Contamination Risk Assessment Research Articles

Occurrence and Environmental Risk Assessment of Contaminants of Emerging Concern in Brazilian Surface Waters.

We investigated the occurrence and the environmental risk of eight contaminants of emerging concern (CECs; acetaminophen, naproxen, diclofenac, methylparaben, 17β-estradiol, sulfathiazole, sulfadimethoxine, and sulfamethazine) in three Brazilian water bodies, namely, the Monjolinho River Basin (São Paulo State), the Mogi Guaçu River (São Paulo State), and the Itapecuru River (Maranhão State) in three sampling campaigns. The CECs were only quantified in surface water samples collected at the Monjolinho River Basin. Acetaminophen, naproxen, and methylparaben were detected in the range of <200 to 575.9 ng L-1, <200 to 224.7 ng L-1, and <200 to 303.6 ng L-1, respectively. The detection frequencies of the three measured compounds were between 33% and 67%. The highest concentrations of CECs were associated with intense urbanization and untreated sewage discharge. Furthermore, CEC concentrations were significantly correlated with total organic carbon, electrical conductivity, and dissolved oxygen levels, suggesting that domestic pollution from urban areas is an important source in the distribution of CECs in the Monjolinho River Basin. The environmental risk assessment indicated a high risk for acetaminophen (risk quotient [RQ] values between 2.1 and 5.8), a medium risk for naproxen (RQs between 0.6 and 0.7), and a low risk for methylparaben (RQs < 0.1) to the freshwater biota of the Monjolinho River Basin. Our findings show potential threats of CECs in Brazilian water bodies, especially in vulnerable areas, and reinforce the need for improvements in environmental regulations to include monitoring and control of these compounds in aquatic systems. Environ Toxicol Chem 2024;43:2199-2210. © 2024 SETAC.

In vitro tungsten bioaccessibility in Chinese residential soils: Implications for human health risk assessments and soil screening level derivation

Tungsten (W) contamination presents emerging environmental challenges, necessitating the need to establish soil screening levels (SSLs), especially for residential soils. This study assessed the health exposure risk and derived national and regional residential SSLs for W in Chinese residential soils, incorporating machine-learning prediction of in-vitro soil W bioaccessibility. We analyzed 204 residential soil samples collected across 24 provinces, recording a wide range of W concentrations (0.01–3063.2 mg/kg). Synchrotron-based X-ray fluorescence spectroscopy, chemical extractions, and random forest modeling indicated that the key determinants of soil W bioaccessibility were soil pH, cation exchange capacity, organic matter, and clay contents. Monte Carlo simulations demonstrated that soil W contamination predominantly results in noncarcinogenic health risks to residents via oral exposure, especially in mining-affected regions. A national residential SSL (NRSSL) of 35.5 mg/kg and regional residential SSLs (RRSSLs) of 34.5–49.2 mg/kg were established. Incorporating predicted bioaccessibility increased the NRSSL to 73.8 mg/kg and the RRSSLs to 69.8–112.5 mg/kg. Southern China, which is rich in W ore, exhibited lower RRSSLs, underscoring a need for enhanced safety management. Our framework and findings provide a robust scientific foundation for future soil contamination risk assessment studies, and we present customized SSLs that can guide targeted W risk control strategies.

Mapping Arsenic Contamination and Health Risk Assessment of Arsenic in Agricultural Soils of Eastern India

Mapping Arsenic Contamination and Health Risk Assessment of Arsenic in Agricultural Soils of Eastern India

Heavy metal contamination and human health risk assessment in the soils grown field crops in Antalya, Türkiye

ABSTRACT Soil pollution results from heavy metals has become a severe environmental concern. Heavy metals pose a risk to human health by entering the food chain. The aim of this study was to determine the concentrations, sources and potential ecological and human health risks of heavy metals in soils which grown field crops in Antalya, Turkey. Soil samples were collected at depths of 0–30 cm from 292 fields and concentrations of cadmium (Cd), lead (Pb), nickel (Ni), chromium (Cr), cobalt (Co), iron (Fe), manganese (Mn), copper (Cu) and zinc (Zn) were determined. The mean concentrations of total Cd, Pb, Ni, Cr, Co, Fe, Mn, Cu and Zn were 4.73, 68.67, 152.74, 98.52, 24.77, 28098, 823, 42.72 and 62.85 mg kg−1, respectively. These results showed that the average concentrations of Cd, Pb, Ni, Cr, Co, Cu and Mn exceeded the Upper continental crust average. Enrichment factor (EF), geo-accumulation index (I geo) and contamination factor (CF) values of soils indicate serious enrichment for Cd. Principal component analyses (PCA) indicated that Co, Cr and Ni was lithogenic origins, but Fe and Pb concentrations were determined by lithological and anthropogenic sources. Hazard index (HI) values of heavy metals were < 1, suggesting that non-carcinogenic health risks to adult residents. In addition, the total carcinogenic risk (TCR) values except for Cr, suggesting that carcinogenic risks for residents were not expected. The results showed that children were more sensitive to the non-carcinogenic and carcinogenic effects of heavy metals.

Micro‐ and nano‐plastic loads in fish and macroinvertebrates in a tropical river

Abstract This study examines microplastic contamination in river macroinvertebrates and fish within a rapidly urbanising tropical catchment, and provides data on the quantity of microplastics ingested by various taxonomic and functional feeding groups. We employed both a widely used low‐resolution visual inspection method, capable of identifying microplastics ranging from 0.1 to 5 mm, and a novel automated method specifically designed to identify smaller plastics in the nano size range, from 0.004 to 0.1 mm. Analysis using the low‐resolution method indicated that a significant portion of fish (95%) and macroinvertebrates (44%) contained larger microplastics. The composition of microplastic within the animals differed from that in river water and on the river bed: microplastics in the water and on the bed were predominantly fibres (98% and 92% respectively), whereas the animals exhibited a more even mix of fibres (c. 35%), fragments (c. 43%), and film (c. 22%). Microplastic loads in aquatic organisms correlated with feeding group and body size, although patterns were not always consistent. Larger individuals generally contained more microplastic, especially among macroinvertebrates, but this trend was not observed uniformly among fish species. Additionally, differences in body loads among macroinvertebrate taxa and feeding groups varied depending on whether loads were expressed per individual or per unit weight. Use of the high‐resolution enumeration method revealed a substantially higher microplastic count compared to the low‐resolution method, highlighting the potential underestimation of contamination levels by the latter. The study underscores the non‐random uptake of microplastics by aquatic biota, influenced by feeding mode, and stresses the necessity of high‐resolution sample processing for accurate quantification of contamination levels and risk assessment for smaller organisms.

Regional Assessment of Groundwater Contamination Risk from Crude Oil Spillages in the Niger Delta: A Novel Application of the Source-Pathway-Receptor Model

AbstractOnshore oil spills are known for their disastrous environmental impacts and potential to cause lasting damage to underlying groundwater. The Niger Delta is particularly vulnerable to widespread spillages linked to extensive oil exploration, transportation, and theft-related incidents. This research employed a geospatial approach in formulating risk equations, based on the source-pathway-receptor (S-P-R) model using multiple openly available data sets, to assess groundwater contamination risk in the Niger Delta Region (NDR), Nigeria. To develop the overall risk equation, the study combined fourteen thematic data layers including the volume of oil spilled, type of spill, slope, elevation, proximity to spill site, pipeline, oil wells and streams, drainage density, mean annual precipitation and population density. These layers were integrated into source potency, pathway transmissivity, and receptor susceptibility. The NDR was systematically categorized into low, moderate, and high groundwater risk zones. The delineation revealed that high-risk zones predominantly span the central areas, extending from southeast to northwest, effectively encircled by regions of low to medium risk located in both the northern and southern extents of the delta. The efficacy of the risk model was corroborated by existing knowledge. Moderate to high-risk zones were found to be in about 16% of the NDR, revealing previously unknown areas of risk. This spatial configuration underscores a significant gradient in contamination risk across the NDR, with the central corridor emerging as a critical focus for groundwater protection and remediation efforts. In line with UN Sustainable Development Goal (SDG) #6, this study recommends targeted strategies to ensure clean water provision in these identified high-risk areas. By leveraging the S-P-R model within this complex and sensitive ecological area, this research both advances environmental risk assessment and sets a precedent for future large-scale environmental risk assessments utilizing open-source data.

Assessment of spatiotemporal risks for nationwide groundwater nitrate contamination

National assessments of groundwater contamination risks are crucial for sustaining high-quality groundwater supplies. However, traditional methods often treat groundwater contamination risk as a steady-state indicator without considering spatiotemporal variation in risk, both geographically and over time, caused by anthropogenic and climatic factors. In this work, XGBoost, a tree-based algorithm, was applied to comprehensively analyze the drivers of groundwater contamination from nitrate, using data on 13 physical features (as used by the index-based ranking method DRASTIC) and 30 anthropogenic features from 1985 to 2010 in the contiguous United States (CONUS). The results indicate that physical features controlling the transport processes, particularly those affecting contaminant travel time from land surface to groundwater (depth to water table and transmissivity), were the dominant factors for nitrate contamination in groundwater. This was followed by features representing the potential nitrogen loading. Positive correlations between most features and the nitrogen loading time (year) were found, suggesting their growing influence on contamination risk. Based on the drivers identified for nitrate concentrations exceeding 10 mg/L in groundwater and their varying temporal contributions, this study proposes a reformulated index-based method for contamination risk assessment. With this method, an overall accuracy of around 70 % was achieved based on the validation data set. The predicted high-risk areas are mainly intensive irrigation regions, such as the High Plains, northern Midwest, and Central Valley. This new approach contributes to a more accurate and effective assessment of the contamination risks of groundwater on a regional and national scale under temporally varying environmental conditions.

Microplastic Contamination and Ecological Risk Assessment in Tropical Riverine Surface Water of Selangor River Basin, Malaysia

Microplastic Contamination and Ecological Risk Assessment in Tropical Riverine Surface Water of Selangor River Basin, Malaysia

Ecological and human health risk assessment of heavy metal contamination in soils of major industrial estates of Tamil Nadu, India

ABSTRACT This study endeavoured to determine the current status of heavy metal contamination in soils around leather industrial areas of Tamil Nadu and the associated environmental and human health risks. Accordingly, 31 soil samples were examined using the total reflection X-ray fluorescence (TXRF) spectroscopy technique. From TXRF results, the mean concentrations of heavy metals (mg kg−1, dry weight) were obtained in the trend of Fe (9234.03) > Al (592.00) > Cr (194.99) > Sr (148.76) > Mn (137.61) > Cl (81.79) > Zn (38.97) > Cu (38.33) > V (36.78) > Pb (31.18) > Ni (9.81) > As (1.12). The pollution indices such as geo-accumulation index (Igeo), contamination factor (CF), and enrichment factor (EF) revealed the significant contaminants in the study area. The hazard index (HI) indicated that non-carcinogenic risk (NCR) due to heavy metals were negligible for both adults and children (HI < 1). In addition, total cancer risk (TCR) showed carcinogenic risk (CR) for adults (TCR = 1.38 × 10−4) and children (TCR = 1.27 × 10−3) are moderate and higher, respectively. Multivariate statistical analyses such as Pearson correlation analysis (CA), hierarchical cluster analysis (HCA), and factor analysis (FA) revealed that the heavy metals derived from various sources such as lithogenic and anthropogenic. Overall, special concern is advised to the inhabitants, especially with regard to children, in the study area about the health risks due to the anthropogenic inputs.

Animal dietary exposure in the risk assessment of contaminants in feed.

EFSA performs dietary exposure assessments for food-producing and non-food-producing animals to deliver risk assessment for mandates on the presence of contaminants in feed. The CONTAM and FEEDAP Panels identified the need to update the animal dietary exposure assessment model used in those assessments in CONTAM Scientific Opinions since 2011 in cases where insufficient occurrence data are available on species specific compound feeds. The Panels proposed in this statement a series of model diets based on groups of feed materials with the possibility to use different feed materials in their formulation. The Panels considered that the currently proposed model diets cover the need of the CONTAM Panel to assess the dietary exposure of animals to contaminants in feed.

Monitoring and assessment of contamination and ecological risk of heavy metals in Hezarpich surface soils

Monitoring and assessment of contamination and ecological risk of heavy metals in Hezarpich surface soils

Causal relationships of health risk of air pollution in industrial area

Air contamination is one of the serious problems for the environment and the health of society. Air contamination risk assessment, health effects assessment tools are used to identify the place and time of public health effects and risk prevention strategies to reduce negative health effects. Considering that there may be a relationship between factors affecting risk, in this study, interactions between them are investigated using Fuzzy Decision Test and Experimental Evaluation Method (fuzzy DEMATEL). The cause of the health air contamination risk in an industrial area are the activity of industrial complexes and port (D+R=45.98, D-R=2.09) and the presence of hydrogen sulfide (46.82, 2.61), benzene (50.87, 2.87), sulfur dioxide (43.87, 4.32) and PM10 (53.51, 5.63) and the effects of these factors will affect the amount of carbon monoxide (39.56, -4.47), ozone (38.80, -4.20), nitrogen dioxide (50.33, -1.62) and PM2.5 (44.18, -1.26). Hospitals and nursing homes (49.01, -2.58), schools (50.99, -0.59), storage and industrial facilities, roads (45.72, -0.59), urban core (51.38, -0.55) and Natural zones, agriculture and waterways (48.86, -0.17) are affected by other factors. Population density is also affected by cause factors. Population density has a two-way relationship with PM2.5. The main human and social factors include GDP per capita and urbanization rate. Hydrogen sulfide has a one-way relationship with population density. People who work in certain industries may be exposed to higher amounts of hydrogen sulfide than the general population. These industries include the production of rayon textiles, pulp and paper factories, oil and natural gas drilling operations, and wastewater treatment plants. Therefore, by controlling the activity of industrial complexes, port and the amounts of hydrogen sulfide, benzene, sulfur dioxide and PM10 in the ambient air can be prevented from the effects after that.

Assessment of Heavy Metal Contamination and Potential Health Risk of Selected Fish Species in Dhaka District

Fish is a rich source of quality protein and fatty acids. Bangladesh's average daily fish consumption is 67.8 grams per people. Fish species are also prone to heavy metal contamination from their surrounding environment. The main objective of this research was to assess the degree of risk associated with the consumption of various fish species in Dhaka, Bangladesh. Three fish species—Tilapia (Oreochromis mossambicus), Shorputi (Systomus sarana), and Mola (Amblypharyngodon mola)—from three local markets in Savar Union, Dhaka, Bangladesh, were selected for analysis. The Kjeldahl technique, Folch method, and several formulae were used to determine the protein, fat, ash, and moisture content for the proximate analysis. The concentration of heavy metals was determined using Atomic Absorption Spectrophotometry (AAS). The estimated daily intake (EDI), target hazard quotient (THQ), total target hazard quotient (TTHQ), hazard index (HI), and cancer risk (CR) were used to evaluate the danger to human health. Tilapia had the highest moisture and lipid content, whereas Shorputi and Mola had the highest protein and ash contents, ranging from 20.77% to 18.16%, respectively. The mean concentration of heavy metals in fish was determined to be Pb&gt;Ni&gt;Cr&gt;Cd in this study. Every fish species had extremely high levels of lead (Pb), with the Shorputi fish having the highest levels. Fish from the Shorputi species had the highest EDI value. Pb&gt;Ni&gt;Cr&gt;Cd was the trace element EDI for adults. Among all species, only Pd had a THQ value higher than 1. The CR value across all species were within E-3 and E-6 range, while the HI value was &gt;1. In conclusion, the highest average Pb concentrations were detected in Shorputi, while the highest amounts of Cd, Cr, and Ni were observed in Tilapia. The findings of this study recommended that the Bangladeshi government regularly assess the levels of dangerous heavy metal and metalloid contamination in the daily meals of its citizens in order to enforce regulatory limits and determine the likelihood of long-term exposure. Bioresearch Commu. 10(2): 1524-1531, 2024 (July)

Assessment of contamination and potential ecological risks of heavy metals in the bottom sediments of Lake Mainit, Philippines

Lake Mainit is considered an important communal resource in the provinces of Surigao del Norte and Agusan del Norte, which makes the lake a rich natural resource with great ecological value. Calculations of contamination factor (Cf), enrichment factor (Ef), degree of contamination (Cd), modified degree of contamination (mCd), and ecological risk index (MRI) were utilized to diagnose the level of anthropogenic and environmental risk of heavy metal accumulation in bottom sediments. Cf throughout all stations indicates that Lake Mainit is highly contaminated with Ni. Ef mainly was greater than one across all stations, with extremely severe enrichment of Ni. Ni and Cr have a high degree of contamination among all stations. The general MRI across all stations of Lake Mainit is at very high risk. It is evident that Lake Mainit is polluted and will continue to be polluted if fast and reliable responses, both for monitoring and environmental protection, are not provided. Hence, there is a need for comprehensive management of Lake Mainit to help restore its health both from the residents and the acting LGUs of the surrounding municipalities of Lake Mainit.

Potentially toxic elements contamination and ecological risk assessment in surface sediments of Moulouya Estuary (Northeastern, Morocco)

Potentially toxic elements (PTEs) in aquatic ecosystems are a major environmental concern posing serious risks to aquatic life and human health. Understanding their distribution, sources, and effects is crucial for effective environmental management and the protection of biodiversity and natural resources. This study assessed the variability, bioavailability, contamination degree, and ecological risks of PTEs in surface sediments of the Moulouya Estuary. The levels of PTEs were determined using an inductively coupled plasma-optical emission spectrometry (ICP-OES). The mean concentrations of PTEs can be classified in the following order: Zn > Cr > As > Pb >Cu > Cd. The highest values were found in sites (S2, S4, and S5) that receive metals from anthropogenic activities. The mineralogical study showed that the sediment studied is dominated by Ca, which influences the PTEs mobility and makes them bioavailable in the aquatic environment, which means aquatic organisms can easily assimilate them. The PTEs contamination degree was determined by several pollution indices (CF, CD, PLI, EF, Igeo), which indicate that surface sediment shows low to moderate contamination levels. However, the Potential Ecological Risk indicates a moderate to considerable risk in the study area. The multivariate analysis indicates that As, Zn, Cr, Pb, and Cu are derived from anthropogenic activities (urban wastewater, fertilizers, and fishing boats), while Cd could have mixed sources. The results highlight suggest that human activities pose an ecotoxicological risk in the Moulouya Estuary. To minimize these risks and protect the aquatic ecosystem and human health, periodic monitoring and management strategies should be continued. These measures will enable early detection of changes in PTE levels and the implementation of the necessary interventions to reduce their harmful effects.

Heavy metal(loid)s contamination and ecological-health risk assessment of coastal sediment from Salwa Bay, Saudi Arabia

Salwa Bay is an elongated, narrow bay which extends southwards from the Gulf of Bahrain down to the Saudi-Qatari border, separating the peninsula of Qatar from Saudi Arabia. The present study aims to investigate the degree of heavy metal(loid)s (HMs) contamination and the associated health risks in surface sediments of the Salwa Bay, Saudi Arabia. Thirty samples were collected for analysis of Ni, Cu, Cr, Pb, Zn, and As using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Several contamination and health risk indices, and multivariate analysis were applied. The following order was detected for average concentrations of metal(loid)s (μg/g dry weight): Cr (5.56) > Zn (4.63) > Ni (4.43) > As (2.34) > Pb (1.66) > Cu (1.51). The coastal sediments exhibit a significant enrichment in As, moderate enrichment in Pb, Zn, Cr, and deficiency to minimal enrichment for Ni, and Cu. Sediment quality guidelines indicated that HMs do not pose a risk to the benthic communities in Salwa Bay area. The average hazard index values ranged from 0.00002 to 0.0038 in adults and from 0.0002 to 0.0353 in children. This suggests that there is no significant possibility of non-carcinogenic effects to the people inhabiting the coastline of Salwa Bay. The results of the excess lifetime cancer risk (ELCR) for As, Cr, and Pb were below 1 × 10−4, indicating no carcinogenic health risk except for a few sediment samples showing elevated levels of Cr and As.

Human health risk assessment of microbial contamination and trace metals in water and soils of Chileka Township, Blantyre, Malawi

This study assessed nutrients and microbial contamination in water and soil samples from Chileka Township, Blantyre City, Malawi. Elevated total and fecal coliforms (1300 cfu/100 mL and 290 cfu/100 mL) in groundwater (GW), and (34,000 cfu/100 mL and 8000 cfu/100 mL) in surface water (SW) were found, representing a risk of exposure to water-borne disease. While the criteria in the Malawi Standard for raw groundwater was mostly met, water from only 20% of the boreholes complied with the WHO requirements. Nitrate (NO3─) and Cl─ (47.8 mg/L and 263 mg/L) exceeded the WHO limits in GW. Cadmium (Cd) occurred in a few cases at concentrations up to 0.217 mg/L and 0.138 mg/L in GW and SW. Lead (Pb) and Cr were below detection limits, while Mn (0.319 mg/L and 0.640 mg/L) in GW and SW, and Fe (6.92 mg/L) in SW compromised taste. Though bacteriologically unfit for raw consumption by humans, both GW and SW chemically met FAO-acceptable limits for irrigation, and standards for livestock watering. The NO3─ and PO43─ maximum concentrations in soil were 58.9 mg/kg and 506 mg/kg, respectively. Lead (Pb) and Cd were not detected whereas Cr, Zn, Cu, Mn and Fe in soil were 27.7 mg/kg, 190 mg/kg, 60.4 mg/kg, 1307 mg/kg and 6552 mg/kg, respectively. Magnesium (Mg), Ca, Na and K were 20,523 mg/kg, 22,334 mg/kg, 544 mg/kg and 5758 mg/kg, respectively in soil. The human health risk assessment results, on the other hand, showed that at least 30% (6 out of 20) of the GW samples and 60% (3 out 8) of the SW samples had HI > 1 for adults, children and infants, indicating existence of non-carcinogenic risk. Similarly, at least 15% (3 out 20) of the GW samples and 18% (1 out of 8) of the SW samples had CR > 0.001 for adults, children and infants, suggesting a risk of developing cancer during a lifetime due to Cd exposure. Though both GW and SW are generally of good chemical quality, chronic exposure to nitrate and cadmium is a health risk in the area. The current trace metal levels are not worrisome, but soil nitrate and phosphate may need regular monitoring.

Mobility and health risk assessment of heavy metal contamination in drinking water of peri urban areas of District Muzaffargarh, Pakistan

Mobility and health risk assessment of heavy metal contamination in drinking water of peri urban areas of District Muzaffargarh, Pakistan

Elucidating Mycotoxin-Producing Aspergillus Species in River Water: An Advanced Molecular Diagnostic Study for the Assessment of Ecological Health and Contamination Risk

The primary goal of this research is to isolate mycotoxin-producing fungus from the Nagavali River. Examining isolated fungi involved analyzing their mycelium growth on culture media and detailed microscopic inspection. We employed PCR analysis utilizing universal primers ITS1 and ITS4 to accurately identify the species. Furthermore, we sequenced the amplified ITS region and rigorously analyzed the sequences using NCBI-BLASTn and the ITS2 database. The analysis found a high 96.38% genetic similarity to the Aspergillus flavus strain, resulting in a 600-base pair fragment size. The sequence was given the accession number OR536222 in the NCBI GenBank database. Phylogenetic analysis was performed to ascertain the particular strain of A. flavus and its source. Remarkably, this analysis led to the identification of a single new strain gene, which represents a novel discovery in the field of fungal research. These results underscore the vital significance of molecular techniques in promptly and precisely identifying organisms. This research enhances our understanding of mycotoxin contamination in water, providing valuable insights to improve detection and prevention strategies. It accentuates the overarching importance of conserving our water resources and upholding ecological equilibrium, ultimately safeguarding the well-being of both humanity and the environment.

Ecological and Health Risk Assessment of Soil Heavy Metal Contamination Along National Highway 107 in China

Ecological and Health Risk Assessment of Soil Heavy Metal Contamination Along National Highway 107 in China