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05 and 46 ± 17 mg d-1, respectively. Then, we modified an existing mass balance model to predict the indoor air levels of D4 and D5 in both male and female dormitories based on the usage of PCPs. There was a good agreement for D4 and D5 concentrations in female dormitories between modeled and measured concentrations with the ratio of predicted to measured values to be 1.5 and 1.2, respectively, which indicated that use of PCPs was the main source of cVMSs in university dormitories. Mercury (Hg) transformations in sediments are key factors in the Hg exposure pathway for wildlife and humans yet are poorly characterized in Arctic lakes. As the Arctic is rapidly warming, it is important to understand how the rates of Hg methylation and demethylation (wich determine Hg bioavailability) change with temperature in lake sediments. Methylation and demethylation potentials were determined for littoral sediments (2.5 m water depth) in two deep and two shallow lakes in the Canadian Arctic using Hg stable isotope tracers at incubation temperatures of 4, 8, or 16 °C for 24 h. Compared to sediments from other regions, Hg methylation and demethylation potentials in these sediments are low. The maximum depth of the lake from which sediment was collected exerted a stronger influence over methylation potential than sediment Hg concentration or organic matter content; the shallowest lake had the highest Hg methylation potential. click here Sediments from the shallowest lake also demonstrated the greatest response to the temperature treatments, with significantly higher methylation potentials in the 8 and 16 °C treatments. Sediments from the deep lakes demonstrated greater demethylation potentials than shallow lakes. The methylmercury to total Hg ratio in sediments supported the measured transformation potentials as the lake with the greatest methylation potential had the highest ratio. This study supports previous works indicating that Hg methylation potential may increase as the Arctic warms, but demethylation potential does not respond to warming to the same degree, indicating that Hg methylation may predominate in warming Arctic sediments. The body burdens of eight trace metals Cd, Pb, Cu, Zn, Cr, Se, Hg, and As, were measured in live mussels (LMs) Mytilus galloprovincialis at 14 coastal sites in Port Phillip Bay, Victoria, Australia in winter and summer between 2017 and 2018. The spatial and temporal variations of body burdens were evaluated. The results revealed significantly higher body burdens of Cd, Pb, Cu, Zn, Cr, and Hg in summer at the sites where the city centre and industries are located. Elevated levels of most trace metals including 3 toxic, non-essential metals (Cd, Pb, and Hg) were detected in LMs from the site of Geelong. The body burdens of Zn, Cr, Se, and As appeared higher at the sites from the Bellarine Peninsula and the mouth of Port Phillip Bay. Besides, the "Artificial Mussels" (AMs) were deployed at the same sites in summer for 28 d and retrieved when the LMs were collected. The accumulations of the eight metals were compared between AMs and LMs summer results. It indicated significant correlations for Pb, Cu, and Cr, lower correlations in Zn and Hg, and irregular correlations for Se and As. The AM results of Cd were below the detection limit of the analytical method. This study demonstrates that AMs are excellent replacement of LMs for the biomonitoring of multiple kinds of trace metals. The present study evaluated the removal capacity of a UASB-HRAP treatment system, combining anaerobic and microalgae-based, aerobic treatment, for eleven organic micropollutants present in raw sewage, including pharmaceuticals, estrogens and xenoestrogens. The UASB reactor and the HRAP were operated at a hydraulic retention time (HRT) of 7 h and 8 days, respectively. Influent and effluent samples from the UASB and HRAP were collected periodically. All the target compounds were detected in raw sewage, with an occurrence ranging from 70 to 100%. Removal rates in the UASB reactor were generally incomplete, ranging from no removal (-25.12% for the hormone EE2-ethinylestradiol) to 84.91% (E2 - estradiol). However, the overall performance of the UASB + HRAP system was highly efficient for the majority of the compounds, with removal rates ranging from 64.8% (ibuprofen) to 95% (estrone). Gemfibrozil and bisphenol A were the only exceptions, with overall removal rates of 39% and 43%, respectively. Hormones were the compounds with the highest removal rates in the system. The abundance and nitrification activity of ammonia oxidizing archaea (AOA) and ammonia oxidizing bacteria (AOB) in bulk water and biofilm in chloraminated and chlorinated water supply systems were investigated. The abundance of AOB varied between cold and warm periods while that was the case for AOA only in biofilm. Lower ammonia concentrations favored the abundance of AOA over AOB. AOA and AOB were found more in distal zones of the distribution system (DS). Higher numbers of AOA and AOB were observed in DS associated with chloramination compared to those associated with chlorination. Significant positive correlations between ammonia-N in bulk water and AOA indicate a possibility of involvement of AOA in nitrification in DS. A separate laboratory-based experiment simulating DS condition was conducted to understand the effects of chlorine and chloramine dosages and temperature on AOA and AOB. AOA were inhibited less than AOB in the presence of lower concentrations of chlorine and chloramine (1.5 and 2.0 mg/L chlorine; 0.05-0.1 and 0.3-0.4 mg/L chloramine) while both of them were not detected at higher dosages (2.5 mg/L chlorine and 1.5-1.6 mg/L chloramine). At a low temperature (10-12 °C), chloramine and chlorine provided similar inhibition trends in which AOB were inhibited more than AOA. At a high temperature (25 °C), chloramine was less inhibitory to AOA and AOB than chlorine. Widespread use of di (2-ethylhexyl) phthalate (DEHP) as a plasticizer has caused considerable soil pollution; however, little is known about indigenous microbial communities involved in its degradation in soil. In this study, metagenomic sequencing combined with metabolite determination was used to explore microorganisms and genes potentially involved in DEHP degradation in aerobic and anaerobic soils. The results showed that under both dryland aerobic and flooded anaerobic conditions, DEHP was initially hydrolyzed into mono (2-ethylhexyl) phthalate which was then hydrolyzed into phthalic acid; benzoic acid was the central intermediate during further metabolism steps. Bacteria were more responsive to DEHP presence than fungi/archaea, and potential degradative genes stimulated by DEHP were predominantly associated with bacteria, reflecting the dominant role of bacteria in DEHP degradation. Members of the Actinomycetales seemed to be the dominant degraders under aerobic conditions, while a number of phyla i.e. Gemmatimonadetes, Proteobacteria, Acidobacteria and Bacteroidetes appeared to be involved under anaerobic conditions.