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Gestational anemia is a complication of pregnancy, and a low level of hemoglobin (Hb) has been linked to adverse pregnancy outcomes. Previous studies reported that PFASs were more strongly associated with Hb than red blood cells, indicating that Hb is more susceptible to the effect of PFASs. However, the evidences regarding the effects of per- and polyfluoroalkyl substances (PFASs) on gestational anemia are currently limited. Therefore, it is important to explore the effects of PFASs on anemia in Chinese pregnant women.A total of 821 pregnant women were recruited between June 2015 and April 2019 in the Guangxi Zhuang Birth Cohort. The concentrations of PFASs were assessed in maternal serum before 12 gestational weeks. To determine both individual and combined associations of PFASs exposure with anemia in the three stages of pregnancy, binary logistic regression, Bayesian kernel machine regression (BKMR), and weighted quantile sum (WQS) regression models were employed.In single-pollutant analysis, maternal exposure to perfluorododecanoic acid (PFDoA) and perfluoroheptanoic acid (PFHpA) were associated with anemia in the first trimester, exposure to PFHpA and perfluorobutanesulfonic acid (PFBS) were associated with anemia in the second trimester, and exposure to perfluorodecanoic acid (PFDA) and perfluorononanoic acid (PFNA) were associated with anemia in the third trimester. Notably, perfluoroundecanoic acid (PFUnA) had a nonlinear association with anemia in the third trimester. In multiple-pollutant analysis, a positive association of PFDoA with anemia in the first trimester and a negative association of PFBS with anemia in the second trimester were confirmed by BKMR. Exposure to PFASs mixture was not associated with anemia in all three trimesters. In WQS, there was a significantly negative association between the PFAS mixture and anemia in the second trimester.Maternal exposure to PFASs is associated with gestational anemia in different trimesters.

In today's society, wastewater sludge has become solid waste, and the preparation of wastewater sludge into sludge biochar nanomaterials (SBCs) for resource utilization has become a promising method. SBCs have advantages over other biomasses, including their complex composition, wide range of raw materials, and especially the presence of various transition metals with catalytic properties. Heterogeneous Fenton processes using SBCs as catalyst carriers have shown great potential in the removal of pollutants. In this review, the synthesis methods of SBCs are reviewed and the effects of different synthesis methods on their physicochemical properties are discussed. Furthermore, the successful applications of raw SBCs, metal-modified SBCs, and Fenton sludge-SBCs in organic pollutant degradation, sediment remediation, and sludge dewatering are reviewed. The mechanisms occurring with different metals as active sites are explored, and the review shows that the degradation efficiency and stability of SBCs are very satisfactory. We also provide an outlook on the future development of SBCs. We hope that this review will help readers gain a clearer and deeper understanding of SBCs and promote the development of SBCs.

Nanoparticles like nano-TiO

In industrial wastewaters, rapid shifts of salinity leading to transient shocks caused damages on biological treatments. Aerobic granular sludge is a promising technology that showed its greater resistance to adverse conditions. However, the impact of short-term saline shocks on the performance of aerobic granular sludge process was not studied sufficiently. This study investigated salt-tolerance ability of aerobic granular sludge from aspects of chemical oxygen demand (COD) removal efficiency and sludge concentration under different saline shocks that shock concentration ranged from 0 to 60 gNaCl/L and shock duration was set at 6 h. The results showed that no obvious change of sludge concentration after all saline shocks. Moreover, COD removal efficiencies could revert to 90.7% and 87.5% that was near to the previous level (90.9%) in short-term recovery after 20 g/L and 40 g/L saline shocks. However, stable COD removal efficiency (73.8%) could not recover to the previous level (90.9%) after 60 g/L saline shock. These results suggest aerobic granular sludge has an excellent ability to withstand up to 40 g/L saline shock. The corresponding salt-tolerance reasons could be explained from three aspects. After 40 g/L saline shock, the specific oxygen uptake rate of aerobic granular sludge could recover to ensure biological activity. Aerobic granular sludge with the integrity coefficients of 87.6% maintained compact structure. In addition, aerobic granular sludge with relative small DNA leakage of 177.2% has advantages to diminish damage on cell structure. These results provide further insight into the application of aerobic granular sludge for saline-shock wastewater treatments.

Aerobic granular sludge (AGS) technology has been recognized as a promising alternative to alleviate the osmotic stress of hypersaline wastewater. However, the response of AGS process to composite hypersaline wastewater on removal performance and populations was yet to be understood. In this work, two sequenced batch reactors were operated in parallel in absence (R0) and presence (R1) of high concentration sulfate as proxy for single and mixed salts (30 g salt·L−1) respectively. Results demonstrated that the presence of sulfate in hypersaline wastewater enhanced chemical oxygen demand (COD) and total nitrogen (TN) removals of 95.3% and 65.5% respectively with lower accumulations of nitrite. High-throughput 16 S rRNA gene sequencing technique elucidated that Denitromonas (31.6%) and Xanthomarina (17.0%) were the more dominant genera in AGS response to mixed salts with high sulfate and laid the biological basis for strengthening removal performance. The enrichment of halophilic Luteococcus (23.5%) in the AGS surface indicated the potential role of mixed salts in shaping the physical properties and surface population structure of AGS. Our work could facilitate the potential applications of AGS technology for industrial hypersaline wastewater treatment with complicated compositions.

The anaerobic-anoxic-aerobic (A2O) process is a highly efficient sewage treatment method, which uses complex bacterial communities. However, the effect of copper on this process and the bacterial communities involved remains unknown. In this study, a systematic investigation of the effect of persistent exposure of copper in the A2O wastewater treatment system was performed. An A2O device was designed to examine the effect of copper on the removal efficiency and microbial community compositions of activated sludge that was continuously treated with 10, 20, and 40 mg L−1 copper, respectively. Surprisingly, a decrease in chemical oxygen demand (COD) and ammonia nitrogen (NH4 N) removal efficiency was observed, and the toxicity of high copper concentration was significantly greater at 7d than at 1d. Proteobacteria, Bacteroidetes, Acidobacteria, Chlorobi, and Nitrospirae were the dominant bacterial taxa in the A2O system, and significant changes in microbial community were observed during the exposure period. Most of the dominant bacterial groups were easily susceptible to copper toxicity and diversely changed at different copper concentrations. However, not all the bacterial taxa were inhibited by copper treatment. At high copper concentration, many bacterial species were stimulated and their abundance increased. Cluster analysis and principal coordinate analysis (PCoA) based on operational taxonomic units (OTUs) revealed clear differences in the bacterial communities among the samples. These findings indicated that copper severely affected the performance and key microbial populations in the A2O system as well as disturbed the stability of the bacterial communities in the system, thus decreasing the removal efficiency.

Widespread contamination of agricultural soil with toxic metals such as cadmium (Cd) is a major threat to crop production and human health. Metallochaperones are a unique class of proteins that play pivotal roles in detoxifying metallic ions inside cells. In this study, we investigated the biological function of an uncharacterized metallochaperone termed OsHIPP29 in rice plants and showed that OsHIPP29 resides in the plasma membrane and nucleus and detoxifies excess Cd and Zn. OsHIPP29 was primarily expressed in shoots during the vegetative stage and in leaf sheath and spikelet at the flowering stage. It can be differentially induced by excess Cd, Zn, Cu, Fe and Mn. To identify the function of OsHIPP29 in mediating rice response to Cd stress, we examined a pair of OsHIPP29 mutants, RNAi lines and transgenic rice overexpressing OsHIPP29 (OX) under Cd stress. Both mutant and RNAi lines are sensitive to Cd in growth as reflected in decreased plant height and dry biomass. In contrast, the OX lines showed better growth under Cd exposure. Consistent with the phenotype, the OX lines accumulated less Cd in both root and shoot tissues, whereas OsHIPP29 knockout led to higher accumulation of Cd. These results point out that expression of OsHIPP29 is able to contribute to Cd detoxification by reducing Cd accumulation in rice plants. Our work highlights the significance of OsHIPP29-mediated reduced Cd in rice plants, with important implications for further developing genotypes that will minimize Cd accumulation in rice and environmental risks to human health.