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961.
Dose-Response Assessment of Airborne Methyl Isothiocyanate (MITC) Following a Metam Sodium Spill 总被引:3,自引:0,他引:3
George V. Alexeeff Dennis J. Shusterman Robert A. Howd Richard J. Jackson 《Risk analysis》1994,14(2):191-198
A tank car derailment in northern California in 1991 spilled metam sodium into the Sacramento River, and released its breakdown product, methyl isothiocyanate (MITC), into the air. This paper describes the risk evaluation process used. Over 240 individuals reported symptoms such as eye and throat irritation, dizziness, and shortness of breath. Reference exposure levels (RELs) for 1 hr were developed for MITC and compared to exposure concentrations. Ocular irritation in cats was the most sensitive endpoint reported. The no observed adverse effect level (NOAEL), divided by an uncertainty factor (UF) of 100, produced an REL of 0.5 ppb of MITC in air to prevent discomfort. An REL to prevent disability was estimated to be 40 ppb. An REL to prevent life-threatening injury was estimated to be 150 ppb. Measured MITC levels ranged from 0.2-37 ppb and estimated peak levels ranged from 140-1600 ppb. The usefulness of RELs for emergency planning is discussed. 相似文献
962.
R W Hart S C Freni D W Gaylor J R Gillette L K Lowry J M Ward E K Weisburger P Lepore A Turturro 《Risk analysis》1986,6(2):117-154
The Color Additives Scientific Review Panel considered whether there was information sufficient to perform a carcinogenic risk assessment on the colors D&C Red No. 19 (R-19), D&C Red No. 37 (R-37), D&C Orange No. 17 (O-17), D&C Red No. 9 (R-9), D&C Red No. 8 (R-8) and FD&C Red No. 3 (R-3) and to evaluate the assessments sent to FDA as part of the petitions for use of the colors for drug and external uses by the Cosmetic, Toiletry and Fragrance Association (CTFA). There is a lack of human data concerning the colors for making a human health assessment, so the assessments are based upon the extrapolation of animal data. The risk assessments are determined for exposure to single chemicals. Excluded from consideration are possible effects from exposure to multiple chemicals, such as co-carcinogenesis, promotion, synergism, antagonism, etc. In the light of recent efforts in establishing a consensus in risk assessment, the Panel has determined that the CTFA assessments for R-10, O-17, and R-9 are consistent with present acceptable usages, although it questions some of the assumptions used in the assessments. The Panel identified a number of general assumptions made, and discusses their validity, their impact on total uncertainty, and the potential options to address the gaps in understanding that necessitate the assumption. The Panel also derived revised risk estimates using more "reasonable" assumptions than "worst-case" situations, for 90th percentile and average exposure. For those assumptions that are easily quantifiable, the Panel's estimates are less than an order of magnitude lower than the CTFA risk estimates, indicating that the underestimates and overestimates of the CTFA risk estimates tend to balance each other. The impact of most of the assumptions is not quantifiable. The assessment for R-3 is complicated by the fact that there is no good skin penetrance study for this color. It was assumed that the penetrance is similar to that of another water-soluble xanthene color, R-19. It is expected that the absorption of the color is not likely to exceed that of the smaller molecule, R-19. Therefore, the risk estimates are similar to the CTFA estimates, but with different reasoning. The estimates for R-8 and R-37 are different from the others in that there is a lack of any exposure or toxicological information on these colors.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
963.
964.
This paper surveys the application of U.K. monopoly policy and examines its general impact on industrial structure and market processes. It considers the effects of the Competition Act 1980 in relation to U.K. monopoly control and concludes that unless further measures are introduced, competitive pressures are likely to be weakened over the longer term. 相似文献
965.
Laura Bragg, a member of the first graduating class at Simmons College, journeyed to Charleston as a New Woman in 1909. As the first woman director of a major scientific museum in the United States, Bragg transformed the Charleston Museum into a public education institution and became an innovative leader in museum education. This article documents Bragg's contributions within the context of antebellum culture where the Southern Belle was placed on a Victorian pedestal and Boston marriages were an unknown phenomenon. Using extensive and hitherto unpublished correspondence, the authors detail Bragg's lesbian relationships and describe her network within the homosexual male community during the era of the Charleston Renaissance. 相似文献
966.
Younger women, relative to older women, incur elevated risk of uxoricide-being murdered by their husbands. Some evolutionary theorists attribute this pattern to men's evolved sexual proprietariness, which inclines them to use violence to control women, especially those high in reproductive value. Other evolutionary theorists propose an evolved homicide module for wife killing. An alternative to both explanations is that young women experience elevated uxoricide risk as an incidental byproduct of marriage to younger men who commit the majority of acts of violence. We used a sample of 13,670 uxoricides to test these alternative explanations. Findings show that (a) reproductive-age women incur an elevated risk of uxoricide relative to older women; (b) younger men are overrepresented among uxoricide perpetrators; and (c) younger women, even when married to older men, still incur excess risk of uxoricide. Discussion examines competing explanations for uxoricide in light of these findings. 相似文献
967.
Siegel JA 《Violence and victims》2000,15(3):235-255
Although research shows that sexually abused children appear to be at risk of subsequent aggressive behavior, few investigations address whether such behavior persists beyond childhood. This research describes the self-reported adolescent and adult fighting behavior of 136 women sexually abused as children and examines the role of intervening variables in the risk of such behavior. The women are part of a longitudinal study of 206 primarily low-income, urban women whose abuse was documented at the time it occurred. Fighting was common, particularly during adolescence. Adult aggression was strongly associated with being a victim of violence by an intimate partner. A history of exposure to other forms of violence significantly increased the risk of fighting while strong maternal attachments mitigated the risk, primarily by reducing the likelihood of involvement in an abusive intimate relationship. 相似文献
968.
969.
970.
Next to doing nothing, fixing a problem is often the worst thing you could do with it. Fix a problem but miss the context, and you still have the problem--only it's bigger, it's weirder, it costs more, and everybody's grumpy. When something comes at you with a "problem" label, use it as an opportunity to connect things up, to explore, to ask the bigger questions, to find the new possibilities. When we react to a problem, we put ourselves into a dilemma. To find fruitful and creative solutions, we need to be in a place of choice, with many possibilities. Real participation--giving people real choice--is the only way you can bring people's intelligence and life experiences to bear on the situation at hand. 相似文献