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Ammonia removal by nitrifiers at the extremely high salinity poses a great challenge for saline wastewater treatment. Sequencing batch reactor (SBR) was conducted with a stepwise increase of salinity from 10 to 40 g-NaCl·L−1, while sequencing batch biofilm reactor (SBBR) with one-step salinity enhancement, their nitrification performance, microbial structure and interaction were evaluated. Both SBR and SBBR can achieve high-efficiency nitrification (98% ammonia removal) at 40 g-NaCl·L−1. However, SBBR showed more stable nitrification performance than SBR at 40 g-NaCl·L−1 after a shorter adaptation period of 4–15 d compared to previous studies. High-throughput sequencing and metagenomic analysis demonstrated that the abundance and capability of conventional ammonia-oxidizing bacteria (Nitrosomonas) were suppressed in SBBR relative to SBR. Gelidibacter , Anaerolineales were the predominant genus in SBBR, which were not found in SBR. NorB and nosZ responsible for reducing NO to N 2 O and reducing N 2 O to N 2 respectively had s strong synergistic effect in SBBR. This study will provide a valuable reference for the startup of nitrification process within a short period of time under the extremely high NaCl salinity. [Display omitted] • High efficiency nitrification was achieved in SBR and SBBR at the salinity of 40 g-NaCl L−1. • SBBR showed more stable nitrification performance than SBR after adapting to 4% NaCl salinity within 20 days. • No nitrite accumulation was found at the stable nitrification period under varying salinity. • More abundant microbial diversity prevailed in SBBR, especially anaerobic bacteria replacing nitrifiers as the dominant genus. • Synergistic interactions between norB and nosZ were induced by microaerobic zones in SBBR. [ABSTRACT FROM AUTHOR]

Bis(2-ethylhexyl) phthalate (DEHP) has been widely concerned owing to its widespread detection and endocrine disrupting effect. Nevertheless, systematic analysis and evaluation of the current status of DEHP contamination are still insufficient for children and adolescents. Dietary exposure and nondietary exposure to DEHP were investigated to estimate the total average daily dose (ADD). The top three contributors were dust exposure, edible oil and vegetable intake. Dietary intake contributed highly (70%) to daily exposure to DEHP. By analyzing the monitoring data on DEHP exposure, the cumulative health risks of DEHP were assessed for different age groups of children and adolescents in East China. The probability distributions of noncarcinogenic and carcinogenic risks were determined by Monte Carlo simulation. The results showed that the risk level reduced with age. The predicted mean noncarcinogenic and carcinogenic risks for all age groups exceeded the acceptable level, indicating that the general population would be at high risk by DEHP overexposure. Schoolchildren at ages 6∼<9 were more susceptible to DEHP exposure, with a 30% possibility of exceeding the safety limit Based on these results, gradual banning and restriction should be carried out to decrease DEHP contamination and potential health risks. • Dietary intake accounted for nearly 70% of daily DEHP exposure. • DEHP exposure could represent a possible health concern for children and adolescents. • The difference of ADD in females and males was insignificant. • 30% of the possibility for schoolchildren exceed the safety limit in East China. [ABSTRACT FROM AUTHOR]

Mercury (Hg) is one of the most toxic pollutants to aquatic organisms. The influence of salinity on Hg toxicity, an important factor restricting the development of global marine aquatic life criteria (ALC), is unclear. Therefore, mercury toxicity data were corrected based on salinity using the aggregate slope method, and the ALC values were derived. Short-term aquatic life criteria (SALC) and long-term aquatic life criteria (LALC) were derived using the species sensitivity distribution method based on Log-logistic, Log-normal, Burr III, Gumbel, and Weibull models. The hazard quotient (HQ) and joint probability curve (JPC) methods were used to evaluate the ecological risk of Hg in the coastal waters of China. The results showed that the SALC and LALC of Hg in the coastal waters of China were 2.21 and 0.54 μg/L. The toxicity data and salinity were positively correlated for Chordate and Arthropoda and negatively correlated for Mollusca. The SALC values increased by approximately 75%, with salinities ranging from 10 to 20 ppt. A slight peak in the SALC at mid-salinities was also observed. The ecological risk assessment of Hg in China's coastal waters showed that attention should be paid to Hg pollution in the Bohai Sea and East China Sea, especially the ecological risk of Hg to crustacean organisms. This study could promote the development of water quality criteria for coastal waters and provide a technical reference for mercury management in the coastal waters of China. • Temporal and spatial distribution of Hg in China's coastal waters were analyzed. • The SALC and LALC were derived based on species sensitivity distribution method. • Salinity correction method was used to study effect of salinity on toxicity and ALC. • HQ and JPC methods were used to assess Hg's ecological risk in China's coastal waters. [ABSTRACT FROM AUTHOR]