Reproductive and Developmental Risks from Ethylene Oxide: A Probabilistic Characterization of Possible Regulatory Thresholds

Ethylene oxide is a gas produced in large quantities in the United States that is used primarily as a chemical intermediate in the production of ethylene glycol, propylene glycol, non-ionic surfactants, ethanolamines, glycol ethers, and other chemicals. It has been well established that ethylene oxide can induce cancer, genetic, reproductive and developmental, and acute health effects in animals. The U.S. Environmental Protection Agency is currently developing both a cancer potency factor and a reference concentration (RfC) for ethylene oxide. This study used the rich database on the reproductive and developmental effects of ethylene oxide to develop a probabilistic characterization of possible regulatory thresholds for ethylene oxide. This analysis was based on the standard regulatory approach for noncancer risk assessment, but involved several innovative elements, such as: (1) the use of advanced statistical methods to account for correlations in developmental outcomes among littermates and allow for simultaneous control of covariates (such as litter size); (2) the application of a probabilistic approach for characterizing the uncertainty in extrapolating the animal results to humans; and (3) the use of a quantitative approach to account for the variation in heterogeneity among the human population. This article presents several classes of results, including: (1) probabilistic characterizations of ED10s for two quantal reproductive outcomes-resorption and fetal death, (2) probabilistic characterizations of one developmental outcome-the dose expected to yield a 5% reduction in fetal (or pup) weight, (3) estimates of the RfCs that would result from using these values in the standard regulatory approach for noncancer risk assessment, and (4) a probabilistic characterization of the level of ethylene oxide exposure that would be expected to yield a 1/1,000 increase in the risk of reproductive or developmental outcomes in exposed human populations.     

福特复活“探险者”

在suvN靡美国的90年代，福特探险者是当时的销量冠军，每年狂销几十万辆。但是随着高油价和环保时代的到来，探险者便一蹶不振了。在去年的旧车换现金计划中，报废的探险者比其他车型都要多。     

Encyclopaedic Desire: A Response to Gates

“We Spend Our Years as a Tale That Is Told”: Oral Historical Narrative in a South African Chiefdom by Isabel Hofmeyr. Portsmouth, NH: Heinemann; Johannesburg: Witwatersrand University Press; London: James Currey, 1994.

Liquor and Labour in Southern Africa, edited by Jonathan Crush and Charles Ambler. Athens: Ohio University Press; and Pietermaritzburg: University of Natal Press, 1992.

Politics and performance: Theatre, Poetry, and Song on Southern Africa, edited by Liz Gunner, Johannesburg: Witwatersrand University Press, 1994.

In the Wake of the Affluent Society: An Exploration of Post‐Development by Serge Latouche; translated and introduced by Martin O'Connor &; Rosemary Arnoux; London: Zed, 1993.     

Seat belt laws: why we should keep them

In the June 2007 issue of Significance , John Adams argued for the repeal of seat belt laws. They have never been demonstrated to save lives, he said; and they increase the number of pedestrians and cyclists killed on the roads. Richard Allsop, Oliver Carsten, Andrew Evans and Robert Gifford argue that Parliament should keep the seat belt laws on the statute book and that we should all keep wearing belts whenever we travel in a car, van or coach—and they contest John's statistics.     

Evaluating the Efficacy of a Mental Models Approach for Improving Occupational Chemical Risk Protection

Chemical risk protection in the workplace relies partly on informing workers about possible risks using material safety data sheets (MSDS). This article reports on phase 2 of a project (phase 1 reported in Cox et al.), which employed a mental models approach to improve on data sheets as communicative interventions for perchloroethylene in dry cleaning and rosin-based solder flux in the electronics industry within small businesses in the United Kingdom (small enterprises (SEs) < 25 employees in the workplace). It focuses on the efficacy of a multimethod evaluation strategy to assess (1) the capacity of a mental models approach to yield contextually relevant data for intervention design and (2) the effectiveness of the strategy itself in validating the mental models data. The evaluation was conducted using postal questionnaires and semi-structured verbal protocols to provide responses to the alternative intervention content and to prioritize risk messages. User discussion groups were then employed, particularly as a means of establishing whether contextual information could be obtained that would differ qualitatively from the kind elicited through individual (semi) structured methods. We conclude that the mental models approach as part of an iterative process including systematic multimethod evaluation is successful in supporting the design of relevant communications to the users of chemicals. The overall viability of communicative interventions in the context of health and safety in small businesses remains in question. Future research might aim to develop a more holistic approach to interventions in complex occupational contexts.     

Whom can you trust? The politics of ‘grassing’ on an inner city housing estate

This paper derives from an ongoing research project concerned to explore how people living in, going to work in, attending school in, high crime areas manage their routine daily lives. It focuses on one of our research areas in which we argue that the question of the 'fear of crime' is much better understood through an appreciation of how the question of trust manifests itself in that community. In other words, whom you trust, when, and by how much, mediate the way in which people living in this area manage their routine daily lives and within that their sense of security.