Perfluorooctanesulfonic acid (PFOS) is a persistent environmental contaminant previously found in consumer surfactants and industrial fire-fighting foams. PFOS has been widely implicated in metabolic dysfunction across the lifespan, including diabetes and obesity. However, the contributions of the embryonic environment to metabolic disease remain uncharacterized. This study seeks to identify perturbations in embryonic metabolism, pancreas development, and adiposity due to developmental and subchronic PFOS exposures and their persistence into later larval and juvenile periods. Zebrafish embryos were exposed to 16 or 32 μM PFOS developmentally (1–5 days post fertilization; dpf) or subchronically (1–15 dpf). Embryonic fatty acid and macronutrient concentrations and expression of peroxisome proliferator-activated receptor (PPAR) isoforms were quantified in embryos. Pancreatic islet morphometry was assessed at 15 and 30 dpf, and adiposity and fish behavior were assessed at 15 dpf. Concentrations of lauric (C12:0) and myristic (C14:0) saturated fatty acids were increased by PFOS at 4 dpf, and PPAR gene expression was reduced. Incidence of aberrant islet morphologies, principal islet areas, and adiposity were increased in 15 dpf larvae and 30 dpf juvenile fish. Together, these data suggest that the embryonic period is a susceptible window of metabolic programming in response to PFOS exposures, and that these early exposures alone can have persisting effects later in the lifecourse.

Demand for aquatic products surges, due to the increasing concerns on high-quality nutrition and food security. Eastern China is the leading area in contributing significantly to both production and consumption of aquatic products from inland aquaculture, coastal fishing, and distant-water fishing. It is imperative to comprehensively assess the dietary risks of common chemical hazards, such as polycyclic aromatic hydrocarbons (PAHs) in aquatic products of these supply origins, and the contribution of aquatic product consumption to total human exposure. The observed body loads of total PAHs in the coastal aquatic products varied significantly, indicating an unstable food quality from the east coast of China. In the meantime, benzo[a]pyrene equivalent concentrations (BaPₑq) exhibited the highest level in the aquatic products from inland farm ponds. High BaPₑq, along with high consumption of inland aquaculture products, led to higher corresponding cumulative carcinogenic risks (ILCRs) than the other two kinds of products, which further indicate that the origins and consumption rates of the aquatic products do matter. Furthermore, it is confirmed that the consumption of aquatic products is an important contributor to the total daily exposure to PAHs, especially for children and pregnant women. Finally, it is necessary to apply practical remediation in aquaculture farm ponds to provide high-quality products, especially for the population groups of children and pregnant women, and alleviate the exposure and risk due to the PAHs in aquatic products.

Increasing amount of aluminum (Al) gets into aquatic ecosystem through anthropogenic activity, but the knowledge about Al migration and relationships with sediments possessing different physico-chemical properties in eutrophic lakes is limited. Here, the Al migration rule and relationships with sediment nutritions in the Hangzhou West Lake, China was investigated, where a certain amount of residual Al-salts can enter because of the pre-treatment of the Qiantang River diversion project every day. Results revealed the obvious spatial distribution heterogeneity of Al in sediment vertical direction and horizontal direction following water flow. The Al content in sediment ranged 0.463–1.154 g kg⁻¹ in Maojiabu Lake, and ranged 9.862–40.442 g kg⁻¹ in Xiaonanhu Lake. Higher Al content distributed in upper layer sediment in lake with more disturbance. Total nitrogen (TN) contents were higher 0.917–3.387 mg g⁻¹ and 0.627–0.786 mg g⁻¹ in upper layer sediment than that in lower layer in Maojiabu Lake and Xiaonanhu Lake, respectively. Total phosphorus (TP) content ranged 0.779–2.580 mg g⁻¹, in which IP and Fe/Al-P contributed 24.9–80.8% and 17.0–51.6%, respectively. Correlations between Al content with nutrition, humic acid (HA) etc. of sediment regionally varied in Maojiabu and Xiaonanhu Lake. Spatial distribution of Al-salt in eutrophic lakes closely related with the physico-chemical characteristics of nutrients, humus, human disturbance and water division parameters. Results provides new insight into Al-salts migration and references for Al-risk evaluating in eutrophic lakes.

Obesity and exposure to particular matter (PM) have become two leading global threats to public health. However, the exact mechanisms and tissue-specificity of their health effects are largely unknown. Here we investigate whether a metabolic challenge (early nutritional obesity) synergistically interacts with an environmental challenge (PM exposure) to alter genes representing key response pathways, in a tissue-specific manner. Mice subjected to 7 weeks obesogenic nutrition were exposed every other day during the final week and a half to aqueous extracts of PM collected in the city of London (UK). The expression of 61 selected genes representing key response pathways were investigated in lung, liver, white and brown adipose tissues. Principal component analysis (PCA) revealed distinct patterns of expression changes between the 4 tissues, particularly in the lungs and the liver. Surprisingly, the lung responded to the nutrition challenge. The response of these organs to the PM challenge displayed opposite patterns for some key genes, in particular, those related to the Nrf2 pathway. While the contribution to the variance in gene expression changes in mice exposed to the combined challenge were largely similar among the tissues in PCA1, PCA2 exhibited predominant contribution of inflammatory and oxidative stress responses to the variance in the lungs, and a greater contribution of autophagy genes and MAP kinases in adipose tissues. Possible involvement of alterations in DNA methylation was demonstrated by cell-type-specific responses to a methylation inhibitor. Correspondingly, the DNA methyltransferase Dnmt3a2 increased in the lungs but decreased in the liver, demonstrating potential tissue-differential synergism between nutritional and PM exposure. The results suggest that urban PM, containing dissolved metals, interacts with obesogenic nutrition to regulate diverse response pathways including inflammation and oxidative stress, in a tissue-specific manner. Tissue-differential effects on DNA methylation may underlie tissue-specific responses to key stress-response genes such as catalase and Nrf2.

Primitive electronic waste (e-waste) recycling releases large amounts of organic pollutants and heavy metals into the environment. As crucial moderators of geochemical cycling processes and pollutant remediation, soil microbes may be affected by these contaminants. We collected soil samples heavily contaminated by e-waste recycling in China and Pakistan, and analyzed the indigenous microbial communities. The results of this work revealed that the microbial community composition and diversity, at both whole and core community levels, were affected significantly by polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs) and heavy metals (e.g., Cu, Zn, and Pb). The geographical distance showed limited impacts on microbial communities compared with geochemical factors. The constructed ecological network of soil microbial communities illustrated microbial co-occurrence, competition and antagonism across soils, revealing the response of microbes to soil properties and pollutants. Two of the three main modules constructed with core operational taxonomic units (OTUs) were sensitive to nutrition (total organic carbon and total nitrogen) and pollutants. Five key OTUs assigned to Acidobacteria, Proteobacteria, and Nitrospirae in ecological network were identified. This is the first study to report the effects of e-waste pollutants on soil microbial network, providing a deeper understanding of the ecological influence of crude e-waste recycling activities on soil ecological functions.

Microplastic represents a rising proportion of marine litter and is widely distributed throughout a range of marine habitats. Correspondingly, the number of reports of species containing microplastics increases annually. Nephrops norvegicus in the Firth of Clyde have previously been shown to retain large aggregations of microplastic fibres. The potential for N. norvegicus to retain plastic over an extended time period increases the likelihood of any associated negative impacts to the individual. This study represents the longest observation of the impacts of microplastic retention in invertebrates. We exposed N. norvegicus to plastic over eight months to determine the impacts of extended exposure. Over this period we compared the feeding rate, body mass, and nutritional state of plastic-fed N. norvegicus to that of fed and starved control groups. Following the experimental period, the plastic-fed langoustine contained microplastic aggregations comparable to those of small individuals from the Clyde Sea Area. Comparisons between fed, unfed and plastic-fed individuals indicated a reduction in feeding rate, body mass, and metabolic rate as well as catabolism of stored lipids in plastic contaminated animals. We conclude that N. norvegicus exposed to high levels of environmental microplastic pollution may experience reduced nutrient availability. This can result in reduced population stability and may affect the viability of local fisheries.

Numerous pieces of evidence documented the importance of gut microbiota in regulating human health and evaluating the toxicity of environmental pollutants, which are closely related to the host health in various aspects, including nutrition, energy translation, metabolism, pathogen resistance, and immune function. A variety of environmental factors can disrupt gut microbiota and their functions, and inevitably cause immune diseases, obesity and diabetes. However, deciphering the inner mechanisms involved in the functional interaction of gut microbes with host health is still needed extensive investigations. This review focused on the essential roles of intestinal microbes in host-related diseases and highlighted the development and applications of germ-free (GF) animal models, mainly zebrafish. Moreover, the generation, immunity characters, advantages and challenges of GF zebrafish models were also summarized. Importantly, the composition and isolation of zebrafish gut bacteria for further application and toxicity evaluation of aquatic environmental pollutants were also discussed. In conclusion, GF zebrafish play irreplaceable roles in understanding the potential functions and responses of customized microbiota towards human and environmental health implications.

Sulfur, an essential macronutrient, plays important roles in plant development and stress mitigation. Sulfur deficiency, a common problem in agricultural soils, may disturb plant stress resistance and xenobiotic detoxification. In the present study, the function and mechanism of limited sulfur nutrition on the residues and phtotoxicity of imidacloprid were investigated in lettuce plants. Sulfur deficiency significantly increased imidacloprid accumulation in lettuce tissues, exacerbated imidacloprid biological toxicity by enhancing the accumulation of toxic metabolites, like imidacloprid-olefin. Simultaneously, imidacloprid-induced detoxification enzymes including cytochromes P450, glutathione S-transferases (GSTs) and glycosyltransferases were inhibited under limited sulfur supply. On the other hand, sulfur deficiency further enhanced the generation of reactive oxygen species and exacerbated lipid peroxidation in lettuce tissues. Sulfur deficiency mainly reduced the abundance of thiol groups, which are essential redox modulators as well as xenobiotic conjugators, and significantly inhibited GSTs expression. These results clearly suggested that sulfur deficiency inhibited the synthesis of sulfur-containing compounds, leading to increased accumulation of pesticide residues and toxic metabolites as well as reduced detoxification capacity, consequently leading to oxidative damage to plants. Therefore, moderate sulfur supply in regions where neonicotinoid insecticides are intensively and indiscriminately used may be an efficient strategy to reduce pesticide residues and the potential risk to ecosystem.

Methane (CH₄) mitigation of biocovers or biofilters for landfills is influenced by the bed material and oxygen availability. The improvement of active aeration for the CH₄ oxidation efficiency of biochar-amended landfill soil cover was investigated over a period of 101 days. There were column 1 as the control group, column 2 with biochar amending the soil cover, and column 3 with daily active aeration besides the same biochar amendment. All groups were inoculated with enriched methane oxidation bacteria (MOB). The average CH₄ removal efficiency was up to 78.6%, 85.2% and 90.6% for column 1, 2, and 3, respectively. The depth profiles of CH₄ oxidation efficiencies over the whole period also showed that the stimulation of CH₄ oxidation by biochar amendment was apparent in the top 35 cm but became very faint after two months. This probably was due to the rapid depletion of nitrogen nutrition caused by enhanced methanotrophic activities. While through aeration, CH₄ oxidation efficiency was further improved for column 3 than column 2. This enhancement also lasted for the whole period with a reduced decline of CH₄ oxidation. Finally, the major MOB Methylocystis, commonly found in the three columns, were most abundant in the top 35 cm for column 3. A more balanced ratio of MOB and more homogeneous microbial community structures across different soil depths were also the results of active aeration.

Microplastics are a contaminant of emerging concern which enter the marine environment from a variety of sources. The ingestion and toxic effects of microplastics on marine life, especially for filter feeders, are a cause of concern in view of their ubiquitous nature and their similar size as food sources. To assess the toxic effects of microspheres ingested by brine shrimp larvae, we exposed Artemia parthenogenetica to 10 μm polystyrene microspheres at different concentrations. These concentrations were approximate to the extrapolated marine aquatic environmentally relevant concentrations. The lowest polystyrene concentrations at which ingestion was visualized in A. parthenogenetica were 12 ± 0.57 particles/mL (6.7 ± 0.32 μg/L) and 1.1 ± 0.16 particles/mL (0.61 ± 0.088 μg/L), respectively. There were no significant impacts on the survival, growth or development in A. parthenogenetica occurring over the 14-d exposure across a range of polystyrene nominal concentrations (1–1000 particles/mL or 0.55–550 μg/L). However, abnormal ultrastructures of intestinal epithelial cells were observed upon exposure to polystyrene microspheres, including fewer and disordered microvilli, an increased number of mitochondrion and the appearance of autophagosome. These phenomena could affect nutrition absorption and energy metabolism. Although no major acute or chronic toxicity effects on A. parthenogenetica were observed over 24-h or 14-d exposures, this study provides evidence that the ingestion of polystyrene microplastics at extrapolated environmentally relevant concentrations can be visualized through a microscope to be causing a series of responses in intestinal epithelial cells.