Effect of indoor air pollution from biomass combustion on prevalence of asthma in the elderly.
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In this study I examined the effect of cooking smoke on the reported prevalence of asthma among elderly men and women greater than or equal to 60 years old). The analysis is based on 38,595 elderly persons included in India's second National Family Health Survey conducted in 1998-1999. Effects of exposure to cooking smoke, ascertained by type of fuel used for cooking (biomass fuels, cleaner fuels, or a mix of biomass and cleaner fuels), on the reported prevalence of asthma were estimated using logistic regression. Because the effects of cooking smoke are likely to be confounded with effects of age, tobacco smoking, education, living standard, and other such factors, the analysis was carried out after statistically controlling for such factors. Results indicate that elderly men and women living in households using biomass fuels have a significantly higher prevalence of asthma than do those living in households using cleaner fuels [odds ratio (OR) = 1.59; 95% confidence interval (95% CI), 1.30-1.94], even after controlling for the effects of a number of potentially confounding factors. Active tobacco smoking was also associated with higher asthma prevalence in the elderly, but not environmental tobacco smoke. Availability of a separate kitchen in the house and a higher living standard of the household were associated with lower asthma prevalence. The adjusted effect of cooking smoke on asthma was greater among women (OR = 1.83; 95% CI, 1.32-2.53) than among men (OR = 1.46; 95% CI, 1.14-1.88). The findings have important program and policy implications for countries such as India, where large proportions of the population rely on polluting biomass fuels for cooking and space heating. More epidemiologic research with better measures of smoke exposure and clinical measures of asthma is needed to validate the findings. (+info)
Overview and characteristics of some occupational exposures and health risks on offshore oil and gas installations.
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This review considers the nature, and recognition and control, of health risks in the offshore oil and gas industry from the occupational hygiene point of view. Particular attention is given to the changes in the nature of exposure and control of inhalation risks from substances hazardous to health in the UK sector, but other risks (e.g. dermatitis, noise and vibration) are also considered. The amount of published information on exposure to these hazards in the sector, or indeed on long-term health outcomes of working offshore, is limited. The approach taken to occupational health and hygiene in the sector has to be set in the context of the challenge of working in a remote and hostile environment where attention to safety and the need for emergency response to acute, rather than chronic, medical events are vital. However, changes in attitudes towards occupational health in the sector, legislation, the impact of environmental protection requirements and technology have all contributed to increasing the attention given to assessment and control of chemical and physical hazards. The health risks and benefits associated with the abandonment of installations, the application of new technologies, recovery of oil from ever deeper waters, lower staffing levels, environmental changes, the ageing workforce and the recognition of exposure patterns needing further attention/control (sequential multiple exposures, smaller workforce, peak/short-term exposures, etc.) are other current and future occupational hygiene challenges. (+info)
Oil degradation in soil.
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The environmental effects of adding certain selected petroleum products to field soils at widely separated geographical locations under optimum conditions for biodegradation were studied. The locations selected for study of soil biodegradation of six oils (used crankcase oil from cars, used crankcase oil from trucks, an Arabian Heavy crude oil, a Coastal Mix crude oil, a home heating oil no. 2, and a residual fuel oil no. 6) were Marcus Hook, Pennsylvania, Tulsa, Oklahoma, and Corpus Christi, Texas. The investigative process, covering a period of 1 year at each location, was conducted in 14 fields plots (1.7 by 3.0 m) to which the oils were added in a single application at a rate of 11.9 m3/4 X 10(3) m2. One-half of the plots at each location were fertilized, and the incorporation of the oils and fertilizers was accomplished with rototillers to a depth of 10 to 15 cm. Concentrations of all oils decreased significantly at all locations. The average reduction ranged from 48.5 to 90.0% depending upon the type of oil and location. Rates of degradation did not exceed 2.4 m3/4 X 10(3) m2 per month. Compositional changes in the oil with time were investigated using silica gel fractionation, gas chromatography, and ultraviolet absorbance. With the possible exception of the two fuel oils, the compositional changes were generally in the same direction for all of the oils. The silica gel fractionation and gravimetric data on residual oils show that all classes of compounds were degraded, but the more polar type degrade more slowly. Analysis of runoff water, leachate, and soils indicated that at the concentration applied no oil less was observed from these plots via water movement. No significant movement of lead compounds added to the soils in the used crankcase oils was observed. Significant increases in hydrocarbon-utilizing microorganisms were demonstrated in all treated plots using either the pure hydrocarbon, n-hexadecane, or the applied oils as the growth substrate. These increases were usually sustained throughout the year. Significant increases in hydrocarbon-utilizing fungi were not demonstrated by the plating technique used. The concentrations of residual oils or their oxidation products were of sufficient magnitude in the treated plots, 9 months after application, to cause significant inhibition of plant growth. From the data obtained, it was not possible to determine the type of compounds causing this inhibition or their long-term environmental effects. (+info)
An exocellular protein from the oil-degrading microbe Acinetobacter venetianus RAG-1 enhances the emulsifying activity of the polymeric bioemulsifier emulsan.
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The oil-degrading microorganism Acinetobacter venetianus RAG-1 produces an extracellular polyanionic, heteropolysaccharide bioemulsifier termed emulsan. Emulsan forms and stabilizes oil-water emulsions with a variety of hydrophobic substrates. Removal of the protein fraction yields a product, apoemulsan, which exhibits much lower emulsifying activity on hydrophobic substrates such as n-hexadecane. One of the key proteins associated with the emulsan complex is a cell surface esterase. The esterase (molecular mass, 34.5 kDa) was cloned and overexpressed in Escherichia coli BL21(DE3) behind the phage T7 promoter with the His tag system. After overexpression, about 80 to 90% of the protein was found in inclusion bodies. The overexpressed esterase was recovered from the inclusion bodies by solubilization with deoxycholate and, after slow dialysis, was purified by metal chelation affinity chromatography. Mixtures containing apoemulsan and either the catalytically active soluble form of the recombinant esterase isolated from cell extracts or the solubilized inactive form of the enzyme recovered from the inclusion bodies formed stable oil-water emulsions with very hydrophobic substrates such as hexadecane under conditions in which emulsan itself was ineffective. Similarly, a series of esterase-defective mutants were generated by site-directed mutagenesis, cloned, and overexpressed in E. coli. Mutant proteins defective in catalytic activity as well as others apparently affected in protein conformation were also active in enhancing the apoemulsan-mediated emulsifying activity. Other proteins, including a His-tagged overexpressed esterase from the related organism Acinetobacter calcoaceticus BD4, showed no enhancement. (+info)
Microbial degradation of oil spills enhanced by a slow-release fertilizer.
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The improved cleanup of marine oil spills by stimulating biodegradation through the use of a slow-release fertilizer is reported. A paraffin-supported fertilizer containing MgNH4PO4 as active ingredient was developed and evaluated in laboratory and field experiments using quantitative infrared spectrometry and chromatographic techniques. The biodegradation of Sarir crude oil in the sea was considerably enhanced by paraffin-supported fertilizer. After 21 days 63% had disappeared as compared to 40% in the control area. (+info)
Toxicity of flare and crude hydrocarbon mixtures.
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The toxicity of whole, saturate, and aromatic hydrocarbon mixtures from flare pit and crude oil sources were evaluated using Lumbricus terrestris. Body burden analysis was used to analyze the intrinsic toxicity of the six hydrocarbon mixtures. The major fractions of the whole mixtures, the saturate, and aromatic fractions had different intrinsic toxicities; the aromatics were more toxic than the saturates. The toxicity of the saturate and aromatic fractions also differed between the mixtures. The flare saturate mixture was more toxic than the crude saturate mixture, while the crude aromatic mixture was more toxic than the flare aromatic mixture. The most dramatic difference in toxicity of the two sources was between the flare whole and crude whole mixtures. The crude whole mixture was very toxic; the toxicity of this mixture reflected the toxicity of the crude aromatic fraction. However, the flare whole mixture was not toxic, due to a lack of partitioning from the whole mixture into the lipid membrane of the exposed worms. This lack of partitioning appears to be related to the relatively high concentrations of asphaltenes and polar compounds in the flare pit whole mixture. (+info)
Heat or eat? Cold-weather shocks and nutrition in poor American families.
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OBJECTIVES: The authors sought to determine the effects of cold-weather periods on budgets and nutritional outcomes among poor American families. METHODS: The Consumer Expenditure Survey was used to track expenditures on food and home fuels, and the Third National Health and Nutrition Examination Survey was used to track calorie consumption, dietary quality, vitamin deficiencies, and anemia. RESULTS: Both poor and richer families increased fuel expenditures in response to unusually cold weather. Poor families reduced food expenditures by roughly the same amount as their increase in fuel expenditures, whereas richer families increased food expenditures. CONCLUSIONS: Poor parents and their children spend less on and eat less food during cold-weather budgetary shocks. Existing social programs fail to buffer against these shocks. (+info)
Alkanindiges illinoisensis gen. nov., sp. nov., an obligately hydrocarbonoclastic, aerobic squalane-degrading bacterium isolated from oilfield soils.
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An alkane-degrading bacterium, designated GTI MVAB Hex1(T), was isolated from chronically crude oil-contaminated soil from an oilfield in southern Illinois. The isolate grew very weakly or not at all in minimal or rich media without hydrocarbons. Straight-chain aliphatic hydrocarbons, such as hexadecane and heptadecane, greatly stimulated growth; shorter-chain (+info)