Three important groups of semi-volatile organic compounds (SVOCs), polycyclic aromatic hydrocarbons (PAHs), organic chlorinated pesticides (OCPs) and phthalate esters (PAEs), were produced by various human activities and entered the water body. In this study, the pollution profiles of three species including 16 PAHs, 20 OCPs and 15 PAEs in water along the Beijiang River, China were investigated. The concentrations of Σ16PAHs in the dissolved and particulate phases were obtained as 69–1.5 × 102 ng L?1 and 2.3 × 103–8.6 × 104 ng g?1, respectively. The levels of Σ20OCPs were 23–66 ng L?1 (dissolved phase) and 19–1.7 × 103 ng g?1 (particulate phase). Nevertheless, higher levels of PAEs were found both in the dissolved and particulate phases due to abuse use of plastic products. Furthermore, non-cancer and cancer risks caused by these SVOCs through the ingestion absorption and dermal absorption were also assessed. There was no non-cancer risk existed through two kinds of exposure of them at current levels, whereas certain cancer risk existed through dermal absorption of PAHs in the particulate phase in some sampling sites. The results will show scientific insights into the evaluation of the status of combined pollution in river basins, and the determination of strategies for incident control and pollutant remediation. 相似文献
Environmental Science and Pollution Research - Microbial fuel cell (MFC) is a sustainable technology to treat cattle manure slurry (CMS) for converting chemical energy to bioelectricity. In this... 相似文献
Objective: Our study measured the change in head injuries and deaths among motorcycle users in Cu Chi district, a suburban district of Ho Chi Minh City.
Methods: Hospital records for road traffic injuries (RTIs) were collected from the Cu Chi Trauma Centre and motorcycle-related death records were obtained from mortality registries in commune health offices. Head injury severity was categorized using the Abbreviated Injury Score (AIS). Rate ratios (RRs) were used to compare rates pre- and post-law (2005/2006–2009/2010). Cu Chi's population, stratified by year, age, and sex, was used as the denominator.
Results: Of records identifying the transportation mode at the time of injury, motorcyclists accounted for most injuries (3,035, 87%) and deaths (238, 90%). Head injuries accounted for 70% of motorcycle-related hospitalizations. Helmet use was not recorded in any death records and not in 97% of medical records. Males accounted for most injuries (73%) and deaths (88%). The median age was 28 years and 32 years for injuries and deaths, respectively. Compared to the pre-law period, rates of motorcycle injuries (RR = 0.53; 95% confidence interval [CI], 0.49–0.58), head injuries (RR = 0.35; 95% CI, 0.31–0.39), severe head injuries (RR = 0.47; 95% CI, 0.34–0.63), and deaths (RR = 0.69; 95% CI, 0.53–0.89) significantly decreased in the post-law period.
Conclusions: Rates of head injuries and deaths among motorcycle riders decreased significantly after implementation of the mandatory helmet law in Vietnam. To further examine the impact of the motorcycle helmet law, including compliance and helmet quality, further emphasis should be placed on gathering helmet use data from injured motorcyclists. 相似文献
Although Internet cafes have been designated as nonsmoking areas in Korea, smoke-free legislation has allowed the installation of indoor smoking rooms. The purposes of this study were to determine secondhand smoke (SHS) leakage from an Internet café smoking room and to identify factors associated with SHS leakage. PM2.5 (particulate matter with an aerodynamic diameter ≤2.5 μm) mass concentrations were measured simultaneously both inside and outside the door to the smoking room. During each measurement, a field technician observed how long the smoking room door was opened and closed, the direction of door opening, and the number of smokers. A multivariate linear regression model was used to identify the causality of SHS leakage from the smoking room. A time series of PM2.5 concentrations both inside and outside the door to the smoking room showed a similar trend. SHS leakage was significantly increased because of factors associated with the direction of the smoking room door being opened, the duration of how long the smoking room door was opened until it was closed, and the average PM2.5 concentration inside the smoking room when the door was opened. SHS leakage from inside the smoking room to outside the smoking room was evident especially when the smoking room door was opened. Since the smoking room is not effective in preventing SHS exposure, the smoking room should be removed from the facilities to protect citizens from SHS exposure through revision of the current legislation, which permits installation of a smoking room.
Implications: This paper concerns secondhand smoke (SHS) leakage from indoor smoking room. Unlike previous studies, the authors statistically analyzed the causality of PM2.5 concentration leakage from a smoking room using time-series analysis. Since the authors selected the most common smoking room, the outcomes could be generalized. The study demonstrated that SHS leakage from smoking room and SHS leakage were clearly associated with door opening. The finding demonstrated ineffectiveness of smoking room to protect citizens and supports removal of indoor smoking room. 相似文献
Environment, Development and Sustainability - Livelihoods of ethnic minority populations living in the mountains of Northern Vietnam are highly vulnerable to climate-induced natural hazards.... 相似文献
A large number of waste mobile phones have already been generated and are being generated. Various countries around the world have all been positively exploring the way of recycling and reuse when facing such a large amount of waste mobile phones. In some countries, processing waste mobile phones has been forming a complete industrial chain, which can not only recycle waste mobile phones to reduce their negative influence on the environment but also turn waste into treasure to acquire economic benefits dramatically. However, the situation of recycling waste mobile phones in China is not going well. Waste mobile phones are not formally covered by existing regulations and policies for the waste electric and electronic equipment in China. In order to explore an appropriate system to recover waste mobile phones, the mobile phone production and the amount of waste mobile phones are introduced in this paper, and status of waste mobile phones recycling is described; then, the disposal technology of electronic waste that would be most likely to be used for processing of electronic waste in industrial applications in the near future is reviewed. Finally, rationalization proposals are put forward based on the current recovery status of waste mobile phones for the purpose of promoting the development of recycling waste mobile phones in developing countries with a special emphasis on China. 相似文献
• Effects of metabolic uncoupler TCS on the performances of GDMBR were evaluated.• Sludge EPS reduced and transformed into dissolved SMP when TCS was added.• Appropriate TCS increased the permeability and reduced cake layer fouling.• High dosage aggravated fouling due to compact cake layer with low bio-activity. The gravity-driven membrane bioreactor (MBR)system is promising for decentralized sewage treatment because of its low energy consumption and maintenance requirements. However, the growing sludge not only increases membrane fouling, but also augments operational complexities (sludge discharge). We added the metabolic uncoupler 3,3′,4′,5-tetrachlorosalicylanilide (TCS) to the system to deal with the mentioned issues. Based on the results, TCS addition effectively decreased sludge ATP and sludge yield (reduced by 50%). Extracellular polymeric substances (EPS; proteins and polysaccharides) decreased with the addition of TCS and were transformed into dissolved soluble microbial products (SMPs) in the bulk solution, leading to the break of sludge flocs into small fragments. Permeability was increased by more than two times, reaching 60–70 L/m2/h bar when 10–30 mg/L TCS were added, because of the reduced suspended sludge and the formation of a thin cake layer with low EPS levels. Resistance analyses confirmed that appropriate dosages of TCS primarily decreased the cake layer and hydraulically reversible resistances. Permeability decreased at high dosage (50 mg/L) due to the release of excess sludge fragments and SMP into the supernatant, with a thin but more compact fouling layer with low bioactivity developing on the membrane surface, causing higher cake layer and pore blocking resistances. Our study provides a fundamental understanding of how a metabolic uncoupler affects the sludge and bio-fouling layers at different dosages, with practical relevance for in situ sludge reduction and membrane fouling alleviation in MBR systems. 相似文献
Environmental Science and Pollution Research - Heavy metal input from the coastal urbanization and industrialization and their potential ecological risks have been a great concern in the northern... 相似文献
High mountains may play significant roles in the global transport of persistent organic pollutants (POPs). This work aims to investigate the levels, patterns and distribution of semi-volatile organoclorine pollutants and to improve the understanding of the long-range atmospheric transport and fate of contaminants on the Tibetan Plateau. A total of 60 fish samples were collected from eight lakes located between 2813 and 4718 m above sea level across the Plateau. Concentrations of polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) including dichlorodiphenyltrichloroethane and its metabolites (DDTs), hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB) were measured in fish muscle. The results showed that concentrations of DDT, HCH and HCB were comparable to or lower than those found in remote mountains of Europe, Canada and US, while PCB concentrations in fish were, on average, about 4-150 times lower on Tibet than at other mountain areas. The transport and fate of contaminants in the Plateau are significantly influenced by the unique climatological and meteorological conditions, particularly by the summer Indian monsoon and winter westerly jet stream. 相似文献