The Science of the total environment
-
Sci. Total Environ. · Jan 2017
Occurrence of new psychoactive substances in wastewater of major Chinese cities.
New psychoactive substances have become increasingly popular across the globe in recent years, which may cause certain public health issues. In this work, sewage-based epidemiology was applied to examine the use of two synthetic cathinones, mephedrone and methylenedioxypyrovalerone (MDPV), and three piperazines, benzylpiperazine (BZP), trifluoromethylphenylpiperazine (TFMPP), and 1-(3-Chlorophenyl)piperazine (mCPP), across China. Influent wastewater samples were collected from 36 sewage treatment plants (STPs) in 18 major cities that cover all the geographic regions of the country. ⋯ No clear geographic pattern in BZP occurrence in wastewater was identified. Since BZP in wastewater may also come from its legal sources, whether widespread occurrence of BZP means widespread abuse is yet to be confirmed. Apparent removal of MDPV by wastewater treatment was low (<25%), whereas removal of BZP was nearly complete (typically>95%).
-
Sci. Total Environ. · Oct 2016
Spatial variations in the consumption of illicit stimulant drugs across Australia: A nationwide application of wastewater-based epidemiology.
Obtaining representative information on illicit drug use and patterns across a country remains difficult using surveys because of low response rates and response biases. A range of studies have used wastewater-based epidemiology (WBE) as a complementary approach to monitor community-wide illicit drug use. In Australia, no large-scale WBE studies have been conducted to date to reveal illicit drug use profiles in a national context. ⋯ These ratios imply the difficulty of detecting the trafficking of these stimulants in Australia, possibly more so for methamphetamine than cocaine. The obtained spatial pattern of use was compared with that in the most recent national household survey. Together both WBE and survey methods provide a more comprehensive evaluation of drug use that can assist governments in developing policies to reduce drug use and harm in the communities.
-
Sci. Total Environ. · Oct 2016
Importance of doping, dopant distribution, and defects on electronic band structure alteration of metal oxide nanoparticles: Implications for reactive oxygen species.
Metal oxide nanoparticles (MONPs) are considered to have the potency to generate reactive oxygen species (ROS), one of the key mechanisms underlying nanotoxicity. However, the nanotoxicology literature demonstrates a lack of consensus on the dominant toxicity mechanism(s) for a particular MONP. Moreover, recent literature has studied the correlation between band structure of pristine MONPs to their ability to introduce ROS and thus has downplayed the ROS-mediated toxicological relevance of a number of such materials. ⋯ This commentary critically evaluates the existing material science and nanotoxicity literature and identifies the gap in our understanding of the role of important crystal structure features (i.e., dopants and defects) on MONPs' electronic structure alteration as well as their ROS-generation capability. Furthermore, this commentary provides suggestions on characterization techniques to evaluate dopants and defects on the crystal structure and identifies research needs for advanced theoretical predictions of their electronic band structures and ROS-generation abilities. Correlation of electronic band structure and ROS will not only aid in better mechanistic assessment of nanotoxicity but will be impactful in designing and developing ROS-based applications ranging from water disinfection to next-generation antibiotics and even cancer therapeutics.
-
Sci. Total Environ. · Oct 2016
Cocaine, MDMA and methamphetamine residues in wastewater: Consumption trends (2009-2015) in South East Queensland, Australia.
Wastewater analysis, or wastewater-based epidemiology, has become a common tool to monitor trends of illicit drug consumption around the world. In this study, we examined trends in cocaine, 3,4-methylenedioxymethamphetamine (MDMA) and methamphetamine consumption by measuring their residues in wastewater from two wastewater treatment plants in Australia (specifically, an urban and a rural catchment, both in South East Queensland) between 2009 and 2015. With direct injection of the samples, target analytes were identified and quantified using liquid chromatography-mass spectrometry. ⋯ In contrast, there was a five-fold increase in methamphetamine consumption over this period in this catchment. For methamphetamine consumption, the rural area showed a very similar trend as the urban catchment starting at a lower baseline. The observed increase in per capita loads of methamphetamine via wastewater analysis over the past six years in South East Queensland provides objective evidence for increased methamphetamine consumption in the Australian population while the use of other illicit stimulants remained relatively stable.
-
Sci. Total Environ. · Jul 2016
Effects of long term rice straw application on the microbial communities of rapeseed rhizosphere in a paddy-upland rotation system.
The influence of the rice straw application on rhizosphere microbial communities in the long-term rotation system remains unclear. Two experimental sites (Jingzhou and Wuxue) with the same straw fertilization have been cultivated under the rapeseed-rice rotation mode for 7years. Eco-plate data indicated that the microbial metabolic potential at both sites was enhanced in the cores applied with rice straw. ⋯ Variation in soil enzyme activities could be mainly explained by available potassium in Jingzhou, and it was significantly affected by total soil carbon, available nitrogen, available potassium, available phosphorous, total soil nitrogen, moisture content and total phosphorous in Wuxue. The two rapeseed rhizosphere microbial communities are differently affected by the rice-straw application. Rhizosphere with more fungi was passively influenced by the rice-straw, while that with more Gram-negative bacteria was actively in response to the treatment.