Emerging Contaminants最新文献

Microplastics (MPs) are present throughout the environment, and due to their nature, they are extremely difficult to decompose. Reportedly, microorganisms play an important role in degrading and decomposing MPs. Bacillus pasteurii can degrade various complex organic matter, including MPs, which are a class of polymeric organic compounds. This study investigated the degradation effect of B. pasteurii on polypropylene MPs (PP-MPs) in soil. B. pasteurii was extracted from gold mine tailings. Herein, three experimental groups were established—a blank control treatment group, a group with bacteria without Ca²⁺ added (T2 group), and a group with bacteria supplemented with Ca²⁺ (T3 group)—for a 30-day indoor simulation of MP degradation in MP-treated soil. The results showed that the total mass change rate of the PP-MPs in the T2 group was 20.95 %, and grooves and holes appeared on the PP-MP surfaces. The total mass change rate of the PP-MPs in the T3 group was 23.22 %, and abundant fissures and pits appeared on the PP-MP surfaces. Additionally, new dominant phyla, such as Bacteroidetes and Firmicutes, appeared after bacterial addition. The relative abundance of several common soil genera, such as Bacillus, Brevundimonas, Flavobacterium, and Arthrobacter, and genera capable of breaking down complex compounds increased after B. pasteurii addition. The soil microbial community diversity improved, with the distribution of each species being relatively uniform. These findings indicated that the B. pasteurii strain can be used to degrade PP-MPs. Additionally, the addition of Ca²⁺ generated microbially induced calcium carbonate precipitation, which further improved the degradation of MPs. This study provides theoretical support for studying the degradation mechanism of PP-MPs.

Endosulfan and hexachlorobenzene (HCB) were previously widely used organochlorine pesticides. Much attention has been paid to trends in human exposure to endosulfan and HCB and to the transport and distribution of endosulfan and HCB within the body. We determined endosulfan I, endosulfan II, and HCB concentrations in serum samples collected from the general population of Wuxi in Jiangsu Province (China) between 2012 and 2016. The endosulfan concentrations varied little throughout the study period, but the HCB concentrations increased. The HCB concentrations were significantly higher in serum from overweight people and smokers than in serum from normal weight people (p = 0.028) and non-smokers (p = 0.011), respectively. HCB binds to human serum albumin (HSA) and can form halogen bonds to CYS-461 and ARG-484 at site II (subdomain IIIA). Fatty acids and nicotine increase the affinity between HCB and HSA, explaining the higher HCB concentrations in serum from overweight people and smokers than normal weight people and non-smokers, respectively.

Background

Current epidemiological results from studies linking per- and poly-fluoroalkyl substances (PFASs) to metabolic syndrome (MetS) remain inconsistent.

Objectives

We aim to investigate the association between serum PFASs and MetS using data from the National Health and Nutrition Examination Survey in the United States (US NHANES) 2017–2018.

Methods

The Bayesian kernel regression (BKMR) and weighted quantiles sum regression (WQS) models were used to assess the association of serum PFASs with MetS and calculate the weight of each substance. Stratification analysis and sensitivity analysis were used to study the effect modification and the robustness of the study results, respectively.

Results

All statistical models used in this study consistently indicated that serum perfluorononanoic acid (PFNA) was positively associated with an increased risk of MetS. The BKMR model revealed that serum PFASs mixtures had a combined toxic effect on MetS and its components, and serum PFNA could contribute the most to driving the overall association. Specifically, the combined exposure of PFASs was significantly associated with lipids (LP), among which serum PFNA contributed significantly to high density lipoprotein cholesterol (HDL-C), and serum perfluorodecanoate (PFDeA) was significantly positively correlated with triglyceride (TG). Besides, a nonlinear dose-response relationship between PFASs and MetS was observed. The final stratified analysis results underscore the critical importance of maintaining a healthy lifestyle, as obesity, smoking, and consume carryout/delivered foods exhibit effect modification on the association between PFASs and MetS.

Conclusion

Our findings point to PFNA as a risk factor for metabolic diseases, particularly affecting lipids.

Insecticides play a crucial role in safeguarding crops from pest. However, prior to their release, it is essential to assess the efficacy and potential effects of these protectants. Flupyradifurone (FBF) and sulfoxaflor (SFX), two insecticides commonly used to control aphids, have been found to exert negative effects on the growth and development of Binodoxys communis Gahan, a beneficial parasitic wasp that targets aphids. However, it remains unknown if FBF and SFX influence the symbiotic bacteria residing within B. communis. In this study, 16SrRNA sequencing was utilized to assess the populations of B. communis symbionts exposed to sublethal concentrations (LC₁₀ and LC₂₅) of FBF and SFX. The control and treatment groups exhibited similar bacterial community structures, with Bacteroidota identified as the dominant phylum in each. After exposure to FBF and SFX, the diversity and richness of symbionts (Firmicutes, Bacteroidota, and Actinobacteriota) in B. communis changed notably. The two different insecticides and exposure durations exerted distinct effects on the microbial community. For instance, SFX stress resulted in a decrease in Akkermansia and an increase in Escherichia Shigella 1h after exposure, with both returning to baseline levels after 3d. In contrast, FBF exposure caused a reduction in Akkermansia presence after 1h, which persisted even after 3d. This study represents the first assessment of the effects of FBF and SFX exposure on symbiotic bacteria in B. communis, expanding our understanding of how insecticides influence natural enemies and their symbiotic bacterial relationships. This study provides theoretical guidance for field applications of FBF and SFX, as well as a reasonable basis for exploring chemical resistance conferred by symbiotic bacteria.

Our study aimed to establish the association of polymorphic variants and disease susceptibility in arsenic-induced metabolic disorders raised due to the variability of arsenic methylation in human population exposed to arsenic in drinking water. Water samples were systematically collected from various regions of Faisalabad, Pakistan, and subjected to arsenic quantification through inductively coupled plasma emission spectrophotometry (ICP-OES). The groundwater exhibited significantly elevated arsenic concentrations (68.18 ± 21.28 μg/L) in comparison to both water and sanitation agency Faisalabad (WASA)-supplied water (9.81 ± 1.2 μg/L) and locally filtered water (8.12 ± 1.42 μg/L), as determined by one-way ANOVA followed by Bonferroni's post-test at P < 0.05. An association was established between arsenic concentration and the incidence of disease, such as diabetes mellitus. A cohort of 120 participants residing in six areas of District Faisalabad was recruited. Urine and blood specimens were collected for analysis. Urine samples underwent ICP-MS analysis in helium collision mode, utilizing germanium as an internal standard. Blood samples were collected for biomarker assessments, including HbA1c, BUN, creatinine, CRP, ALT, AST, GSH, SOD, and MDA, to investigate the evidence of diabetes mellitus. Urinary arsenic concentrations were found to be considerably higher (P < 0.05) in about 22.50 % of the participants, with a mean value of 68.43 ± 16.73 ppb. Biomarker analysis in these participants revealed mean values for BUN (37.19 ± 2.87 mg/dL), creatinine (2.58 ± 0.18 mg/dL), IL-6 (11.35 ± 6.98 pg/mL), CRP (1.90 ± 0.26 mg/dL), MDA (3.70 ± 0.18 nmol/mL), ALT (40.27 ± 5.41 U/L), and AST (38.92 ± 4.72 U/L). Furthermore, the gender-based analysis indicated the higher levels of DMA, MMA, TAs, and TiAs in males compared to females when urine samples were analyzed with HPLC-ICP-MS. Participants with the positive genotype of GSTM exhibited significantly higher levels of TAs, and TiAs concentration in their urine than those with the null genotype of GSTM. Moreover, participants with positive genotypes for GSTT1 and GSTM1 demonstrated elevated levels of DMA in their urine compared to those with genotypes of GSTT1 (−) and GSTM1 (−), although this difference did not attain statistical significance. Participants with the genotype of GSTT1 (+) displayed a considerably higher secondary methylation index than those with genotype of GSTT1 (−). MMA and DMA levels were found to be correlated with the genotypes of GSTT1 and GSTM1 and the amounts of TAs in urine. In conclusion, our findings suggest a linkage between arsenic methylation, particularly levels of DMA and SMI, and GSTT1 and GSTM1 polymorphisms.

Microplastic (MP) contamination in freshwater systems is a prevalent and persistent environmental issue, yet their occurrence and distribution remain poorly constrained. The present study examines the MPs abundance in sediment and water samples and factors controlling their distribution in the Manasbal Lake, north-western (NW) Himalaya. Additionally, the study investigates the relationship between heavy metals and the distribution of MPs in sediment, as well as their potential interactions. The MPs counts in lake surface sediment and water samples varied from 840 nkg⁻¹ to 4020 nkg⁻¹ and 13 nL⁻¹ to 89 nL⁻¹, respectively. The MPs distribution in Manasbal Lake exhibited spatial heterogeneity, with the greatest abundance observed in the eastern and northeastern areas near lake inlets. Grain size and land use appear to collectively modulate the variability of MPs in Manasbal Lake sediments. Five main MPs types were identified: beads/pellets, fragments, fibres, foams, and films, with beads being the predominant type. Polypropylene, polyethylene, and polystyrene are the dominant constituents of the observed MPs, with domestic sewage suggested as the predominant source for their abundance in the lake. Furthermore, the contamination factor for heavy metals indicated a high level of lead contamination in surface sediments, while copper and cobalt showed moderate contamination near the lake inlet. The SEM-EDS analysis illustrated the presence of toxic elements such as Hg, Zn, Pb, Cr, Cd, Ni, and Cu to the surface of MPs. This study expands the baseline characterization of MPs in freshwater systems and enhances our understanding of the potential sources and factors influencing MP distribution.

The Yellow River is the main source of water for urban and rural area and agricultural irrigation in northern China. Herein, the distribution and risk assessment of perfluoroalkyl acids (PFAAs) were investigated from the Yellow River in Shandong Province, China. The total concentration of PFAAs (∑PFAAs) in surface water and sediments were 37.5–2128 ng/L (mean: 167 ng/L) and not detected−6.95 ng/g dry weight (dw) (mean: 1.02 ng/g dw), respectively. Short-chain PFAAs-perfluorobutanoic acid (PFBA), perfluorohexanoic acid (PFHxA), and perfluorobutane sulfonic acid (PFBS) were the most prevalent PFAAs in surface water. Source analysis showed that firefighting foam (proportion: 31.3 %) and textile treatments and food packaging (proportion: 30.3 %) were the main sources of PFAAs in water. Based on the concentration of PFAAs in water, ecological and potential human health risks were assessed. Perfluorooctanoic acid (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA) and perfluoroundecanoic acid (PFUnDA) posed nonnegligible ecological risk for some aquatic organisms. Levels of PFAAs (e.g., PFOA, PFNA, and PFDA etc.) in some water samples were higher than the advisory guidelines of PFAAs concentrations in water worldwide, indicating a potential human health risk. Therefore, PFOA, PFNA, PFDA, and PFUnDA are the key focus of pollutants in the water of the Yellow River in Shandong Province, and the standards and limits of these PFAAs in environments including surface water and sediment should be promoted.

Antibiotics were discovered for medicinal applications, notably in the last century and since then, they have been prevalently employed for prophylactic purposes in various sectors in the last few decades. Due to the non-judicial usage of antibiotics in sectors like agriculture, aquaculture, and animal husbandry, and as therapeutic substances, antibiotics have started to become a nuisance for the environment and human beings. Furthermore, the accumulation of antibiotics in the biosphere has led to the development of antibiotic resistance in microorganisms making it difficult to treat a growing number of infections. Hereafter to understand the holistic picture of the impacts associated with antibiotics on the environment, the evolution of individual antibiotic pathways for therapeutic and non-therapeutic purposes needs to be studied along with their effect on the environment. Most of the recent reviews on antibiotics either concentrate on a particular source, pathway or environmental impact; however, the present state-of-the-art review attempts to summarize and update the possible sources of antibiotics, usage, their impact on humans, and environmental health on a global scale with a special emphasis on India. Also, there is a critical discussion about the various methods employed for the removal of antibiotics from an array of sources, on both water and soil matrix. The review finally emphasize that the implication of stringent regulation and selection of appropriate technology are required to alleviate antibiotics menace from the environment.

The incidence of mycotoxin occurrence throughout the entire lifespan of some agricultural products could be due to climatic conditions and environmental factors (including high temperature, drought, and heavy rainfall) that enhance growth of fungi. Deoxynivalenol (DON) which is also referred to as vomitoxin is a mycotoxin produced from many Fusarium species. DON ranks high among the prominent mycotoxins in cereal products and is a ubiquitous toxin in livestock feeds. DON's adverse effects present major health challenges in both livestock and humans. The use of natural sorbents including smectite clays, is an economically feasible strategy to mitigate mycotoxin toxicities. Previous studies have demonstrated the potential of edible clays as protective components of human food and animal feed to alleviate toxicity associated with short-term exposure to mycotoxins including DON. Hence, this study was designed to investigate the sorption mechanisms of DON onto the binding surfaces of beidellite clay, assessing essential binding parameters such as enthalpy, free energy, binding capacity, affinity, and plateau surface density. These markers were used to predict availability of DON under the experimental conditions. Furthermore, the protection of beidellite clay against DON-induced toxicity was carried out using living organisms susceptible to DON toxicity, including Hydra vulgaris and Lemna minor. These studies investigated the dose-dependent detoxification of DON by 0.05–2 % inclusion of beidellite. Beidellite exhibited more than 75 % protection in Lemna minor and 53 % in Hydra vulgaris validating that this clay is effective in detoxifying DON. During emergencies, or after disasters, inclusion of edible clay like beidellite in food, water or capsules could reduce bioavailability of DON and halt potential exposures to humans and animals.