Risk associated with increasing bromide in drinking water sources in Yancheng City, China

Pollution characteristics and health risk of sixty-five organics in one drinking water system: PAEs should be prioritized for control

Currently, a large number of emerging organic contaminants have been detected in domestic and international drinking water systems. However, there are differences among the research methods, which lead to system errors in directly comparing the hazards of different contaminants, so it is difficult to analyze the priority control pollutants and the risk control target in drinking water from previous studies. Therefore, we selected a drinking water treatment plant (DWTP) in the east of China, and detected trihalomethanes (THMs), antibiotics, phthalate esters (PAEs), organophosphate esters (OPEs), per and polyfluoroalkyl substances (PFASs), a total of sixty-five organic contaminants in one batch water sample of four seasons, and carried out the whole process monitoring of "Source water-DWTP-Network-Users", and calculated the health risks of contaminants in tap water. The results showed that DWTP could effectively remove antibiotics and PAEs; the removal rate of coagulation for antibiotics can be up to 47%; the release of PAEs in the plastic water supply pipe leads to a significant increase of the concentrations in the water transportation system, which can reach 2.92 times of that in finished water; compared with other contaminants, THMs and PAEs in tap water have higher health risks. This study reveals that THMs and PAEs are priority control organic pollutants, and the water supply network is the key risk control target in the drinking water system, providing a theoretical basis for how to ensure the safety of drinking water.

Bromide-intrusion into Chlorella sp. and Microcystis aeruginosa growing environments: Its impacts on algal growth and the formation potential of algal-derived DBPs upon chlorination

Due to the negative impact of climate change and anthropogenic activities, bromide intrusion into algae-impacted freshwater becomes a new challenge for safe drinking water supply worldwide, as bromide and algal organic matter are important disinfection byproduct (DBP) precursors. However, the influences of this phenomenon on algal precursor dynamic and their derived DBPs have to date received little attention. This study examined the effects of bromide intrusion on algal intra- (IOM) and extra-cellular (EOM) precursors during the growth of two freshwater algae Chlorella sp. and Microcystis aeruginosa. Both algae were well-adapted to Br-intrusion, and no significant effect on their growth and their IOM and EOM precursor characteristics was statistically found (p > 0.05). Notwithstanding, this phenomenon apparently added bromide ions into the algal-EOM solution, which resulted in a linear uptake of bromide by IOM. Under Br-intrusion from 0-4 mg/L (Br0-Br4), 15-60% (on average) of the initial bromide additions remained in the algal EOM. By contrast, only an average of ~1.5-2.4% of the additional bromide was taken up by the IOM, resulting in an elevation of brominated DBPs (Br-DBPs) upon chlorination, especially for those samples collected in the late exponential and declined growth phases. When Br0 shifted to Br4, the %Br-DBP yields from both IOM and EOM increased by more than 75%, with a corresponding increasing the total DBP yield of ~30%. The toxic potencies of all chlorinated Br-containing IOM/EOM were thus magnified, by over one order magnitude greater than the non-Br IOM/EOM at Br0. These results are highly significant for understanding the potential risks of Br-intrusion and algal blooming in raw water quality prior to chlorination.

Progressing towards Environmental Health Targets in China: An Integrative Review of Achievements in Air and Water Pollution under the “Ecological Civilisation and the Beautiful China” Dream

Despite the positive effect of industrialisation on health and quality of life indicators across the globe, it is also responsible for the release of chemical toxins into the environment. Thus, the pursuit of economic development through industrialisation has equally nurtured numerous environmental disasters with accompanying catastrophic health effects. China is one of the countries with high carbon emissions, but new policy changes have resulted in massive gains in controlling environmental damage while enhancing the environment-related quality of life. This paper combines the six-step integrative review strategy with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) strategy to determine appropriate exclusion and inclusion criteria to explore the available stock of literature. We note that overall pollution in China fell by 10% between 2014 and 2019 whereas the average fine particulate matter (PM2.5) concentration of 93 micrograms per cubic meter reduced by 47% by 2019. Beijing exhibited the top 200 most polluted cities in 2019 after recording the lowest PM2.5 ever. All cities that implemented the 2012 Environmental Air Quality Standards reduced the average concentration of PM2.5 and sulfur dioxide by 42–68% by the end of 2018. Improvements in freshwater quality and a decline in water pollution levels were recorded despite increases in economic growth, urbanisation, energy use, trade openness, and agriculture, all of which are major stimulants of pollution. Deterring environmental tariff, tight ecological inspections, closing down of non-compliant producers, heavy investment in environmental control, and the ambitious five year-plan to revitalise renewable energy goals emanating from China’s ecological civilisation masterplan are responsible for these improvements in air and water pollution. China needs to work more aggressively to consolidate the gains already made in order to quicken the actualisation of the ecological civilisation and beautiful China dream.