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141.
Today, many raw materials used in factories may have a dangerous effect on the physiological system of workers. One of them which is widely used in the polyurethane factories is diisocyanates. These compounds are widely used in surface coatings, polyurethane foams, adhesives, resins, elastomers, binders, and sealants. Exposure to diisocyanates causes irritation to the skin, mucous membranes, eyes, and respiratory tract. Hexamethylene diamine (HDA) is metabolite of hexamethylene diisocyanate (HDI). It is an excretory material by worker’s urine who is exposed to HDI. Around 100 air samples were collected from five defined factories by midget impinger which contained dimethyl sulfoxide absorbent as a solvent and tryptamine as reagent. Samples were analyzed by high-performance liquid chromatography with EC\UV detector using NIOSH 5522 method of sampling. Also, 50 urine samples collected from workers were also analyzed using William’s biological analysis method. The concentration of HDI into all air samples were more than 88 xxxμg/m3, and they have shown high concentration of pollutant in the workplaces in comparison with NIOSH standard, and all of the workers’ urine were contaminated by HDA. The correlation and regression test were used to obtain statistical model for HDI and HDA, which is useful for the prediction of diisocyanates pollution situation in the polyurethane factories.  相似文献   
142.
143.
This study was carried out to determine the sorption-desorption, degradation and leaching of napropamide in selected Malaysian soils. The sorption capacities of the selected Malaysian soils for napropamide were the following in descending order: Linau > Teringkap > Gunung Berinchang > Jambu > Rudua > Baging soil. The results indicate that napropamide degradation decreased with increasing soil sorption capacity. Napropamide was leached out earlier in the Baging soil than the other soils. Overall, the application of napropamide in the selected Malaysian soils would not pose a threat to the environment except in soil with low organic matter and clay content and high hydraulic conductivity, such as the Baging soil.  相似文献   
144.
The present study investigates the physical, chemical, and biological characteristics of spring water samples in Shoubak area in the southern Jordan. The samples were collected from May 2004 to May 2005. All samples were analyzed for temperature, conductivity, dissolved oxygen, pH, major cations (Ca2+, Mg2+, K+, Na+), major anions (Cl, NO3, HCO3, SO42−, PO43−, F), and trace metals (Fe2+, Al3+, Mn2+, Cu2+, Cr3+, Ni2+, Zn2+, Pb2+, Cd2+). Water quality for available springs showed high salinity through long period of contact with rocks. The ion concentrations in the water samples were from dissolution of carbonate rocks and ion exchange processes in clay. The general chemistry of water samples was typically of alkaline earth waters with prevailing bicarbonate chloride. Some springs showed elevated nitrate and sulfate contents which could reflect to percolation from septic tanks, cesspools, and agricultural practices. The infiltration of wastewater from cesspools and septic tanks into groundwater is considered the major source of water pollution. The results showed that there were great variations among the analyzed samples with respect to their physical, chemical and biological parameters, which lie below the maximum permissible levels of the Jordanian and WHO drinking water standards. The results indicate that the trace metals of spring’s water of Shoubak area do not generally pose any health or environmental problems. Factor analysis was used to identify the contributers to water quality. The first factor represents major contribution from anthropogenic activities, while the second one represents major contribution from natural processes.  相似文献   
145.
In this work, the effect of meteorological parameters and local topography on mass concentrations of fine (PM2.5) and coarse (PM2.5-10) particles and their seasonal behavior was investigated. A total of 236 pairs of samplers were collected using an Anderson Dichotomous sampler between December 2004 and October 2005. The average mass concentrations of PM2.5, PM2.5-10, and particulate matter less than 10 microm in aerodynamic diameter (PM10) were found to be 29.38, 23.85, and 53.23 microg/m3, respectively. The concentrations of PM2.5 and PM10 were found to be higher in heating seasons (December to May) than in summer. The increase of relative humidity, cloudiness, and lower temperature was found to be highly related to the increase of particulate matter (PM) episodic events. During non-rainy days, the episodic events for PM2.5 and PM10 were increased by 30 and 10.7%, respectively. This is a result of the extensive use of fuel during winter for heating purposes and also because of stagnant air masses formed because of low temperature and low wind speed over the study area.  相似文献   
146.
Blubber samples of Indo-Pacific bottlenose (Tursiops aduncus) and spinner (Stenella longirostris) dolphins from Zanzibar, East Africa, were analyzed for a wide range of organohalogen compounds. Methoxylated polybrominated diphenyl ethers (MeO-BDEs), presumably biogenic, were found at higher concentrations than anthropogenic organochlorine pesticides (OCPs). Only traces of industrial pollutants, such as polychlorinated biphenyls, were detected. The OCP levels found off Zanzibar were lower than those reported from other regions while MeO-BDE levels were higher. The relative composition of the OCPs indicated recent use of lindane (γ-hexachlorocyclohexane) and aged residues of DDT and technical HCH. Placental transfer was estimated to 2.5% and 0.5% of the total burden of OCPs and MeO-BDEs, respectively. Overall transfer from mother to calf in Indo-Pacific bottlenose dolphins was estimated to 72% and 85% for the OCPs and MeO-BDEs burdens, respectively. Health effects of MeO-BDEs are not known, but structural similarities with well-known environmental toxins are cause for concern.  相似文献   
147.
Accelerated eutrophication of surface water is often caused by high phosphorus (P) losses from agricultural fields. Long-term measurements of P concentrations from arable fields are therefore important for understanding of processes and key factors behind losses. Unfortunately, long-time series are difficult to compare due to high variablity, non-normal distribution, precipitation variability and flow relatedness. The objective was to use locally weighted scatterplot smoothing (LOWESS) and Seasonal Kendall Test to account for discharge effects on concentrations of P forms and suspended soil material, and to identify trends for seven agricultural fields included in a Swedish water quality monitoring program. Soil P content and sorption capacity governed concentrations and losses of dissolved reactive phosphorus (DRP). Other factors, such as preferential flow may influence the importance of these factors. Suspended soil material and unreactive phosphorus (UP) concentrations in water discharge depended on soil texture, slope of the field and total soil P content. Statistically significant trends in concentrations of different P forms were found for two fields. These trends are probably a consequence of changes in P additions and soils P saturation levels.  相似文献   
148.
Environment, Development and Sustainability - Prayagraj City is one the biggest cities in the State of Uttar Pradesh which has been selected as Smart City by Ministry of Housing and Urban Affairs,...  相似文献   
149.
Firn core methanesulphonic acid (MSA) stratigraphy from Talos Dome (East Antarctica) was compared with anomalies of the satellite-measured sea ice extent (1973–1995) in the Ross Sea and Wilkes Land oceanic sector. In spite of the sparseness of sea ice data, the MSA maxima fit with many positive sea ice anomalies in the Ross Sea. This evidence suggests that marine biogenic activity enhanced by large sea ice cover is an important, but not exclusive, factor in controlling MSA concentration in snow precipitation at Talos Dome. Other than source intensity, differences in regional atmospheric transport mechanisms affect the arrival of MSA-rich aerosol at Talos Dome. To clarify the role of transport processes in bringing biogenic aerosol to Talos Dome, a spectral analysis was applied to the MSA, SOI (South Oscillation Index), and SAM (Southern Annular Mode) record. Synchronicity or phase shift between the chemical signature and atmospheric circulation modes were tested. The variations in the MSA profile have a periodicity of 6.9, 4.9, 3.5, and 2.9 years. The 6.9 and 2.9 year periodicities show a strong positive correlation and are synchronous with corresponding SOI periodicity. This variability could be related to an increase in MSA source intensity (by dimethylsulphide from phytoplanktonic activity) linked to the sea ice extent in the Ross Sea area, but also to an increased strength in transport processes. Both of these factors are correlated with La Niña events (SOI positive values). Furthermore, SAM positive values are related to an increased sea ice extent in the Ross Sea sector and show two main periodicities 3.3 and 3.8 years. These periodicities determine the MSA variability at 3.5 years. However, the effect of intensification of the polar vortex and the consequent reduction in transport process intensity, which reduce the delivery of air masses enriched in MSA from oceanic areas to Talos Dome, make the effect of the SAM on the MSA concentration at Talos Dome less active than the SOI. In this way, snow deposition at the Talos Dome records larger MSA concentration by the combined effects of increased source emissions and more efficient transport processes. The MSA record from Talos Dome can therefore be considered a reliable proxy of sea ice extent when the effect of changes in transport processes in this region of Antarctica is considered. Over the previous 140 years, these conditions occur with a periodicity of 6.9 years.  相似文献   
150.
On January 29, 2015, the city of Tampere environmental health officers were informed of a possible foodborne outbreak among customers who had eaten lunch in restaurant X. Employees of electric companies A and B had a sudden onset of gastrointestinal symptoms. We conducted a retrospective cohort study to identify the vehicle, source, and causative agent of the outbreak. A case was defined as an employee of companies A or B with diarrhea and/or vomiting who ate lunch at Restaurant X on January 26, 2015. All employees of the companies attending the implicated lunch were invited to participate in the cohort study. Environmental investigation was conducted. Twenty-one responders were included in statistical analysis, of which 11 met with the case definition. Of the 15 food items consumed by participants, four food items were associated with gastroenteritis. Of four kitchen staff, three tested positive for norovirus GIP7, the strain was found earlier in the community. No patient samples were obtained. Level of hygiene in the kitchen was inadequate. Infected kitchen staff probably transmitted norovirus by inadequate hygiene practices. No new cases associated with Restaurant X were reported after the hygiene practices were improved.  相似文献   
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