes for the children and adult sub-population via direct oral ingestion and skin dermal contact exposure scenario using 10,000 Monte Carlo type simulations. The highest variation in the probability distribution of transformed DNAPL compound (cis-dichloroethene (cis-DCE) > vinyl chloride (VC)) was observed as compared to parent DNAPL (tetrachloroethene (PCE)) based on the 50-year simulation timespan. Transformed DNAPL compounds (VC, cis-DCE) posed the highest risk to human health for a longer duration (up to 15years) in comparison to parent DNAPL (PCE), as non-carcinogenic hazard quotient varied from 400 to 1100. Carcinogenic health risks were observed as 3-order of magnitude higher than safe limit (HQSafe < 10-6) from 2nd to 5th year timespan and fall in the high-risk zone, indicating the need for a remediation plan for a contaminated site. Variance attribution analysis revealed that concentration, body weight, and exposure duration (contribution percentage - 70 to 95%) were the most important parameters, highlighting the impact of dispersivity and exposure model in the estimation of risk indexes. This approach can help decision-makers when a contaminated site with partial data on hydrogeological properties and with higher uncertainty in model parameters is to be assessed for the formulation of remediation measures.

Low-temperature thermal desorption and secure landfill for oil-based drill cuttings management: Pollution control, human health risk, and probabilistic cost assessment

Oil-based drill cuttings (OBDCs) were managed in two scenarios including low-temperature thermal desorption (LTTD) and secure landfill through a case study. The removal of polycyclic aromatic hydrocarbons (PAHs) and heavy metals in OBDCs by LTTD under different conditions was investigated. Probabilistic human health risk assessment was performed to quantify the health risk posed to waste management workers under the two scenarios, while the associated costs were also analyzed. The results show that LTTD at 300 °C for >20 min could remove 96.27% of PAHs in OBDCs but its removal effect on heavy metals was not significant. It was found that cancer risks posed by PAHs in both securely landfilled and LTTD-treated OBDCs were not significant (<1e-06); however, significant cancer risks (7.95e-05–9.45e-05) were identified for exposure to toxic heavy metals. Increased health risk was observed as a result of exposure to LTTD treatment residues compared to securely landfilled OBDCs. Inhalation of chromium(VI) and oral ingestion of arsenic in OBDCs were critical exposure routes. Both cancer and non-cancer risks in the secure landfill scenario were negligible. The cost analysis results suggest that LTTD combined with stabilization/solidification could be more economically attractive than secure landfill for the handling of OBDCs.

Probabilistic human health risk assessment associated with fluoride and arsenic co-occurrence in drinking water from the metropolitan area of San Luis Potosí, Mexico.

A major public health concern in Mexico is the natural contamination of groundwater with fluoride and arsenic. Therefore, this work aimed to evaluate the magnitude of human health risk after determining fluoride and arsenic concentrations in groundwater samples (n = 50) from the Metropolitan area of the city of San Luis Potosi, Mexico. Fluoride levels in water were determined via a potentiometric method using an ion-selective electrode. Arsenic concentrations in water samples were determined with an Atomic Absorption technique. Subsequently, a probabilistic health risk assessment was developed (Monte Carlo Analysis). Fluoride levels in water ranged from 0.20 to 3.50mg/L. For arsenic, the mean level found in the assessed water samples was 15.5 ± 5.50μg/L (range: 2.50-30.0μg/L). In addition, when the probabilistic health risk assessment was completed, a mean HI (cumulative hazardous index) of higher than 1 was detected, indicating a high NCR (non-carcinogenic risk) for children and adults. According to the results found in this study, exposure protection campaigns are imperative in the Metropolitan area of the city of San Luis Potosí, Mexico, to successfully diminish exposure to arsenic and fluoride and, as a consequence, decrease the NCR in the population living in that region of Mexico.

Probabilistic human health risk assessment of linear alkylbenzene sulfonate (LAS) in water samples from Anzali Wetland, southwest of the Caspian Sea

Linear alkyl benzene Sulfonate (LAS) is a major anionic surfactant utilized in detergents around the world and is subsequently a ubiquitous water contaminant. This paper deals with assessing human health risk due to LAS in Anzali Wetland between different age groups. Water samples were collected from 50 stations in the wetland. LAS concentration was determined by spectrophotometry at 650 nm. The risk quotients (RQ) index was used to assess the human health risk assessment of LAS in the wetland. Based on the results, the health risk index was lower than 0.2 in all stations, indicating that there is no LAS contaminant risk for human health in this wetland. However, due to the presence of the different unregulated discharge of wastewater to the wetland, without strong policies to control and management, the risk of contamination may increase in the future.

Multi-pathway human exposure risk assessment using Bayesian modeling at the historically largest mercury mining district.

The largest mercury (Hg) mining district in the world is located in Almadén (Spain), with well-known environmental impacts in the surrounding ecosystem. However, the impact of mercury on the health of the inhabitants of this area has not been documented accordingly. This study aims to carry out a probabilistic human health risk assessment using Bayesian modeling to estimate the non-carcinogenic risk related to Hg through multiple exposure pathways. Samples of vegetables, wild mushrooms, fish, soil, water, and air were analyzed, and adult residents were randomly surveyed to adjust the risk models to the specific population data. On the one hand, the results for the non-carcinogenic risk based on Hazard Quotient (HQ) showed unacceptable risk levels through ingestion of Hg-contaminated vegetables and fish, with HQ values 20 and 3 times higher, respectively, than the safe exposure threshold of 1 for the 97.5th percentile. On the other hand, ingestion of mushrooms, dermal contact with soil, ingestion of water, dermal contact with water and inhalation of air, were below the safety limit for the 97.5th percentile, and did not represent a risk to the health of residents. In addition, the probabilistic approach was compared with the conservative deterministic approach, and similar results were obtained. This is the first study conducted in Almadén, which clearly reveals the high levels of human health risk to which the population is exposed due to the legacy of two millennia of Hg mining.

Probabilistic human health risk assessment of perfluorooctane sulfonate (PFOS) by integrating in vitro, in vivo toxicity, and human epidemiological studies using a Bayesian-based dose-response assessment coupled with physiologically based pharmacokinetic (PBPK) modeling approach

BackgroundEnvironmental exposure to perfluorooctane sulfonate (PFOS) is associated with various adverse outcomes in humans. However, risk assessment for PFOS with the traditional risk estimation method is faced with multiple challenges because there are high variabilities and uncertainties in its toxicokinetics and toxicity between species and among different types of studies. ObjectivesThis study aimed to develop a robust probabilistic risk assessment framework accounting for interspecies and inter-experiment variabilities and uncertainties to derive the human equivalent dose (HED) and reference dose for PFOS. MethodsA Bayesian dose-response model was developed to analyze selected 34 critical studies, including human epidemiological, animal in vivo, and ToxCast in vitro toxicity datasets. The dose-response results were incorporated into a multi-species physiologically based pharmacokinetic (PBPK) model to reduce the toxicokinetic/toxicodynamic variabilities. In addition, a population-based probabilistic risk assessment of PFOS was performed for Asian, Australian, European, and North American populations, respectively, based on reported environmental exposure levels. ResultsThe 5th percentile of HEDs derived from selected studies was estimated to be 21.5 (95% CI: 10.6–36.3) ng/kg/day. After exposure to environmental levels of PFOS, around 50% of the population in all studied populations would likely have >20% of increase in serum cholesterol, but the effects on other endpoints were estimated to be minimal (<10% changes). There was a small population (~10% of the population) that was highly sensitive to endocrine disruption and cellular response by environmental PFOS exposure. ConclusionOur results provide insights into a complete risk characterization of PFOS and may help regulatory agencies in the reevaluation of PFOS risk. Our new probabilistic approach can conduct dose-response analysis of different types of toxicity studies simultaneously and this method could be used to improve risk assessment for other perfluoroalkyl substances (PFAS).

Indices of Water Quality and Pesticide Monitoring Survey in Lake of Western Co?te d’Ivoire and Its Human Risk Assessment

The aims of the work were to study the current quality of the water in Lake DOHOU used for drinking water supply through several physical, chemical analyses and using water quality indices (WQI). In addition, the question was whether the populations are at risk after drinking water of lake following a reduction of 50% and 75% in the median and maximum values of pesticides. Thus, the results of the pesticide monitoring program were incorporated into probabilistic human health risk assessment exercises. Water samples were collected over a period of one year. Pesticides were subjected to solid phase extraction and then analyzed using gas chromatography coupled to tandem mass spectroscopy. The other parameters were measured according to conventional methods. The results showed that the most frequently detected pesticides were aldicarb (79%), simazine (79%) and monolinuron (44%). They also showed the mean values of concentrations exceeding 1.5 μg/L. Metoxuron detected at a frequency of 29% showed the maximum average concentration (13.46 μg/L). Nearly 98% of the sampling points had at least one substance with an average concentration above the quality standard (0.1 μg/L) and 80% did not meet the total concentration standards. Cumulative risk quotient estimates after 50% or 75% abatement for frequently identified pesticides were greater than unity when extreme values for adults and children were considered. To determine the suitability of water for aquatic life, drinking water consumption and drinking water production, the water quality index (WQI), the heavy metal pollution (HPI) and the heavy metal evaluation (HEI) were calculated. The poor quality of the water was mainly related to pesticides, organic matter and microbiological parameters. Most of the nutrients and metals studied were often below the standards of drinking water and aquatic life. The Water Quality Index (WQI) has shown that water quality is degrading for these three modes of use and ranges from poor to marginal. The coupling of monitoring data with probabilistic estimates of human risks could be used by the Ivorian authorities to propose effective pollution management plans.

Probabilistic human health risk assessment of groundwater contamination due to metal leaching: A case study of Indian dumping sites

In the present study, a probabilistic human health risk assessment (HHRA) due to metal leaching was conducted for five major dumping sites of India. Observed data of leachate/groundwater samples near dumping sites were used in calculating the non-carcinogenic hazard quotients (HQs) for the children and adults via oral ingestion and dermal contact exposure scenario using 10,000 Monte Carlo type simulations. Variance attribution analysis was performed to determine the uncertainty contribution of input parameter towards variance in the hazard quotient. HQs for fly-ash open dump, Nashik were found to be varying from 1 to 9000, indicating a cause of concern for people living nearby. The ranking order of dumping sites for posing a risk was found as Fly-ash dumping site, Nashik > Ariyamangalam open dump > Okhla, Delhi > Ghazipur, Delhi > Bhalswa dump, Delhi. Variance attribution analysis indicated that the body weight (BW) and exposure duration (ED) contributed about 35% to 55% towards the overall uncertainties of estimated HQs for the child subpopulation, while, for adult subpopulation, ED was observed to be a primary contributor (>95%). Results indicated that more information is required for characterizing the exposure duration of children and adults for effective HHRA that can help risk managers.

Probabilistic human health risk assessment of arsenic under uncertainty in drinking water sources in Jiangsu Province, China.

Concentrations of arsenic (As) in 65 drinking water sources in Jiangsu Province of China were analyzed from January 2013 to December 2015. The drinking water sources are classified into five water systems of the Yangze River, the Taihu Lake, the Huai River, the Yishusi River, and other lakes or reservoirs, which are termed as WS-A, WS-B, WS-C, WS-D, and WS-E, respectively. Health risk assessments associated with As in terms of total carcinogenic risk and total hazard index were performed for children (0-5years), teenagers (6-17years), and adults (≥ 18years), respectively. Probabilistic risk assessments were obtained by applying Monte Carlo approach with consideration of uncertainty. The results indicated that in drinking water sources of WS-A, WS-C, and WS-D, maximum concentrations of As were 28μg/L, 40μg/L, and 17μg/L, respectively, which were higher than 10μg/L recommended by the World Health Organization occurred. Based on the samples investigated in this study, the mean health risks are the highest in drinking water source WS-D and lowest in WS-E for both male and female children, teenagers, and adults. For drinking water source WS-A, the health risks of male children, male teenagers, and female adults are higher than female children and female teenagers, and male adults. However, for drinking water sources WS-B, WS-C, WS-D, and WS-E, the health risks of female children, male teenagers, and female adults are higher than male children, female teenagers, and male adults. The highest health risks occurred in female children consuming drinking water from WS-D. The sensitivity analysis indicated that the concentration of As is the primary factor for carcinogenic risk of all the five water systems. The results obtained can provide meaningful information for risk managers in Jiangsu Province.

Probabilistic Human Health Risk Assessment of Heavy Metal Intake via Vegetable Consumption around Pb/Zn Smelters in Southwest China.

Vegetable contamination in mining and smelting areas has resulted in high dietary intakes of heavy metals, which pose potential health risks to local residents. In this study, paired soil-vegetable samples were collected around Pb/Zn smelters in Southwest China. Probabilistic risks to local residents via vegetable consumption were evaluated with a Monte Carlo simulation. The mean concentrations of As, Cd, Cu, Pb, and Zn in the soils were 116.76, 3.59, 158.56, 196.96, and 236.74 mg/kg, respectively. About 38.18%, 58.49%, and 52.83% of the vegetable samples exceeded the maximum allowable concentrations for As, Cd, and Pb, respectively. The daily dietary intake of As, Cd, and Pb exceeded the provisional tolerable daily intakes for local residents, with children showing the highest intake via vegetable consumption. The percentages of the target hazard quotients of As, Cd, and Pb for local residents exceeding the safe value of one were about 95%, 50%, and 25%, respectively. The 95th percentiles of the hazard index for children, adolescents, and adults were 15.71, 11.15, and 9.34, respectively, indicating significant risks to local residents, especially children. These results highlight a need to develop effective strategies to reduce heavy metal contamination and exposure to protect human health.