Search Results (1,799)

Decades of unregulated zinc mining activities in the Mae Tao watershed, located in Mae Sot District, Tak Province, northern Thailand, have resulted in the pervasive contamination of agricultural soils with heavy metals, particularly cadmium (Cd), zinc (Zn), lead (Pb), and manganese (Mn). This legacy pollution has significantly impacted multiple environmental compartments—including surface water, groundwater, and sediments—and poses chronic health risks to local populations. This study investigates the key geochemical and physicochemical factors governing the leachability and mobility of these metals from contaminated soils and evaluates the associated human health risks. Controlled leaching experiments demonstrated that ionic strength exerts a more pronounced influence on metal mobilization than pH or other tested variables, suggesting that the electrolyte composition of pore water plays a dominant role in heavy metal transport. Despite elevated total concentrations of Cd, Zn, Pb, and Mn in the soils, hazard quotient (HQ) calculations indicated no significant non-carcinogenic risk under typical exposure scenarios. However, Cd exhibited a carcinogenic risk above the acceptable threshold at both average and peak soil concentrations, underscoring its potential to adversely affect human health. These findings enhance the understanding of heavy metal behavior in contaminated agroecosystems and provide a scientific basis for targeted risk management and long-term monitoring strategies in the Mae Sot region. Full article

To address the research gap on water-soluble heavy metals (WSHMs) in Taiyuan, China, we conducted a winter campaign (18–29 January 2019) at an urban site to measure fifteen WSHMs (Zn, Fe, Mn, Ba, Cu, Se, As, Sb, Sn, Pb, Ni, V, Ti, Cd, and Co). The mean concentration of total WSHMs (∑WSHMs) in PM_2.5 was 209.17 ± 187.21 ng m⁻³. Notably, the mass concentrations of ∑WSHMs on heavy pollution days (291.01 ± 170.64 ng m⁻³) were 224.8% higher than those on mild pollution days (89.61 ± 55.36 ng m⁻³). Principal component analysis (PCA) was applied in combination with absolute principal component score–multiple linear regression (APCS-MLR) to analyze pollution sources and their contributions. The results showed that the main sources of pollution were coal combustion and vehicle emissions (42.50%), along with the metallurgical industry and natural dust (34.47%). The carcinogenic and non-carcinogenic risks of WSHMs were assessed for both adults and children based on the United States Environmental Protection Agency’s (U.S. EPA) assessment guidelines and the International Agency for Research on Cancer (IARC) database. Children faced higher non-carcinogenic risks (hazard index = 2.37) than adults (hazard index = 0.30), exceeding the safety threshold (hazard index = 1). The total carcinogenic risk reached 2.20 × 10⁻⁵, exceeding the threshold value (1 × 10⁻⁶) for carcinogenic risk. Water-soluble arsenic (As) dominated both carcinogenic and non-carcinogenic risks in winter and was the riskiest element. These findings provide an essential basis for controlling PM_2.5-bound WSHMs in industrialized areas. Full article

Benzene, a well-established human carcinogen and major industrial pollutant, poses significant health risks through occupational exposure due to its no-threshold effect, leading to multi-system damage involving the hematopoietic, nervous, and immune systems. This makes the investigation of its toxic mechanisms crucial for precise prevention and control of its health impacts. Programmed cell death (PCD), an orderly and regulated form of cellular demise controlled by specific intracellular genes in response to various stimuli, has emerged as a key pathway where dysfunction may underlie benzene-induced toxicity. This review systematically integrates evidence linking benzene toxicity to PCD dysregulation, revealing that benzene and its metabolites induce abnormal subtypes of PCD (apoptosis, autophagy, ferroptosis) in hematopoietic cells. This occurs through mechanisms including activation of Caspase pathways, regulation of long non-coding RNAs, and epigenetic modifications, with recent research highlighting the IRP1-DHODH-ALOX12 ferroptosis axis and oxidative stress–epigenetic interactions as pivotal. Additionally, this review describes a comprehensive monitoring system for early toxic effects comprising benzene exposure biomarkers (urinary t,t-muconic acid (t,t-MA), S-phenylmercapturic acid (S-PMA)), PCD-related molecules (Caspase-3, let-7e-5p, ACSL1), oxidative stress indicators (8-OHdG), and genetic damage markers (micronuclei, p14ARF methylation), with correlative analyses between PCD mechanisms and benzene toxicity elaborated to underscore their integrative roles in risk assessment. Furthermore, the review details analytical techniques for these biomarkers, including direct benzene detection methods—direct headspace gas chromatography with flame ionization detection (DHGC-FID), liquid chromatography-tandem mass spectrometry (LC-MS/MS), and portable headspace sampling (Portable HS)—alongside molecular imprinting and fluorescence probe technologies, as well as methodologies for toxic effect markers such as live-cell imaging, electrochemical techniques, methylation-specific PCR (MSP), and Western blotting, providing technical frameworks for mechanistic studies and translational applications. By synthesizing current evidence and mechanistic insights, this work offers novel perspectives on benzene toxicity through the PCD lens, identifies potential therapeutic targets associated with PCD dysregulation, and ultimately establishes a theoretical foundation for developing interventional strategies against benzene-induced toxicity while emphasizing the translational value of mechanistic research in occupational and environmental health. Full article

Aflatoxins (AFs), harmful secondary metabolites produced by the genus Aspergillus, particularly Aspergillus flavus and Aspergillus parasiticus, are one of the best-known potent mycotoxins, posing a significant risk to public health. The primary type, especially aflatoxin B₁ (AFB₁), is a potent carcinogen associated with liver cancer, immunosuppression, and other health problems. Environmental factors such as high temperatures, humidity, and inadequate storage conditions promote the formation of aflatoxin in staple foods such as maize, peanuts, and rice. Immunocompromised individuals, including those with HIV/AIDS, hepatitis, cancer, or diabetes, are at increased risk due to their reduced detoxification capacity and weakened immune defenses. Chronic exposure to AF in these populations exacerbates liver damage, infection rates, and disease progression, particularly in developing countries and moderate-income populations where food safety regulations are inadequate and reliance on contaminated staple foods is widespread. Biomarkers such as aflatoxin-albumin complexes, urinary aflatoxin M₁, and aflatoxin (AF) DNA adducts provide valuable insights but remain underutilized in resource-limited settings. Despite the globally recognized health risk posed by AF, research focused on monitoring human exposure remains limited, particularly among immunocompromised individuals. This dynamic emphasizes the need for targeted studies and interventions to address the particular risks faced by immunocompromised individuals. This review provides an up-to-date overview of AF exposure in immunocompromised populations, including individuals with cancer, hepatitis, diabetes, malnutrition, pregnant women, and the elderly. It also highlights exposure pathways, biomarkers, and biomonitoring strategies, while emphasizing the need for targeted interventions, advanced diagnostics, and policy frameworks to mitigate health risks in these vulnerable groups. Addressing these gaps is crucial to reducing the health burden and developing public health strategies in high-risk regions. Full article

A total of 162 groundwater samples were collected during November and December 2022 in the Xin’an River Basin during the dry season. In this research, the concentrations of various indicators in most samples did not exceed the prescribed standards. The indicators with the largest number of exceedances were iodine and manganese, with 22 and 23 samples, respectively. Overall, the groundwater quality in the Xin’an River Basin was generally good, with only 7 samples with the EWQI values greater than 150, which exhibited poor groundwater quality. The primary factors influencing groundwater quality were the concentrations of I, Mn, and Al, which were predominantly affected by water–rock interactions. Groundwater quality in the Xin’an River Basin was mainly influenced by natural factors rather than anthropogenic activities. Both the carcinogenic and non-carcinogenic health risks posed by groundwater in the Xin’an River Basin were higher for children than for adults. The long-term chronic cumulative effect was the most important factor contributing to both carcinogenic and non-carcinogenic health risks. Iodine presented the highest non-carcinogenic health risks for both adults and children. In regions where high-iodine groundwater was distributed, it is recommended to enhance the monitoring of iodine concentrations in the groundwater. Full article

Groundwater quality in arid and semi-arid regions of Morocco is under increasing pressure due to both anthropogenic influences and climatic variability. This study investigates the physicochemical and heavy metal characteristics of groundwater across four Moroccan regions (Tangier-Tetouan-Al Hoceima, Oriental, Souss-Massa, and Marrakech-Safi) known for being argan tree habitats. Thirteen groundwater samples were analyzed for twenty-five parameters, including major ions, nutrients, and trace metals. Elevated levels of ammonium, turbidity, electrical conductivity, and dissolved oxygen were observed in multiple samples, surpassing Moroccan water quality standards and indicating significant quality deterioration. Inductively Coupled Plasma-Atomic Emission Spectroscopy (ICP-AES) detected arsenic concentrations exceeding permissible limits in sample AW11 alongside widespread lead contamination in most samples except AW5 and AW9. Spatial patterns of contamination were characterized using Principal Component Analysis (PCA), Hierarchical Cluster Analysis (HCA), K-means clustering, and GIS-based Inverse Distance Weighted (IDW) interpolation. These multivariate approaches revealed marked spatial heterogeneity and highlighted the dual influence of geogenic processes and anthropogenic activities on groundwater quality. To assess consumption suitability, a Water Quality Index (WQI) and Human Health Risk Assessment were applied. As a result, 31% of samples were rated “Fair” and 69% as “Good”, but with notable non-carcinogenic risks, particularly to children, attributable to nitrate, lead, and arsenic. The findings underscore the urgent need for systematic groundwater monitoring and management strategies to safeguard water resources in Morocco’s vulnerable dryland ecosystems, particularly in regions where groundwater sustains vital socio-ecological species such as argan forests. Full article

Plastics have become integral to modern life; however, their widespread use and persistent nature have resulted in significant environmental contamination, especially by microplastics (MPs < 5 mm) and nanoplastics (NPs < 100 nm). These plastic particles can enter the human body via ingestion, inhalation, or dermal absorption, raising substantial concerns about their potential health impacts. Recent studies using zebrafish, rodent models, and human cell lines have begun to elucidate the mechanisms underlying micro- and nanoplastics (MNPs)-induced toxicity. These mechanisms include oxidative stress, inflammation, disruption of metabolic processes, neurotoxicity, reproductive dysfunction, and carcinogenicity. Despite these advances, significant knowledge gaps remain. There remains a lack of comprehensive reviews that systematically evaluate these effects across major human organ systems and address how MNPs cross biological barriers in the human body. This review addresses these gaps by summarizing the available evidence on MNPs’ toxicity, critically discussing their absorption, distribution, metabolism, and the associated cellular and molecular mechanisms of action. Furthermore, it outlines urgent research priorities, emphasizing the need for standardized analytical protocols, realistic exposure models, and extended epidemiological research to evaluate human health risks posed by MNPs accurately. In addition, the adoption of precautionary regulatory actions is recommended to mitigate exposure and safeguard public health. Full article

Breast milk is the ideal source of nutrition for infant growth and development. However, when nursing mothers consume aflatoxin B₁ (AFB₁)-contaminated food, the hydroxylated form aflatoxin M₁ (AFM₁) is transferred to breast milk and urine. AFB₁ and its metabolite AFM₁ are potent carcinogens and can pose significant risks to food safety and public health worldwide. This study determined the prevalence of AFM₁ in the breast milk and urine of nursing mothers in Bangladesh and estimated infant exposure to this toxin. Breast milk and urine samples (72 each), collected from nursing mothers in three different regions of the country, were analyzed for AFM₁ occurrence via a sensitive enzyme-linked immunosorbent assay (ELISA). AFM₁ was present in 88.9% of urine samples, with a mean concentration of 109.9 ± 52.8 pg/mL, ranging from 40.0 to 223.8 pg/mL. AFM₁ was also detected in 50% of the breast milk samples, with a mean concentration of 4.6 ± 0.7 pg/mL, ranging from 4.0 to 6.1 pg/mL. A strong correlation (r = 0.72) was observed between milk and urinary AFM₁ levels, indicating these as suitable biomarkers of AFB₁ exposure. Yet, no significant correlations were identified between AFM₁ levels in either milk or urine and the food items typically consumed by nursing mothers. The average estimated daily intake (EDI) for AFM₁ with breast milk was 0.59 ng/kg bw/day, with no significant difference between infants (0.57 ng/kg bw/day) and toddlers (0.65 ng/kg bw/day). A comparison of computed EDI ranges for AFM₁ with a proposed tolerable daily intake value resulted in Hazard Indices below 1 for all exposure scenarios. This indicates that the AFM₁ concentrations in breast milk from three regions of Bangladesh raise no concern. Also, the measured levels were far lower than the maximal levels set in the EU regulations for AFM₁ in dairy milk and infant formula (50 ng/kg and 25 ng/kg, respectively). Full article

Excessive alcohol consumption is associated with systemic health risks due to the production of acetaldehyde, a primary carcinogen that not only pollutes the environment but also endangers human health. In this study, a promising bacterial strain for biodegrading both ethanol and acetaldehyde was successfully isolated from the traditional fermented food Jiaosu and identified as Acetobacter ghanensis JN01 based on average nucleotide identity (ANI) analysis. Initial ethanol of 1 g/L was completely biodegraded within 4 h, while initial acetaldehyde of 1 g/L was also rapidly removed at 2 or 1 h by whole cells or cell-free extracts (CEs) of JN01, respectively, which indicated that JN01 indeed has a strong ability in the biodegradation of both ethanol and acetaldehyde. Whole-genome sequencing revealed a 2.85 Mb draft genome of JN01 with 57.0% guanine–cytosine (GC) content and the key metabolic genes (adh1, adh2, and aldh) encoding involving alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), co-located with NADH dehydrogenase genes and ethanol-responsive regulatory motifs, supporting the metabolic pathway of transforming ethanol to acetaldehyde, and, subsequently, converting acetaldehyde to acetic acid. Furthermore, selected in vitro safety-related traits of JN01 were also assessed, which is very important in the development of microbial catalysts against both ethanol and acetaldehyde. Full article

This study investigates the presence, origin, and associated ecological and human health risks of polycyclic aromatic hydrocarbons (PAHs) in soils from uncultivated lands and beach sediments within the Yellow River Delta (YRD), China. The measured concentrations of 16 priority PAHs in soils spanned 24.97–326.42 ng/g (mean: 130.88 ng/g), while concentrations in sediments ranged from 46.17 to 794.32 ng/g, averaging 227.22 ng/g. In terms of composition, low-molecular-weight PAHs predominated in soil samples, whereas high-molecular-weight compounds were more prevalent in sediments. The positive matrix factorization (PMF) model results suggested that petroleum pollution and fuel combustion were the main sources of PAHs in soils, whereas the contribution in sediments was derived from petroleum and traffic pollution. The ecological risk assessment results indicated that there existed no obvious ecological risk of soil PAHs, but sediment PAHs could negatively impact the surrounding ecological environment, especially in the northern coastal beach area. In addition, soil PAHs posed no potential carcinogenic risk to humans. Further pollution prevention and management measures are required in this region to ensure the safety of the environment. Full article

Air pollution is linked to childhood mortality and morbidity in low- and middle-income countries globally. There is growing evidence linking air pollution to asthma and other respiratory diseases in children. Studies have shown that children are likely to experience asthma due to their narrow airways and their heightened sensitivity to environmental irritants. This study aims to investigate the relationship between ambient air pollution and respiratory diseases in children under the age of 5. The study will be conducted in the informal township of Alexandra, north of Johannesburg, South Africa. A quantitative approach will be used in this cross-sectional analytical study. Data will be collected using different tools that include a questionnaire to determine the prevalence of asthma and respiratory disease and potential risk factors. While environmental air pollution will be measured using Radiello passive samplers and Gillian pumps. Data will be analyzed using the latest version of the STATANow/MP 19.5 software. Furthermore, health risk assessment will be conducted for lifetime non-carcinogenic and carcinogenic risk estimation following the USEPA framework. The study will identify environmental triggers that exacerbate asthma and other respiratory conditions in other similar community settings and will contribute to the body of knowledge in public health. Ethical approval was obtained from the Research Ethics Committee, Faculty of Health Sciences at the University of Johannesburg. Full article

Background/Objectives: Acrylamide is a probably carcinogenic to humans that naturally forms during the thermal processing of foods. An individual’s lifestyle—especially dietary habits and physical activity—may influence the severity of acrylamide’s adverse health effects. This study aimed to examine the relationship between adolescents’ dietary and exercise behaviors and their dietary acrylamide exposure and associated health risks. Methods: This descriptive and cross-sectional study was conducted with 370 high school students in Türkiye. Data were collected using the Nutrition Exercise Behavior Scale (NEBS) and a retrospective 24-h dietary recall questionnaire. Acrylamide exposure was calculated based on food intake to estimate carcinogenic (CR) and non-corcinogenic (target hazard quotient: THQ) health risks and analyzed in relation to NEBS scores. Results: Findings indicated that while adolescents are beginning to adopt healthy eating and exercise habits, these behaviors are not yet consistent. Emotional eating and unhealthy food choices still occur. Higher acrylamide exposure and risk values were observed in boys and underweight individuals. This can be explained mainly by the fact that boys consume more of certain foods—especially bread, which contains relatively higher levels of acrylamide—than girls do, and that underweight individuals have lower body weights despite consuming similar amounts of food as other groups. Bread products emerged as the primary source of daily acrylamide intake. Positive correlations were found between NEBS total and subscale scores and acrylamide exposure and health risk values. Conclusions: The study demonstrates a significant association between adolescents’ health behaviors and acrylamide exposure. These results underscore potential public health concerns regarding acrylamide intake during adolescence and emphasize the need for targeted nutritional interventions to reduce risk and promote sustainable healthy behaviors. Full article

Seafood contamination by heavy metals is a growing public health concern, particularly in regions like Tunisia where seafood is a major dietary component. This study assessed concentrations of cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in the muscle tissue of the red shrimp Parapenaeus longirostris, collected in 2023 from four coastal regions: Bizerte, Monastir, Kerkennah, and Gabes. Metal analysis was conducted using flame atomic absorption spectroscopy. This species was chosen due to its ecological and economic importance. The study sites were chosen based on their differing levels of industrial, urban, and agricultural influence, providing a representative overview of regional contamination patterns. Mean concentrations were 1.04 µg/g for Zn, 0.59 µg/g for Cu, 1.56 µg/g for Pb, and 0.21 µg/g for Cd (dry weight). Pb was the most prevalent metal across sites. Statistically significant variation was observed only for Cu (p = 0.0334). All metal concentrations were below international safety limits set by FAO/WHO and the European Union. Compared to similar studies, the levels reported were similar or slightly lower. Human health risk was evaluated using target hazard quotient (THQ), hazard index (HI), and cancer risk (CR) values. For adults, THQ ranged from 5.44 × 10⁻⁶ to 8.43 × 10⁻⁴, while for children it ranged from 2.40 × 10⁻⁵ to 3.72 × 10⁻³. HI values were also well below 1, indicating negligible non-carcinogenic risk. CR values for Cd and Pb in both adults and children fell within the acceptable risk range (10⁻⁶ to <10⁻⁴), suggesting no significant carcinogenic concern. This study provides the first field-based dataset on metal contamination in P. longirostris from Tunisia, contributing valuable insights for seafood safety monitoring and public health protection. Full article

Potentially toxic elements, such as chromium (Cr) and zinc (Zn), play essential roles in humans and animals. However, the harmful effects of excessive exposure to these elements through food remain unknown. In this sense, this study aimed to evaluate the anthropogenic contamination of chromium and zinc in aquatic biota and seafood consumers. Based on the PRISMA protocol, 67 articles were selected for this systematic review. The main results point to a wide distribution of these elements, which have familiar emission sources in the aquatic environment, especially in highly industrialized regions. Significant concentrations of both have been reported in different fish species, which sometimes represent a non-carcinogenic risk to consumer health and a carcinogenic risk related to Cr exposure. New studies should be encouraged to fill gaps, such as the characterization of the toxicity of these essential elements through fish consumption, determination of limit concentrations updated by international regulatory institutions, especially for zinc, studies on the influence of abiotic factors on the toxicity and bioavailability of elements in the environment, and those that evaluate the bioaccessibility of these elements in a simulated digestion system when in high concentrations. Full article

Per- and polyfluoroalkyl substances (PFASs) have gained significant attention due to their widespread distribution in the environment and potential adverse health effects. While ingestion, especially through contaminated drinking water, is considered the primary route of human exposure, recent research suggests that other pathways, such as inhalation and dermal absorption, also play a significant role. This review provides a concise overview of the toxicological impacts of both legacy and emerging PFASs, such as GenX and perfluorobutane sulfonic acid (PFBS), with a particular focus on their effects on the liver, kidneys, and immune and nervous systems, based on findings from recent in vivo, in vitro, and epidemiological studies. Despite the transition to PFAS alternatives, much of the existing toxicity data focus on a few legacy compounds, such as perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), which have been linked to adverse immune outcomes, particularly in children. However, evidence for carcinogenic risk remains limited to populations with extremely high exposure levels, and data on neurodevelopmental effects remain underexplored. While epidemiological and experimental animal studies supported these findings, significant knowledge gaps persist, especially regarding emerging PFASs. Therefore, this review examines the visceral, neural, and immunotoxicity data for emerging PFASs and mixtures from recent studies. Given the known risks from well-studied PFASs, a precautionary principle should be adopted to mitigate human health risks posed by this large and diverse group of chemicals. Full article