Evidence on the relationship between lifestyle, socio-economic factors and pesticide exposure and urinary concentrations of organophosphate (OP) pesticide metabolites among children is generally incomplete. This study investigated the relationship between socio-economic factors and reported pesticide exposures and the sum of three urinary concentrations of dialkyl phosphate metabolites (DAP) among boys living in the rural areas of the Western Cape, South Africa. Data was collected during a cross-sectional study of 183 boys from three agricultural intense areas. Measurements included a questionnaire on socio-economic and pesticide exposures and urinary DAP concentrations. Most boys (70%) lived on farms with a median age of 12 years (range: 5.0–19.5 years). Children aged >14 years had lower DAP urine concentrations (median = 39.9 ng/ml; β = −68.1 ng/ml; 95% CI: −136.8, 0.6) than children aged 9 years and younger (median = 107.0 ng/ml). DAP concentrations also varied significantly with area, with concentrations in the grape farming area, Hex River Valley (median = 61.8 ng/ml; β = −52.1; 95% CI: −97.9, −6.3 ng/ml) and the wheat farming area, Piketberg (median = 72.4 ng/ml; β = −54.2; 95% CI: 98.8, −9.7 ng/ml) lower than those in the pome farming area, Grabouw (median = 79.9 ng/ml). Other weaker and non-significant associations with increased DAP levels were found with increased household income, member of household working with pesticides, living on a farm, drinking water from an open water source and eating crops from the vineyard and or garden. The study found younger age and living in and around apple and grape farms to be associated with increased urinary DAP concentrations. Additionally, there were other pesticide exposures and socio-economic and lifestyle factors that were weakly associated with elevated urinary DAP levels requiring further study. The study provided more evidence on factors associated to urinary DAP concentrations especially in developing country settings.

The effect of prenatal exposure to perfluoroalkyl substances (PFAS) on lipid concentrations in newborns is unknown. Using data from the Shanghai-Minhang Birth Cohort Study, we prospectively assessed the health effects of prenatal exposure to individual and multiple PFAS on cord lipid concentrations. Maternal plasma samples collected at 12–16 weeks of gestation were analyzed for eleven PFAS, and cord blood samples were analyzed for lipids: total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C). We used multiple linear regression models to evaluate the associations of each individual PFAS with each lipid parameter, and used Bayesian Kernel Machine Regression (BKMR) models to assess the overall and single-exposure effects of eight PFAS with the detection rate above 80% on cord lipid concentrations. In multiple linear regression models, for each unit increase in ln-transformed maternal concentrations of perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUdA), and perfluorotridecanoic acid (PFTrDA), ln-transformed TC concentration decreased by 0.15 mg/dL (95% confidence interval (CI): −0.25, −0.05), 0.12 mg/dL (95% CI: −0.19, −0.05), 0.12 mg/dL (95% CI: −0.19, −0.05), and 0.05 mg/dL (95% CI: −0.09, −0.01), respectively, and ln-transformed HDL-C concentration decreased by 0.17 mg/dL (95% CI: −0.29, −0.05), 0.12 mg/dL (95% CI: −0.20, −0.03), 0.12 mg/dL (95% CI: −0.20, −0.03), and 0.06 mg/dL (95% CI: −0.11, −0.00), respectively. Statistically significant inverse associations were also observed between ln-transformed concentrations of PFDA, PFUdA, or PFTrDA and ln-transformed cord concentrations of TG and LDL-C. In BKMR models, the mixture of eight PFAS showed suggestively inverse association with all ln-transformed lipid concentrations, such that ln-transformed TC concentration of exposure to the 75th percentile of the mixture was 0.11 units (95% credible interval, −0.21, −0.01) lower than the 25th percentile exposure. Our findings indicated that prenatal exposure to PFAS may disrupt lipid metabolism in newborns.

Triclosan (TCS), an emergent pollutant, is raising a global concern due to its toxic effects on organisms and aquatic ecosystems. The non-availability of proven treatment technologies for TCS remediation is the central issue stressing thorough research on understanding the underlying mechanisms of toxicity and assessing vital biomarkers in the aquatic organism for practical monitoring purposes. Given the unprecedented circumstances during COVID 19 pandemic, a several-fold higher discharge of TCS in the aquatic ecosystems cannot be considered a remote possibility. Therefore, identifying potential biomarkers for assessing chronic effects of TCS are prerequisites for addressing the issues related to its ecological impact and its monitoring in the future. It is the first holistic review on highlighting the biomarkers of TCS toxicity based on a comprehensive review of available literature about the biomarkers related to cytotoxicity, genotoxicity, hematological, alterations of gene expression, and metabolic profiling. This review establishes that biomarkers at the subcellular level such as oxidative stress, lipid peroxidation, neurotoxicity, and metabolic enzymes can be used to evaluate the cytotoxic effect of TCS in future investigations. Micronuclei frequency and % DNA damage proved to be reliable biomarkers for genotoxic effects of TCS in fishes and other aquatic organisms. Alteration of gene expression and metabolic profiling in different organs provides a better insight into mechanisms underlying the biocide's toxicity. In the concluding part of the review, the present status of knowledge about mechanisms of antimicrobial resistance of TCS and its relevance in understanding the toxicity is also discussed referring to the relevant reports on microorganisms.

Fish is an important source of nutritional omega-3 (n-3) polyunsaturated fatty acids, but it also readily accumulates toxic mercury (Hg) and microcystins (MC) in eutrophic aquatic systems. In China, farmed fish was widely consumed, and aquaculture has caused pervasive eutrophication of freshwater lakes, resulting in the increasing accumulation of MC in fish tissue. To assess the risk-benefit of consuming farmed fish, 205 fish samples of 10 primary species were collected from the eutrophic Wujiangdu (WJD) Reservoir, SW China. The contents of Hg, microcystin-RR (MC-RR), microcystin-LR (MC-LR), and polyunsaturated fatty acids (PUFA) in fish were analyzed. The results showed that THg and MeHg concentrations in all fish sampls were well below the safety limit (500 ng/g w.w) established by the Standardization Administration of China, with average values of 22.9 ± 22.8 and 6.0 ± 6.6 ng/g wet weight (w.w.), respectively. Average concentrations of MC-RR and MC-LR were 40 ± 80 and 50 ± 80 ng/g w.w., respectively. MC-RR and MC-LR concentrations in fish were significantly higher in silver carp and black carp than in perch and catfish (p < 0.05). In nutritional terms, average concentrations of n-3 PUFA and the eicosapentaenoic (EPA) + docosahexaenoic acids (DHA) of fish were 2.0 ± 2.5 and 1.4 ± 0.5 mg/g w.w., respectively. The risk-benefit assessment suggests that the n-3 PUFA benefits from consuming all farmed fish species in the WJD Reservoir outweigh the adverse effects of MeHg. However, except for perch, most fish species still pose a high MC-LR exposure risk that created a requirement for fish consumption advisories and monitoring. Consequently, more attention should be paid on the health risk of combined exposure to pollutants by aquatic product consumption.

Biomonitoring of aquatic environments requires new tools to characterize the effects of pollutants on living organisms. Zebra mussels (Dreissena polymorpha) from the same site in north-eastern France were caged for two months, upstream and downstream of three wastewater treatment plants (WWTPs) in the international watershed of the Meuse (Charleville-Mézières “CM” in France, Namur “Nam” and Charleroi “Cr” in Belgium). The aim was to test ¹H-NMR metabolomics for the assessment of water bodies’ quality. The metabolomic approach was combined with a more “classical” one, i.e., the measurement of a range of energy biomarkers: lactate dehydrogenase (LDH), lipase, acid phosphatase (ACP) and amylase activities, condition index (CI), total reserves, electron transport system (ETS) activity and cellular energy allocation (CEA). Five of the eight energy biomarkers were significantly impacted (LDH, ACP, lipase, total reserves and ETS), without a clear pattern between sites (Up and Down) and stations (CM, Nam and Cr). The metabolomic approach revealed variations among the three stations, and also between the upstream and downstream of Nam and CM WWTPs. A total of 28 known metabolites was detected, among which four (lactate, glycine, maltose and glutamate) explained the observed metabolome variations between sites and stations, in accordance with chemical exposure levels. Metabolome changes suggest that zebra mussel exposure to field contamination could alter their osmoregulation and anaerobic metabolism capacities. This study reveals that lactate is a potential biomarker of interest, and ¹H-NMR metabolomics can be an efficient approach to assess the health status of zebra mussels in the biomonitoring of aquatic environments.

Worldwide increasing levels of lead in water systems require the search for efficient ecologically friendly strategies to remove it. Hence, lead accumulation by the free-living algae-like Euglena gracilis and its effects on cellular growth, respiration, photosynthesis, chlorophyll, calcium, and levels of thiol- and phosphate-molecules were analyzed. Photosynthetic cells were able to accumulate 4627 mg lead/kgDW after 5 days of culture with 200 μM Pb²⁺. Nevertheless, exposure to 50, 100 and 200 μM Pb²⁺ for up to 8 days did not modify growth, viability, chlorophyll content and oxygen consumption/production. Enhanced biosynthesis of thiol molecules and polyphosphates, i.e. the two canonical metal ion chelation mechanisms in E. gracilis, was not induced under such conditions. However, in cells cultured in the absence of phosphate, lead accumulation and polyphosphate content markedly decreased, while culturing in the absence of sulfate did not modify the accumulation of this metal. In turn, the total amount of intracellular calcium slightly increased as the amount of intracellular lead increased, whereas under Ca²⁺ deficiency lead accumulation doubled. Therefore, the results indicated that E. gracilis is highly resistant to lead through mechanisms mediated by polyphosphates and Ca²⁺ and can in fact be classified as a lead hyperaccumulator microorganism.

In order to solve the low sorption capacity of pristine biochar for anionic pollutants, e.g., reactive red 120 (RR120), a novel mesoporous Fe-biochar composite was fabricated in this study by combination of Fe-loading and ball-milling methods. The ball-milling Fe-biochar composite could effectively remove RR120 by up to 90.1 mg g⁻¹ at pH of 7.5, and slightly alkaline condition was preferred. Adsorption kinetics showed that ball-milling Fe-biochar composite could quickly sorb RR120 with the rate constant (k₂) of 2.07 g mg⁻¹ min⁻¹ (pH = 7.5). Positive surface charge and large surface area were responsible for the outstanding removal performance of RR120 by ball-milling Fe-biochar composite: (1) The adscititious Fe would be converted to β-FeOOH during pyrolysis, which significantly improved the zeta potential of biochar and thus facilitated the electrostatic adsorption for RR120, which contributed to 42.3% and 85.5% at pH of 3 and 7.5, respectively; (2) Ball-milling effectively increased the specific surface area and uniformed the pore size distribution, which could provide more sorption sites and expedite the diffusion of RR120 molecules, shortening the time from several hours to less than 15 min. Findings of this study not only provide a feasible modification method for biochar to adsorb anionic pollutants efficiently and rapidly, but also help to reveal the roles of Fe-loading and ball-milling in enhancing adsorption capacity.

Certain viruses and parasites can cause persistent infections that often co-occur and have been associated with substantial morbidity and mortality. Separate lines of research indicate exposures to per- and polyfluoroalkyl substances (PFAS) suppress the immune system. We hypothesized that PFAS exposures might systematically increase susceptibility to persistent infections resulting in a higher pathogen burden. We used data from 8778 individuals (3189 adolescents, 5589 adults) in the nationally-representative U.S. National Health and Nutrition Examination Survey (NHANES) 1999–2016 to examine cross-sectional associations between serum concentrations of four highly detected PFAS (PFOS, PFOA, PFHxS, PFNA) with the presence of antibodies to cytomegalovirus, Epstein Barr virus, hepatitis C and E, herpes simplex 1 and 2, HIV, T. gondii, and Toxocara spp. Seropositivity was summed to calculate a pathogen burden score reflecting the total number of infections. Separate survey-weighted multivariable regression models were fitted to analyze PFAS individually and quantile g-computation was used to analyze PFAS mixtures. Among adolescents, 38.7% had at least one persistent infection while 14.9% had two or more; among adults, these percentages were 48.0% and 19.7%. Each PFAS was individually associated with significantly higher pathogen burdens and the most pronounced associations were observed in adolescents [e.g., among adolescents, a doubling of PFOS was associated with 30% (95% CI: 25–36%) higher pathogen burden]. Quantile g-computation revealed PFAS mixtures as a whole were also associated with higher pathogen burdens. Taken together, these results suggest PFAS exposure may increase susceptibility to and foster the clustering of persistent infections, particularly among adolescents. Since persistent infections are important contributors to long-term health, prospective data are needed to confirm these findings.

Extracellular Polymeric Substances (EPS) influenced Poly Cyclic Aromatic Hydrocarbons (PAHs) degrading Klebsiella pneumoniae was isolated from the marine environment. To increase the EPS production by Klebsiella pneumoniae, several physicochemical parameters were tweaked such as different carbon sources (arabinose, glucose, glycerol, lactose, lactic acid, mannitol, sodium acetate, starch, and sucrose at 20 g/L), nitrogen sources (ammonium chloride, ammonium sulphate, glycine, potassium nitrate, protease peptone and urea at 2 g/L), different pH, carbon/nitrogen ratio, temperature, and salt concentration were examined. Maximum EPS growth and biodegradation of Anthracene (74.31%), Acenaphthene (67.28%), Fluorene (62.48%), Naphthalene (57.84%), and mixed PAHs (55.85%) were obtained using optimized conditions such as glucose (10 g/L) as carbon source, potassium nitrate (2 g/L) as the nitrogen source at pH 8, growth temperature of 37 °C, 3% NaCl concentration and 72 h incubation period. The Klebsiella pneumoniae biofilm architecture was studied by confocal laser scanning microscopy (CLSM) and scanning electron microscope (SEM). The present study demonstrates the EPS influenced PAHs degradation of Klebsiella pneumoniae.

Chronic exposure to potassium bromate (KBrO₃), a toxic halogen in the environment, has become a global problem of public health. The current study aims to elucidate for the first time the effect of Urtica dioica (UD) on behavioural changes, oxidative stress, and histopathological changes induced by KBrO₃ in the cerebellum, kidney, liver and other organs of adult rats.The rats were divided into four groups: group 1 served as a control received physiological serum, Group 2 received KBrO₃ (2 g/L of drinking water), group 3 received KBrO₃ and Urtica dioica (100 mg/kg), and group 4 received KBrO₃ and Urtica dioica (400 mg/kg). We then measured behavioural changes, oxidative stress, and biochemical and histological changes in the cerebellum, liver, kidney and others organs in these rats. After 30 days of treatment, the animals were sacrificed.We observed significant behavioural changes in KBrO₃-exposed rats. When investigating redox homeostasis in the cerebellum, we found that mice treated with KBrO₃ had increased lipid peroxidation and protein oxidation in the cerebellum. In addition, it inhibits hepatic and lipid peroxidation (malondialdehyde), advanced oxidation protein product (AOPP), attenuates KBrO₃-mediated enzyme depletion, catalase, superoxide dismutase, glutathione peroxidase enzymatic and antioxidant activities in the liver and kidney. Rats that were co-managed with Urtica dioica at the high portion of 400 mg/kg indicated a higher effect than that treated with the low dose of 100 mg/kg practically in all the tests carried out.Our results demonstrate that Urtica dioica is a potential therapeutic agent for oxidative stress associated with neurodegenerative diseases.