1,2-Dichloroethane causes anxiety and cognitive dysfunction in mice by disturbing GABA metabolism and inhibiting the cAMP-PKA-CREB signaling pathway.

1,2-Dichloroethane (1,2-DCE) is a powerfully toxic neurotoxin, which is a common environmental pollutant. Studies have indicated that 1,2-DCE long-term exposure can result in adverse effects. Nevertheless, the precise mechanism remains unknown. In this study, behavioral results revealed that 1,2-DCE long-term exposure could cause anxiety and learning and memory ability impairment in mice. The contents of γ-aminobutyric acid (GABA) and glutamine (Gln) in mice's prefrontal cortex decreased, whereas that of glutamate (Glu) increased. With the increase in dose, the activities of glutamate decarboxylase (GAD) decreased and those of GABA transaminase (GABA-T) increased. The protein and mRNA expressions of GABA transporter-3 (GAT-3), vesicular GABA transporter (VGAT), GABA A receptor α2 (GABAARα2), GABAARγ2, K-Cl cotransporter isoform 2 (KCC2), GABA B receptor 1 (GABABR1), GABABR2, protein kinase A (PKA), cAMP-response element binding protein (CREB), p-CREB, brain-derived neurotrophic factor (BDNF), c-fos, c-Jun and the protein of glutamate dehydrogenase (GDH) and PKA-C were decreased, while the expression levels of GABA transporter-1 (GAT-1) and Na-K-2Cl cotransporter isoform 1 (NKCC1) were increased. However, there was no significant change in the protein content of succinic semialdehyde dehydrogenase (SSADH). The expressions of adenylate cyclase (AC) and cyclic adenosine monophosphate (cAMP) contents were also reduced. In conclusion, the results of this study show that exposure to 1,2-DCE could lead to anxiety and cognitive impairment in mice, which may be related to the disturbance of GABA metabolism and its receptors along with the cAMP-PKA-CREB pathway.

Non-negligible health risks caused by inhalation exposure to aldehydes and ketones during food waste treatments in megacity Shanghai.

Aldehydes and ketones in urban air continue to receive regulatory and scientific attention for their environmental prevalence and potential health hazard. However, current knowledge of the health risks and losses caused by these pollutants in food waste (FW) treatment processes is still limited, especially under long-term exposure. Here, we presented the first comprehensive assessment of chronic exposure to 21 aldehydes and ketones in urban FW-air environments (e.g., storage site, mechanical dewatering, and composting) by coupling substantial measured data (383 samples) with Monte Carlo-based probabilistic health risk and impact assessment models. The results showed that acetaldehyde, acetone, 2-butanone and cyclohexanone were consistently the predominant pollutants, although the significant differences in pollution profiles across treatment sites and seasons (Adonis test, P < 0.001). According to the risk assessment results, the estimated cancer risk (CR; mean range: 1.6 × 10-5-1.12 × 10-4) and non-cancer risk (NCR; mean range: 2.98-22.7) triggered by aldehydes and ketones were both unacceptable in most cases (CR: 37.8%-99.3%; NCR: 54.2%-99.8%), and even reached the limit of concern to CR (1 × 10-4) in some exposure scenarios (6.18%-16.9%). Application of DALYs (disability adjusted life years) as a metric for predicting the damage suggested that exposure of workers to aldehydes and ketones over 20 years of working in FW-air environments could result in 0.02-0.14 DALYs per person. Acetaldehyde was the most harmful constituent of all targeted pollutants, which contributed to the vast majority of health risks (>88%) and losses (>90%). This study highlights aldehydes and ketones in FW treatments may be the critical pollutants to pose inhalation risks.

Phytoremediation for Co-contaminated Soils of Cadmium and Polychlorinated Biphenyls Using the Ornamental Plant Tagetes patula L.

In this study, pot-culture experiments were conducted to investigate the single effect of Cd, PCBs, and the combined effect of Cd-PCBs with Tagetes patula L. The study highlights that the minimum concentration of PCBs (100 µg kg-1) could enable the growth of the plant with an increase in biomass by 27.76% when compared with the control. In all the experiments performed, the Cd concentrations over the surface parts were found to be above 100 mg kg-1. Significant positive correlations were observed between the Cd and PCBs concentrations accumulated in tissues of the soil and plants (p < 0.05). T. patula exhibited high tolerance to Cd and PCBs, and the plant promoted the removal rate of PCBs. The removal rates of PCB18 and PCB28 were up to 42.72 and 42.29%, respectively. The study highlights the potential and suitability of T. patula for phytoremediation of Cd and PCBs in contaminated soils.

[Variation of estrogenic effects during water treatment processes in a drinking water work in South China].

The variation of estrogenic effects during water treatment processes in a drinking water work in South China was investigated. Water samples were collected from the source water and the different treatment processes. Crude extracts were obtained by solid phase extraction (SPE) using HLB columns and three fractionated extracts were obtained by elution using organic reagents with different polarity. Recombinant gene yeast assay was used to evaluate the endocrine disrupters effects of all the samples. The combination of the recombinant gene yeast assay and the sample fractionation technique was effective to evaluate the estrogenic effects for water samples. All the crude samples showed positive results in the yeast assay and the highest effect was occurred in the source water sample, in which the effects were mainly attributed to the none-polar fraction and the estradiol equivalent concentration was 0.25 pmol/L. 83% estrogenic effects were reduced effectively by the treatment processes.