Bis(2-ethylhexyl) phthalate (DEHP) is the most common plasticizer. Previous studies have shown DEHP treatment accelerates neurological degeneration, suggesting that DEHP may impact retinal sensitivity to light, neurotransmission, and copulation behaviors. Although its neurotoxicity and antifertility properties have been studied, whether DEHP exposure disrupts vision and how DEHP influences neuromuscular junction (NMJ) have not been reported yet. Moreover, the impact of DEHP on insect courtship behavior is still elusive. Fruit flies (Drosophila melanogaster) were treated with series concentrations of DEHP and observed for lifespan, motor function, electroretinogram (ERG), electrophysiology of neuromuscular junction (NMJ), courtship behaviors, and relevant gene expression. Our results confirmed the DEHP toxicity on lifespan and capacity of motor function and updated its effect on copulation behaviors. Additionally, we report for the first time that DEHP exposure may harm vision by affecting the synaptic signaling between the photoreceptor and the laminar neurons. Further, DEHP treatment altered both spontaneous and evoked neurotransmission properties. Noteworthy, the effect of DEHP exposure on the copulation behavior is sex-dependent, and we proposed potential mechanisms for future investigation.

Multi-stage constructed wetlands (CWs) have been proved to be a cost-effective alternative in the treatment of various wastewaters for improving the treatment performance as compared with the conventional single-stage CWs. However, few long-term full-scale multi-stage CWs have been performed and evaluated for polishing effluents from domestic wastewater treatment plants (WWTP). This study investigated the seasonal and spatial dynamics of carbon and the effects of the key factors (input loading and temperature) in the large-scale seven-stage Wu River CW polishing domestic WWTP effluents in northern China. The results indicated a significant improvement in water quality. Significant seasonal and spatial variations of organics removal were observed in the Wu River CW with a higher COD removal efficiency of 64–66% in summer and fall. Obvious seasonal and spatial variations of CH₄ and CO₂ emissions were also found with the average CH₄ and CO₂ emission rates of 3.78–35.54 mg m⁻² d⁻¹ and 610.78–8992.71 mg m⁻² d⁻¹, respectively, while the higher CH₄ and CO₂ emission flux was obtained in spring and summer. Seasonal air temperatures and inflow COD loading rates significantly affected organics removal and CH₄ emission, but they appeared to have a weak influence on CO₂ emission. Overall, this study suggested that large-scale Wu River CW might be a potential source of GHG, but considering the sustainability of the multi-stage CW, the inflow COD loading rate of 1.8–2.0 g m⁻² d⁻¹ and temperature of 15–20 °C may be the suitable condition for achieving the higher organics removal efficiency and lower greenhouse gases (GHG) emission in polishing the domestic WWTP effluent. The obtained knowledge of the carbon dynamics in large-scale Wu River CW will be helpful for understanding the carbon cycles, but also can provide useful field experience for the design, operation and management of multi-stage CW treatments.

Microcystin-leucine-arginine (MC-LR), as a most common and deleterious variant among all structural analogues of Microcystins (MCs), can cause male reproductive dysfunction. However, its toxic effects on prostate in adult mice have not been invested in detail. In this study, we observed that MC-LR could enter prostate tissues and induce focal hyperplasia and prostate inflammation. Moreover, increased levels of prostate specific antigen (PSA) and prostate acid phosphatase (PAP) in serum of mice following chronic exposure to MC-LR were detected. We also examined increased expression of forkhead box protein M1 (FOXM1) and PSA in human prostate epithelial cells (RWPE-1) treated with MC-LR at low levels, and FOXM1 could regulate PSA expression. Furthermore, MC-LR also induced expression of CyclinD1 via FOXM1/Wnt/β-catenin signaling pathways in RWPE-1 cells, promoting proliferation of prostate epithelial cells, resulting in prostatic hyperplasia in vivo. As a foreign substance, MC-LR also induced immune reaction in RWPE-1 cells mediated by NF-κB pathway, promoting production of pro-inflammatory cytokines and chemokines. Collectively, these findings demonstrated that MC-LR may induce prostatic hyperplasia and prostatitis in mice following chronic low-dose exposure to MC-LR. This work may provide new perspectives in developing new diagnosis and treatment strategies for MC-LR-induced prostatic toxicity.

As a pristine continent, Antarctica provides a good opportunity to study the spatial transport and temporal accumulation of environmental contaminants and the impacts of anthropogenic activities, both of which have given rise to ongoing public concern. In this research, an approach of coupling aquatic time-integrated passive sampling with chemical analysis and bioassays was used to assess pollution by hydrophobic organic contaminants in Antarctic waters. Passive samplers were deployed in waters of Fildes Peninsula, Antarctica, and their extracts were used for chemical analyses of sixty-six hydrophobic organic contaminants belonging to five groups [organophosphorus flame retardants (PFRs), phthalic acid esters (PAEs), polycyclic aromatic hydrocarbons (PAHs), organochlorine pesticides (OCPs), and polychlorinated biphenyls (PCBs)] and in vitro bioassays for endocrine disruption and genotoxicity. In total, twenty pollutants (six PFRs, one PAE, two PAHs, six OCPs, and five PCBs) were quantified, and six PFRs had concentrations that ranged from ND (not detected) to 44.37 ng L−1 in Antarctic waters. The concentrations detected in the waters were generally low and insufficient to have significant in vitro endocrine disruption potential or genotoxicity. The source and transport pathways of PFRs and PAE in Fildes Peninsula were studied, and multiple local sources (wastewater, air traffic, research stations, and animal feces) for different PFRs were proposed. A spatial and temporal analysis showed slight changes in the exposure of OCPs and PCBs in Antarctic waters. Furthermore, a comparison among a variety of Antarctic water sampling cases revealed that passive sampling can be a tool for aquatic time-integrated investigations in polar regions.

Water diversion has been increasingly applied to improve water quality in many water bodies. However, little is known regarding pollution by organic micropollutants (OMPs) in water diversion projects, especially at the supplier, and this pollution may threaten the quality of transferred water. In the present study, a total of 110 OMPs belonging to seven classes were investigated in water and sediment collected from a supplier of the Yangtze River within four water diversion projects. A total of 69 and 58 target OMPs were detected in water and sediment, respectively, at total concentrations reaching 1041.78 ng/L and 5942.24 ng/g dry weight (dw). Polycyclic aromatic hydrocarbons (PAHs) and pharmaceuticals were the predominant pollutants identified. When preliminarily compared with the pollution in the receiving water, the Yangtze River generally exhibited mild OMPs pollution and good water quality parameters, implying a clean water source in the water diversion project. However, in Zongyang and Fenghuangjing, PAHs pollution was more abundant than that in the corresponding receiving water in Chaohu Lake. Ammonia nitrogen pollution in the Wangyu River was comparable to that in Taihu Lake. These findings imply that water diversion may threaten receiving waters in some cases. In addition, the risks of all detected pollutants in both water and sediment were assessed. PAHs in water, especially phenanthrene and high-molecular-weight PAHs, posed high risks to invertebrates, followed by the risks to fish and algae. Pharmaceuticals, such as antibiotics and antidepressants, may also pose risks to algae and fish at a number of locations. To the best of our knowledge, this report is the first to describe OMPs pollution in water diversion projects, and the results provide a new perspective regarding the security of water diversion projects.

Nitrite is a common pollutant in water and is highly toxic to aquatic animals. To reveal the mechanism of salinity in attenuating nitrite toxicity to fish, we measured the physiological responses of juvenile Takifugu obscurus exposed to nitrite concentrations (0, 10, 20, 50, and 100 mg/L) under different salinity levels (0, 10, and 20 ppt) for 96 h. Salinity increased the survival rates of juvenile T. obscurus exposed to nitrite. Changes in key hematological parameters, antioxidant system, malondialdehyde, Na⁺/K⁺–ATPase, and HSP70 indicated that nitrite induced considerable damage to juveniles; salinity mitigated the harmful effects. This finding reflects similar changing trends in both antioxidants and their gene expressions among different tissues. We applied an overall index, an integrated biomarker response (IBR), that increased under high−nitrite condition but recovered to the normal levels under salinity treatment. Analysis of the selected detection indices and IBR values showed that the overall mitigating effect of salinity on nitrite toxicity seems to be at sub-cellular level and associated with complicated physiological responses.

Thiamethoxam is a neonicotinoid insecticide used widely in agriculture to control a broad spectrum of insect pests. To assess potential risks from this compound to non-target aquatic organisms, an outdoor mesocosm study was performed. Mesocosms (1300 L) were treated once with a formulated product with the active substance (a.s.) thiamethoxam at nominal concentrations of 1 (n = 3), 3 (n = 3), 10 (n = 4), 30 (n = 4), and 100 (n = 2) μg a.s./L, plus untreated controls (n = 4). Primary producers (phytoplankton), zooplankton, and macroinvertebrates were monitored for up to 93 days following treatment. Thiamethoxam was observed to have a water column dissipation half-life (DT50) of ≤1.6–5.2 days in the mesocosms. Community-based principal response curve analysis detected no treatment effects for phytoplankton, zooplankton, emergent insects, and macroinvertebrates, indicating a lack of direct and indirect effects. A number of statistically significant differences from controls were detected for individual phytoplankton and zooplankton species abundances, but these were not considered to be treatment-related due to their transient nature and lack of concentration-response. After application of 30 μg a.s./L, slight temporary effects on Asellus aquaticus could not be excluded. At 100 μg a.s./L, there was an effect with no clear recovery of Asellus observed, likely due to their inability to recolonize these isolated test systems. A statistically significant but transient reduction in the emergence of chironomids by day 23 at the 100 μg a.s./L treatment was observed and possibly related to direct toxicity from thiamethoxam on larval stages. Therefore, a conservative study specific No Observed Ecological Adverse Effect Concentration (NOEAEC) is proposed to be 30 μg a.s./L. Overall, based on current concentrations of thiamethoxam detected in North American surface waters (typically <0.4 μg/L), there is low likelihood of direct or indirect effects from a pulsed exposure on primary producers, zooplankton, and macroinvertebrates, including insects, as monitored in this study.

Pollution of agricultural soils by pesticides, such as organochlorine pesticides (OCPs), can be a significant issue since high detection rates of these compounds were reported in our previous studies. However, more uncertain kinds, quantities and density of pollutants remained in soil samples were unidentified. In this study, the total hormonal activities of complex mixtures of both known and unknown contaminants in agricultural soils in mainland China were measured by applying highly sensitive reporter gene assays for detecting agonists/antagonists for estrogen receptor (ER), androgen receptor (AR), progesterone receptor (PR), glucocorticoid receptor (GR) and mineralocorticoid receptor (MR). High detection rates of estrogenic activities and anti-progestogenic activities were observed among the 123 soil samples, reaching 79% and 73%, respectively. More than half of the soil samples showed obvious antagonistic effects against AR and GR. Approximately a third of tested samples exhibited androgenic, progestogenic and glucocorticoidic effects. A total of 72% and 78% soil extracts had mineralocorticoid-like and anti-mineralocorticoid activities, respectively. Significant positive correlations were observed between estrogenic activity and the concentrations of Σdichlorodiphenyltrichloroethanes (DDTs), Σendosulfans, Σchlordanes, heptachlor and Σdrins, respectively, but not other receptors. As a rapid and convenient pre-caution method, determination of endocrine-disrupting potencies of contaminated soils via bioassay could help to identify and define sites that required further attention for ecological risk assessments.

Inflammation may play an important role in the association between exposure to polycyclic aromatic hydrocarbons (PAHs) and atherosclerotic cardiovascular disease (ASCVD) risk. However, the underlying mechanisms remain unclear.To investigate the association of PAHs exposure with ASCVD risk and effects of mean platelet volume (MPV) or Club cell secretory protein (CC16) on the association.A total of 2022 subjects (689 men and 1333 women) were drawn from the baseline Wuhan residents of the Wuhan-Zhuhai Cohort study. Data on demography and the physical examination were obtained from each participant. Urinary monohydroxy PAH metabolites (OH-PAHs) levels were measured by a gas chromatography-mass spectrometry. We estimated the association between each OH-PAHs and the 10-year ASCVD risk or coronary heart disease (CHD) risk using logistic regression models, and further analyze the mediating effect of MPV or plasma CC16 on the association by using structural equation modeling.The results of multiple logistic regression models showed that some OH-PAHs were positively associated with ASCVD risk but not CHD risk, including 2-hydroxyfluoren (β = 1.761; 95% CI: 1.194–2.597), 9-hydroxyfluoren (β = 1.470; 95% CI: 1.139–1.898), 1-hydroxyphenanthrene (β = 1.480; 95% CI: 1.008–2.175) and ΣOH-PAHs levels (β = 1.699; 95% CI: 1.151–2.507). The analysis of structural equation modeling shows that increased MPV and increased plasma CC16 levels contributed 13.6% and 15.1%, respectively, to the association between PAHs exposure and the 10-year ASCVD risk (p < 0.05).Exposure to PAHs may increase the risk of atherosclerosis, which was partially mediated by MPV or CC16.

Environment pollution often occurs as an obvious combined effect involving two (or more) elements, and this effect changes with the concentrations of the different elements. The effects on barley root elongation were studied in hydroponic systems to investigate the toxicity of Cu–Ni combined at low doses and at a fixed concentration ratio. For low doses of Cu–Ni, the addition of Ni (<0.5 μM) to Cu significantly decreased Cu toxicity for barley, but the addition of Cu (<0.25 μM) had no significant effect on Ni toxicity. At a fixed concentration ratio, according to the single effective concentration (EC) (barley root elongation inhibitory concentration) values of Cu and Ni, five sets of Cu–Ni fixed ratios were used: ECn(Cu)+ECm(Ni) (n + m = 100) (ECn and ECₘ indicate toxicity unit value for n% and m% inhibition of barley root length, respectively). The calculated toxicity unit value for 50% inhibition of root length ranged from 0.44 to 0.98 (i.e., <1), indicating a synergistic effect. To consider the interactions between the metal ions, the extended concentration addition model (e-CA) was established by integrating the Cu–Ni interaction into the concentration addition model (CA), and the data of two groups (the low doses of Cu–Ni and at a fixed concentration ratio) were respectively fitted. The e-CA accurately predicted the root length of barley under the Cu–Ni combined action. The correlation coefficient (r) and the root-mean-square error (RMSE) between predicted and observed values were 0.97 and 6.6 (low-dose group) and 0.96 and 8.12 (fixed-ratio group), respectively, and e-CA significantly improved the prediction accuracy compared to the traditional CA model without consideration of the Cu–Ni competition (r = 0.89, RMSE = 14.16). The results provided a theoretical basis for evaluation and remediation of soil contaminated with heavy metal composites.