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[en] Contemporary air pollution control is a very complex problem. It is necessary to identify the sources of various contaminants and their wastes, to select appropriate analytical methods to quantify the concentration of individual elements with adequate accuracy, to assess the impact of certain types of pollution on the environment and human health. Bio monitoring is the most important method for identifying atmospheric pollutants. Bio indicators are used for these investigations. The best bio indicators are considered to be the best bio indicators in air pollution bio monitoring. For this purpose, specimens were collected for the determination of heavy metals and radionuclides in atmospheric air in the western region of Azerbaijan.
[en] Methods to deal with the unwanted by-product of acid-gas combustion in the Claus reaction furnace were presented. The by-product, carbon disulfide (CS2), is disturbing because if it is not converted to H2S in the first catalytic converter, it will appear as a sulfur emission in the tail gas of plants not using reductive clean-up technology. To address this issue, Claus catalysts have been designed specifically for CS2 hydrolysis. Studies have been conducted to determine what type of hydrocarbons lead to CS2 formation. It was concluded that all hydrocarbons result in CS2 production, but that benzene is particularly difficult. Data for a wide range of acid gas compositions and contaminant hydrocarbons at different process conditions was presented. Methods to destroy CS2 in the furnace were also identified
[en] To determine the association between daily air pollution and the hospital admissions for respiratory diseases in children aged from 0 to 17 years in Jinan, China. Generalized linear models were used to explore the acute effects of ambient fine particulate matter (PM2.5) on the children’s hospital admissions for respiratory diseases. We evaluated the lag associations (including lag 0 to lag 3, lag 01, and lag 03) between daily PM2.5 and the number of children’s hospital admissions for respiratory diseases, and stratified by gender, age group (baby group: age 0–1 years; child group: age 1–5 years; student group: age 6–17 years), and cause-specific disease (including upper infection, pneumonia, and acute bronchitis) during 2011–2015. PM2.5 had significant positive impacts on the number of children’s hospital admissions for respiratory disease. The results showed that per 10 μg/m3 increase of PM2.5 at lag 1 was associated with an increase in total and male hospital admissions of 0.23% (95% CI, 0.02%–0.45%) and 0.32% (95% CI, 0.04%–0.06%). The corresponding risk of the student group (age 6–17 years) hospital admissions was increased 0.90% (95% CI, 0.39%–1.42%) at lag 1 day. The corresponding risk of the upper infection was increased 0.96% (95% CI, 0.37–1.55%) at lag 1 day. Males and student groups (age 6–17 years) were more vulnerable to PM2.5 exposure. Upper infection admission was identified as the sensitive disease for children. It is a better way to reduce children’s outdoor activities to avoid health effects when the air pollution increases.
[en] The launch of China's new national urbanization plan, coupled with increasing concerns about air pollution, calls for better understandings of the nexus between urbanization and the air pollution–related health. Based on refined estimates of PM2.5 related mortality in China, we developed an Urbanization–Excess Deaths Elasticity (U–EDE) indicator to measure the marginal PM2.5 related mortality caused by urbanization. We then applied statistical models to estimate U–EDE and examined the modification effects of income on U–EDE. Urbanization in China between 2004 and 2012 led to increased PM2.5 related mortality. A 1% increase in urbanization was associated with a 0.32%, 0.14%, and 0.50% increase in PM2.5 related mortality of lung cancer, stroke, and ischemic heart disease. U–EDEs were modified by income with an inverted U curve, i.e., lower marginal impacts at the lowest and highest income levels. In addition, we projected the future U–EDE trend of China as a whole and found that China had experienced the peak of U–EDE and entered the second half of the inverted U–shaped curve. In the near future, national average U–EDE in China will decline along with the improvement of income level if no dramatic changes happen. However, the decreased U–EDE only implies that marginal PM2.5–related mortality brought by urbanization would decrease in China. Total health damage of urbanization will keep going up in the predictable future because the U–EDE is always positive. - Highlights: • Urbanization in China from 2004 to 2012 led to increased PM2.5 related mortality. • Income modified the marginal PM2.5 related mortality brought by urbanization. • Total PM2.5 related mortality of urbanization will keep going up in the future. • National industrial structure upgrade strategy will mitigate the mortality burdens.
[en] In the current study, the toxicity bioassay of three pollutants abamectin (ABM), thiamethoxam (TMX), and acrylamide (ACR) against land snails Theba pisana was measured. Also, the ecotoxicological effects of dietary exposure to sublethal concentration (1/20 LC50) of these pollutants for 2-week exposure and 1-week recovery on some physiological endpoints evaluated as feeding activity, growth response, and carbonic anhydrase activity as a marker in charge of shell formation and seromucoid level as a marker in charge of mucus synthesis of the snails were studied. The results exhibited that the 48-h LC50 values were 0.91, 313.8, and 45.7 μg/g dry food for ABM, TMX, and ACR, respectively. The sublethal concentrations of these pollutants in the diet after 2-week exposure were found to reduce the food consumption and inhibit growth rate of the snails. Also, the data illustrated that carbonic anhydrase activity was significantly decreased. On the other hand, there was a significant increase in the seromucoid level as a marker responsible for mucus synthesis in ABM- and TMX-exposed snails, while ACR showed significantly decreased level when compared to control. After 1-week recovery, the tested endpoints of treated snails were slightly repaired but still less than that of the untreated animals. The overall outcome of this investigation suggests the utility of this animal as a good bioindicator organism for ABM, TMX, and ACR exposure in pollution monitoring studies.
[en] Alberta is Canada's major producer of fossil fuels and has the highest Canadian per-capita emission rates of carbon dioxide and nitrogen oxides, and the second highest per-capita rate of sulfur oxides. Plans were announced to develop a clean air strategy for Alberta in order to encourage public discussion about harmful emissions to the atmosphere from the production and use of energy in Alberta. Objectives of this strategy include the identification of the most important issues that need to be addressed in developing a clean air strategy; to develop practical actions for reducing emissions; and to develop policy and program recommendations to present to the provincial government. Regional sessions were initiated to provide an opportunity for presentation of views from the public, industry, government, schools, and public interest groups. The proceedings of these sessions are summarized, oral and written submissions are analyzed, and general observations about the recommendations are presented. Potential climate change from accumulation of greenhouse gases, acid rain, smog in cities, and ozone depletion were identified as air quality problems, and emissions reduction options in six main categories were identified. Emissions management approaches included encouragement of voluntary actions, establishment of stricter air quality standards, and using economic tools or approaches. The limited participation in the regional sessions suggested that only a small segment of society is seriously concerned about the issues raised. 1 fig., 3 tabs
[en] In California, significant progress has been made to control emissions from industrial sources as well as from motor vehicles. Nonetheless, policy analysts still debate over whether it makes sense to control motor vehicle emissions through legislated reductions in vehicle use, especially when new vehicle emission standards are becoming even more stringent in California. In this paper, the emission reduction benefits of California's new low-emission vehicles and clean fuels program are reviewed. The air quality management plans of three major metropolitan areas in California are examined, to identify emission reductions needed to meet federal and state air quality standards. For each of these three areas, emission reductions expected from transportation control measure implementation are presented. Then, the extent to which the reductions are open-quotes significantclose quotes and relied upon in each of the local attainment efforts is analyzed. The emission reductions expected from the stringent exhaust emission standards of California's new low-emission vehicles and clean fuels program will not be sufficient to meet mandated clean air standards in the study areas. Based upon our review, transportation control measures appear to be necessary components of the air quality management plans in California's major metropolitan areas. The paper concludes that cost-effective transportation control measures (TCMs) will be needed as a complementary strategy to California's stringent tail-pipe standards in moderate to extreme nonattainment areas
[en] Epiphytic bromeliads have been used as biomonitors of air pollution since they have specialized structures in leaves for absorbing humidity and nutrients available in the atmosphere. Leaves of five bromeliad species were collected in the conservation unit Parque Estadual Ilha do Cardoso, Sao Paulo State, Brazil, and analyzed by INAA. Vriesea carinata was the species showing most accumulation, with the highest mass fractions of K, Na, Rb and Zn. Similar results were previously found for the same species collected in the dense ombrophilous forest. Chemical composition of bromeliads provided an indication of the atmosphere status in the conservation unit. (author)