Human Health Risk Assessment Research Articles

An insight into carcinogenic activity and molecular mechanisms of Bis(2-ethylhexyl) phthalate.

Di(ethylhexyl) phthalate (DEHP) is a ubiquitous environmental contaminant to which humans are exposed via multiple routes. Human health risk assessments for this substance have recently been updated, focusing on reproductive toxicity, including DEHP, in the list of chemicals classified as carcinogenic, mutagenic, or toxic to reproduction (CMR). Moreover, DEHP has also been defined as probably and possibly carcinogenic to humans based on its carcinogenicity in rodents. However, the mechanism of action of DEHP and its relevance in humans remain unclear. Rodent data suggests that DEHP induces cancer through non-genotoxic mechanisms related to multiple molecular signals, including PPARα activation, perturbation of fatty acid metabolism, induction of cell proliferation, decreased apoptosis, production of reactive oxygen species, and oxidative stress. According to the DEHP toxicological dataset, several in vitro cell transformation assays have been performed using different protocols and cellular models to produce different results. This study aimed to evaluate the carcinogenic potential of DEHP by using the A31-1-1 BALB/c-3T3 cell line in a standard cell transformation assay. Additionally, transcriptomic analysis was performed to explore the molecular responses and identify the affected toxicological pathways. Although DEHP treatment did not induce transformation in BALB/c-3T3 cells, the transcriptomic results revealed significant modulation of several pathways associated with DEHP metabolism, tissue-specific functions related to systemic metabolism, and basal cellular signaling with pleiotropic outcomes. Among these signaling pathways, modulation of cell-regulating signaling pathways, such as Notch, Wnt, and TGF-β, can be highlighted. More specific modulation of such genes and pathways with double functions in metabolism and neurophysiology underlies the well-known crosstalk that may be crucial for the mechanism of action of DEHP. Our findings offer evidence to support the notion that these models are effective in minimizing the use of animal testing for toxicity assessment.

Multivariate Statistical Analysis of Cosmetics Due to Potentially Toxic/Heavy Metal(loid) Contamination: Source Identification for Sustainability and Human Health Risk Assessment

Multivariate Statistical Analysis of Cosmetics Due to Potentially Toxic/Heavy Metal(loid) Contamination: Source Identification for Sustainability and Human Health Risk Assessment

Groundwater health risk assessment and its temporal and spatial evolution based on trapezoidal fuzzy number-Monte Carlo stochastic simulation: A case study in western Jilin province

The United States Environmental Protection Agency (USEPA) Four-step-Method (FSM) is a straightforward and extensively utilized tool for evaluating regional health risks, However, the complex and heterogeneous groundwater environment system causes great uncertainty in the assessment process. Triangular stochastic simulation (TSS) possesses certain advantages in solving uncertainty problems, but its inadequacy with discrete data reveals limitations in this aspect. To solve the above problems, this study proposes to construct trapezoidal fuzzy number-Monte Carlo stochastic simulation (TFN-MCSS) to compensate for the shortcomings of the first two methods. This method adopted trapezoidal fuzzy number (TFN) analysis to comprehensively consider the characteristics of a large dispersion of water quality monitoring data and the uncertainty of the human health risk assessment (HHRA) process. Concurrently, to overcome the subjectivity and uncertainty of artificially determining the interval of TFN in traditional methods, the slope was used to select the most probable interval value (TMPIV) of TFN combined with the α-truncated set technique (α-TST) and MCSS. Based on these, a TFN-MCSS was constructed and applied to groundwater HHRA in western Jilin Province. First, the groundwater chemical characteristic determination and water quality evaluation in western Jilin were performed to identify the main pollution indicators, and the health risk effects of pollutants in groundwater of different aquifers at different time periods on adults and children were evaluated using the TFN-MCSS. The uncertainty and sensitivity were analyzed, and the primary risk control indicators were identified and compared to FSM and TSS. The results reveal that TFN-MCSS was more sensitive to data and could reduce the uncertainty of assessment process. It indicated that over a 10-year period, the health risks associated with unconfined groundwater (UW) and confined water (CW) decreased by greater than 52 %. However, the highest total non-carcinogenic risk index (THI) was 1.3-fold higher than the safety threshold, and this posed a health risk.

Dietary exposure to polycyclic aromatic hydrocarbons-contaminated Talinum Triangulare grown along polluted river.

The research aims to evaluate the source, dispersion, and human health risk assessment of PAH-contaminated Talinum Triangulare grown along the polluted Ikpoba River. The freeze-dried vegetables were sonicated with dichloromethane for an hour and then concentrated using a rotary evaporator. The extract was purified using a glass column with anhydrous Na2SO4 and silica gel and analyzed using gas chromatography-mass spectrometry (GC-MS). The distribution of the contaminants showed that Pyrene < Benzo(a)anthracene ≤ Fluorene < Phenathrene ≤ Naphthalene ≤ Acenaphthene < Anthracene ≤ Acenaphthylene, while Pyrene < Benzo(a)anthracene < Fluorene < Phenathrene < Acenaphthalene ≤ Naphthalene < Anthracene < Acenaphthylene in wet and dry periods, respectively. The average ∑8 PAHs was 0.85mg/kg and 0.75mg/kg in wet and dry periods, respectively, and showed a decrease of 17.64% from wet to dry periods. The daily average dose revealed that the infant male and the adult female consumed the least and highest doses of T. Triangulare (TT), respectively. Furthermore, the hazard quotient and hazard index were < 1 for all the target groups, with adult females having higher values in both seasons. However, the incremental life cancer risk of the target group was between potential and high-potential cancer risk, with adolescent males and adult females more prone to low and high cancer risk, respectively. The isomer ratio and multivariate statistics revealed the sources of the PAH-contaminated TT to be more from pyrolysis.

Environmental and human health risk assessment of soils in areas of ore mineralization and past gold-mining activity.

The patterns of the potentially toxic elements (PTEs: Cr, Fe, Ni, Cu, Zn, As, Mo, Pb, Hg) distribution in soils were studied together with the health risk assessment in the area of ore mineralization, past gold activity, and tailing effects of the Sarala gold-ore group located in the Republic of Khakassia, Russia. High PTE concentrations were found in soils with the presence of potential negative impact on human health based on the following: local background investigation, according to statistics; geochemical, environmental, and human health risk calculations; and comparative analysis using international and local reference, such as continental crust, clarke, and permissible concentrations. Sources of PTE soil enrichment and pollution were statistically identified in ascending order of degree: geogenic (local background) < geogenic-technogenic (sites with geological exploration traces - trenches) < technogenic (waste tailings). The main pollutants are Hg and As which showed moderate to significant ecological risk. Negative impact of Cr on soils was found. The pollution degree and toxicity (moderate to significant) of other PTEs increase in the location of ore mineralization zone with exploration trenches and waste tailings. Arsenic poses a carcinogenic risk to adults and children upon contact with polluted soils and non-carcinogenic effect on children in areas affected by tailings and ore mineralization zone. The non-carcinogenic effect of Fe on children was found in soils of all sites. The results provide useful information regarding the studied PTEs and their impact on the environment and human health. Such information can be helpful for the state-level decision-making process when addressing solutions for contaminated areas.

High-risk ARGs (HRA) Chip: A high-throughput qPCR-based array for assessment of high-risk ARGs from the environment

The global surge in antibiotic resistance genes (ARGs) presents a serious public health challenge. While methods like metagenomic analysis and qPCR arrays have been instrumental in investigating ARG distributions and dynamics, the vast diversity of ARGs often complicates effective monitoring and risk assessment. Here, we developed a High-Risk ARGs (HRA) chip based on high-capacity quantitative PCR array targeting previously identified high-risk ARGs. These ARGs are known to be prevalent in human-related environments, exhibit gene mobility, and are present in ESKAPE pathogens. The HRA chip include 101 primer sets and the 16S rRNA gene as a reference. These primer sets consist of 34 obtained from previous studies, and 67 newly designed primer sets which were validated in silico and experimentally. Absolute quantification of targeted ARGs is accomplished by generating standard curves for all ARGs with serially ten-fold diluted mixed plasmids containing targeted ARG sequences. The amplification efficiencies of all ARGs exceed 99% via plasmid template dilution tests, suggesting high reliability in quantification. The performance of HRA chip is further evaluated by practical applications in environmental samples from wastewater treatment plants (WWTPs) and soils with various land use types and fertilization regimes. The results indicate the dynamics of high-risk ARGs during wastewater treatment process, and reveal the profiles of soil high-risk ARGs which is distinct from those derived via metagenomic approaches. These findings highlight the potentials of HRA Chip in the evaluation of anthropogenic impacts on the environmental resistome with a more focused spectrum of high-risk ARGs. Overall, the HRA Chip emerges as a powerful and efficient high-throughput tool for rapid detection and quantification of high-risk ARGs, facilitating comprehensive profiling of high-risk resistomes in environmental samples which is essential for human health risk assessment of ARGs.

The occurrence and human health risk assessment of total and aflatoxin B1 in selected food commodities in Bhutan

Aflatoxins are mycotoxins that contaminate staple foods globally and pose a significant health risk. To the best of our knowledge, information on the occurrence of aflatoxins in Bhutanese diets is scarce. This study aimed to estimate the aflatoxin levels in selected foodstuffs in Bhutan and determine the health risk associated with aflatoxin exposure. Ten different types of food commodities were randomly collected from farmers’ markets, shelves of supermarkets, and wholesale and retail shops from 20 districts of the country. The samples were subjected to analysis by an enzyme-linked immunosorbent assay for both total aflatoxins (B1, B2, G1 and G2) and aflatoxin B1. Among the 315 samples included, 48.81% and 79.35% were positive for total aflatoxins and aflatoxin B1, respectively. The overall mean total aflatoxin concentration was 11.49 ± 12.83 µg/kg, and that for B1 was 17.62 ± 23.99 µg/kg. The most prevalent food commodity with the highest aflatoxin contamination was chili products. In addition, the estimated daily intake and margin of exposure to aflatoxin B1 via the consumption of chili products ranged from 0.98 to 5.34 ng kg−1 bw day−1 and from 74.90 to 408.10, indicating a risk for public health. The liver cancer risk was estimated to be 0.01 and 0.007 cancers per year per 100,000 population resulting from the consumption of chili products. The present findings revealed the presence of total aflatoxins and aflatoxin B1 in the selected samples. The margin of exposure values was exorbitant, demanding a stringent public health measure. Notably, these results suggest the need for routine monitoring of aflatoxin contamination in the region and stress rigorous safety management strategies to reduce exposure.

Respiratory health assessment of outdoor workers exposed to urban air pollution based on satellite observations

Human health impact assessment due to air pollution is critical for evaluating environmental hazards. In this research, levels of three air pollutants (CO, NO2, and SO2) were estimated based on satellite data (sentinel-5p) to assess the air quality over three areas (Al-Mahaad Al-Dinni, Bus Stop, and Oil Company areas) at Banha city, Qalyobia in addition to evaluating the human health risks resulting from exposure to these air pollutants. Unlike the conventional approaches for human health risk assessment, which depend on in-situ air pollution measurements, in this study, the spatial distribution of the pollutants was acquired from satellite remote sensing for the period 2021–2022. The respiratory health assessment of 151 outdoor workers, exposed to air pollution in Banha City was conducted. Results showed that the highest concentration of the pollutants was found in areas of Bus Stop and Oil Company. Consequently, the percentage of predicted pulmonary function tests was significantly lower among those working in the Oil company area than those working in the Bus Stop and Al-Mahaad Al-Dinni areas. Additionally, 47.6 % of the studied group complained of nasal congestion and 67.5 % of them complained of wheezing, 30.5% of them had obstructive airway diseases. In conclusion, remotely sensed air quality data proved its efficiency in health impact studies which could be carried out in different regions globally with less cost than traditional measurement techniques. Urban pollution can influence outdoor workers with varied percentages according to their exposure rate to pollutants and work-related factors.

Tracking Trace Elements Found in Coffee and Infusions of Commercially Available Coffee Products Marketed in Poland.

Coffee is a source of micronutrients, including iron, zinc, copper, and manganese. It may also contain toxic metals, such as lead and cadmium. The effects of coffee on the human body may vary depending on its composition. The objective of this study was to assess the quality of ground and instant coffee with regard to the content of selected trace elements. The concentrations of trace elements, including copper, iron, manganese, and zinc, were determined by ICP-AES, while the levels of lead and cadmium were quantified by GF-AAS methods. Furthermore, the degree of coverage of the recommended intake of elements and the risk assessment for human health (EDI, THQ, PTMI, and TWI) were determined. Our findings indicate that the consumption of a cup of coffee provides the body with only small amounts of these elements. A coffee prepared from 6.33 g of ground coffee beans provides 0.08-1.52% of the RDA value, while a coffee prepared from 6.33 g of instant coffee provides 0.46-13.01% of the RDA, depending on the microelement. The low transfer to the brew (Pb = 7.1%; Cd = 30.0%) of the analyzed ground coffees renders them safe for the consumer, even at a consumption of six cups per day. The percentage of benchmark dose lower confidence limit (BMDL0.1) in the case of lead did not exceed 0.9%. The estimated value did not exceed 0.2% of the provisional tolerable monthly intake of cadmium (PTMI). None of the analyzed coffees exhibited any risk regarding the trace elements.

Heavy metal bioaccumulation in fish: ımplications for human health risk assessment in ten commercial fish species from Konya, Türkiye

Heavy metal bioaccumulation in fish: ımplications for human health risk assessment in ten commercial fish species from Konya, Türkiye

Biomonitoring of petroleum hydrocarbon residues in commercially important fish and shrimp species from a tropical coastal ecosystem Chilika, India: Associated human health risk assessment

Petroleum hydrocarbons (PHCs) residues in commercially important fish and shrimp species from Asia's largest brackish water lagoon, Chilika and their dietary risk factors like Bioaccumulation factor (BAF), Estimated dietary intake (EDI) and Exposure risk index (ERI) were investigated. The PHCs in water samples were found within the range of 2.21 to 9.41 μg/l; while in organisms, PHCs varied from 0.74 to 3.16 μg/g (wet weight). The lowest and highest PHCs concentration was observed in Etroplus suratensis (0.74 ± 0.12; crude fat 0.57 %) and Nematalosa nasus (3.16 ± 0.12; crude fat 6.43 %) respectively. From human health risk view point, the calculated BAF, EDI, ERI were within the prescribed safe limits. Our finding suggests that Nematalosa nasus can be used as biomonitor species for petroleum hydrocarbon contamination status for this ecosystem and also continuous pollution monitoring programs must be conducted by the concerned authorities to safeguard this important aquatic ecosystem.

Assessing microbiological and heavy metal pollution in surface waters associated with potential human health risk assessment at fish ingestion exposure

Fish represent a significant source of nutrients but also cause negative health effects due to their bioaccumulation capacity for pollutants. The aim of this study was to examine the transfer of metals from the water of several rivers (Somes, Tisa, Sasar, Lapus, Lăpusel) to fish (Caras sp) tissue (subcutaneous fat, muscles, liver, intestines, kidneys, gills, brain, and eyes) and to identify and assess the carcinogenic and non-carcinogenic health risks of Arsenic (As), Cadmium (Cd), Nickel (Ni), Manganese (Mn), Cooper (Cu), Lead (Pb), Chromium (Cr) and Zinc (Zn) through the ingestion of fish (muscles and subcutaneous fat tissues). The obtained results indicated that a diet consisting of fish is particularly vulnerable, particularly in children compared to adults. The risk assessment results were below the threshold limit, although the fish samples contained heavy metals, with values exceeding the permitted limits of Fe (4.41–1604 mg/kg), Cr (727–4155 µg/kg), Zn (4.72–147 mg/kg), and Ni (333–2194 µg/kg). The studied surface waters are characterized by low and high degrees of pollution with heavy metals, as indicated by the heavy metal pollution index scores (HPI: 12.4–86.4) and the heavy metal evaluation index scores (HEI: 1.06–17.6). The considerable pollution levels are attributed to the high Mn content (0.61–49.7 µg/kg), which exceeded the limit up to fifty times. A consistent set of physico-chemical analysis (pH, electrical conductivity, total hardness, turbidity, chloride, sulphate, nitrate, nitrite, ammonium, Ca, Mg, Na, K) was analysed in water samples as well. Considering the water quality index scores (WQI: 16.0–25.2), the surface waters exhibited good quality. Microbiological results indicated the presence of Listeria monocytogenes and atypical colonies of coagulase-positive staphylococcus in fish. In contrast, the surface waters from which fish samples were collected were positive for Escherichia coli, and coliform bacteria intestinal Enterococci. Based on the study’s results, it is recommended to exercise caution in the case of children related to the consumption of fish and using the waters for drinking purposes. This study provides important data of considerable novelty to the riparian population, researchers, and even policy makers on the quality status and potential levels of contamination of river waters, fish and the bioaccumulation of heavy metals in fish that may cause adverse effects on human health if consumed, and similarly the heavy metal pollution degree of waters and the non-carcinogenic risk of heavy metals through ingestion and skin absorption of water in children and adults (the study area is a significant source of fisheries).

Elemental Impurities in Gelatine Capsules: Human Health Risk Assessment

INTRODUCTION. This work continues the authors’ earlier study on gelatine capsule contamination with elemental impurities, which resulted in proposing a list of elements for standardisation. To ensure the safe use of medicinal products in this dosage form, it is necessary to develop criteria for the quantitative assessment of potential human health risks associated with elemental impurities in gelatine capsule shells.AIM. This study aimed to determine the permitted daily concentration (PDC) limits for elemental impurities in gelatine capsules from a risk-based pharmaceutical quality control perspective.MATERIALS AND METHODS. The authors analysed their previous experimental data, the relevant Russian State Standard (GOST), the requirements of the State Pharmacopoeia of the Russian Federation and leading world pharmacopoeias (USA, UK, EU, China, Japan, and India), and the scientific literature published from 1980 to 2023 on the content of elemental impurities (Al, As, Cd, Cu, Cr, Cr, Fe, Hg, Mn, Pb, and Zn) in gelatine capsule shells and medical gelatine.RESULTS. When standardising the content of elemental impurities in gelatine capsule shells, it is necessary to consider not only the toxicity of impurities but also their potential to compromise the quality of gelatine. Complexing elements (Cd, Cu, Hg, Cr, and Zn) can affect the quality of gelatine at subtoxic concentrations. For Cd, Cu, and Hg, the authors recommended using the PDC limits specified in GOST 23058-89 Gelatine. Raw materials for the medical industry. Specifications. For Cr and Zn, the authors recommended adhering to the PDC limits specified in the State Pharmacopoeia of the Russian Federation, edition XIV, Monograph 2.1.0099.18 Gelatine. Lead affects the quality of gelatine at concentrations above the toxicity threshold, and arsenic does not cause clustering of gelatine molecules. For Pb and As, the authors recommended using the PDC limits specified in the State Pharmacopoeia of the Russian Federation, edition XV, General Monograph 1.1.0040 Elemental impurities. The authors proposed a conversion factor to account for the complexing potential of Al when limiting its content in gelatine capsule shells. The authors recommended assessing the risks to human health associated with Mn intake with gelatine capsule shells indirectly by listing total heavy metals as a quality attribute to be controlled at the level of medical gelatine. The content of Fe should also be standardised at the raw material level.CONCLUSIONS. The content of elemental impurities in gelatine capsule shells should not exceed the following limits: 45 µg/g for Al, 1.5 µg/g for As, 0.03 µg/g for Cd, 10 µg/g for Cr, 15 µg/g for Cu, 0.05 µg/g for Hg, 0.5 µg/g for Pb, and 30 µg/g for Zn. The standardisation of these elements in gelatine capsule shells will prevent negative effects on the human body and shell quality.

A review of Health Canada’s progress on human biomonitoring-based risk assessments and the path forward

Since the launch of the Chemicals Management Plan (CMP) in 2006, Health Canada has initiated screening-level risk assessments (RAs) of approximately 4300 priority substances under the Canadian Environmental Protection Act, 1999 (CEPA). With the availability of nationally representative human biomonitoring (HBM) data, over 300 of these substances were assessed using HBM-based RA approaches. Qualitative and quantitative HBM-based RA approaches for the regulatory risk assessment of the general population of Canada were developed to increase the efficiency of screening the potential health risk of CMP priority substances. To support HBM-based RAs, several biomonitoring equivalents (BE) were derived to interpret HBM data. For some CMP substances, Health Canada conducted cumulative risk assessments of chemical mixtures using HBM data as measures of exposure. In 2023, CEPA was amended to include the assessment of populations who may be disproportionately impacted (vulnerable populations) and the cumulative effects of multiple chemicals. Going forward, Health Canada is exploring modern approaches in HBM-based RAs, including biomarkers of effect and non-traditional biomarkers (e.g., hair, nails) to address CEPA amendments. This manuscript will discuss Health Canada’s progress in HBM-based RAs, and the possible path forward in using HBM data to strengthen human health risk assessments.

Calculation the Excess Lifetime Lung Cancer Risk and Human Health Risk Assessment by Inhalation of Radon Gas in the Health Centers of Al–Hay City in Wasit, Iraq Using LR-115 Detector

In this paper, the technology used to measure radon concentrations in 8 health centers of Al- Hay city in Wasit, Iraq (December 2019) is one of the types of solid state nuclear track detectors, LR-115. After that, the annual effective dose rate and the excess lifetime cancer risk were calculated for the selected positions in the study area. The detectors were exposed to radon for 45 days, the etched detectors, using an optical microscope, to calculate the track densities, essentially depend on the alpha ray emitted from radon which later on easy converted to radon concentration values. Radon concentration ranges are from (183.47±22.93 to 17.15±2.14) Bq/m3 with a mean of (100.483Bq/m3), which lower than the appropriate radon levels recommended by ICRP "International Commission on Radiological Protection". The readings of "Excess Lifetime Cancer Risk" (ELCR), which ranges from 3.9 ×10-3 to 8.05 ×10-3 with an average value of 0.53% showing that human health is not under risk even it does not develop any lung cancer while human inhale the radon.

Human health risk assessment of heavy metals in vegetables of Bangladesh

This study aims to evaluate the heavy metal concentration in fifteen species of vegetables as well as associated health risk. Atomic absorption spectrometry is used to assess heavy metals. The mean concentrations of Pb, Cd, Cr, Ni and Fe in vegetables were 4.78, 0.713, 9.266, 0.083, 5.06 mg/kg/fw exceeding the reference value of FAO/WHO indicating unsafe to consumption. Based on principal component analysis, the Pb, Cr, Ni and Fe are from same sources. Health risk was estimated in terms of estimated daily intake (EDI), target hazard quotient, hazard index (HI) and cancer risk (CR). The EDI values of metals except Cr were found to be lower than maximum tolerable daily intake (MTDI). The total THQs of metals were > 1 indicating non-carcinogenic health risk. The individual HI values for vegetables except potato (0.831) and total HI values were found to be > 1 (94.747). The TCR of Pb, Cd and Cr were > 1.0E−04 which indicating carcinogenic risk. Fruit and pod vegetables contribute much in carcinogenic risk for Pb and Cr whereas fruit, root and stems vegetables for Cd. The study revealed potential human health risk associated with the consumption of different types of vegetables in Bangladeshi adult population that might assist the regulatory bodies to develop new strategies to minimize the risk to human.

Occurrence, accumulation, ecological risk, and source identification of potentially toxic elements in multimedia in a subtropical bay, Southeast China

Potentially toxic elements (PTEs) in seawater and sediments may be amplified along the aquatic food chain, posing a health threat to humans. This study comprehensively analyzed the concentrations, distribution, potential sources, and health risk of 7 PTEs in multimedia (seawater, sediment and organism) in typical subtropical bays in southern China. The results indicated that Zn was the most abundant element in seawater, and the average concentration of Cd in sediment was 3.93 times higher than the background value. Except for As, the seasonal differences in surface seawater were not significant. The content of Zn in fishes, crustacea, and shellfish was the highest, while the contents of Hg and Cd were relatively low. Bioaccumulation factor indicated that Zn was a strongly bioaccumulated element in seawater, while Cd was more highly enriched by aquatic organisms in sediment. According to principal component analysis (PCA), and positive matrix factorization (PMF), the main sources of PTEs in Quanzhou Bay were of natural derivation, industrial sewage discharge, and agricultural inputs, each contributing 40.4 %, 24.2 %, and 35.4 %, respectively. This study provides fundamental and significant information for the prevention of PTEs contamination in subtropical bays, the promotion of ecological safety, and the assessment of human health risk from PTEs in seafood.

Nano-enabled strategies to promote safe crop production in heavy metal(loid)-contaminated soil

Nanobiotechnology is a potentially safe and sustainable strategy for both agricultural production and soil remediation, yet the potential of nanomaterials (NMs) application to remediate heavy metal(loid)-contaminated soils is still unclear. A meta-analysis with approximately 6000 observations was conducted to quantify the effects of NMs on safe crop production in soils contaminated with heavy metal(loid) (HM), and a machine learning approach was used to identify the major contributing features. Applying NMs can elevate the crop shoot (18.2 %, 15.4–21.2 %) and grain biomass (30.7 %, 26.9–34.9 %), and decrease the shoot and grain HM concentration by 31.8 % (28.9–34.5 %) and 46.8 % (43.7–49.8 %), respectively. Iron-NMs showed a greater potential to inhibit crop HM uptake compared to other types of NMs. Our result further demonstrates that NMs application substantially reduces the potential health risk of HM in crop grains by human health risk assessment. The NMs-induced reduction in HM accumulation was associated with decreasing HM bioavailability, as well as increased soil pH and organic matter. A random forest model demonstrates that soil pH and total HM concentration are the two significant features affecting shoot HM accumulation. This analysis of the literature highlights the significant potential of NMs application in promoting safe agricultural production in HM-contaminated agricultural lands.

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.

HERisk and statistical clustering integrated for health risk modelling of PTEs in natural water resources for drinking and sanitary uses

Potentially toxic elements (PTEs) are well-known for exposing living organisms and humans to different levels of risk. The present study aimed to evaluate the extent of exposure to health risks sustained by the inhabitants of different suburbs across Southeastern Nigeria as a result of contaminated water sources. There are existing literatures on human health risk assessment in the study region. However, this is the first study to report a detailed breakdown of the risks faced by nine age groups in the study area. This was achieved by integrating a novel code (HERisk), statistical clustering, and water quality data. Laboratory analysis showed that the levels of PTEs (Fe2+, Ni2+, Cr3+, and Pb2+) in 53.6%, 17.8%, 3.5%, and 46% of the samples were found to be above the recommended limits. Aggregated human health risk scores for ingestion and dermal routes revealed that children aged 1 to 2 years are the most vulnerable to health hazards. According to cumulative carcinogenic health risk values (0.00E+00 to 2.41E-04), samples proximal to regions with significant human activities expose the locals to a high risk of developing cancer via ingestion. Q-mode hierarchical cluster analysis successfully validated the classification schemes used for the interpretation of the HERisk code values, captured the patterns in the dataset, and brought forth new perspectives. The comprehensive approach detailed in this study can be adopted as a framework for ongoing monitoring and assessment of water quality.