Dose-Response Assessment of Airborne Methyl Isothiocyanate (MITC) Following a Metam Sodium Spill

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.     

A Characterization of a Matric-Variate Exponential Distribution

Suppose S is a positive definite m x m random matrix and S> Ω denotes the event that S—Ω is positive definite, Ω being a constant positive definite matrix. Under very mild regularity conditions, we show that the constraint Pr(S>Ω₁+Ω₂ | S>Ω₂) = Pr(S>Ω₁) implies that S has a Wishart distribution on m+ 1 degrees of freedom.     

Wirth,Whiskey, and WASP's: Some Consequences of Community Size for Alcohol Use*†

Several themes in Wirth's “Urbanism as a Way of Life” generate the prediction that alcohol use (versus nonuse) will be more widespread among residents of urban areas. Multiple regression analysis of data from two recent national polls (1966, 1968) reveals support for this prediction. With eight other key sociological variables simultaneously controlled, the greater the urbanism of a community (measured in terms of community size), the greater the proportion of alcohol users it contains. To make certain that this association is due to urban conditions (as opposed to merely the absence of rural forces which encourage abstinence), the effects of rural forces are reduced by omitting the most rural categories of the community size measure of urbanism, and the data are reexamined. The association still persists, basically because of the larger proportion of middle to upper status, white, and Protestant alcohol users in the more urban areas.     

Exploring the prevalence and correlates of methamphetamine use: findings from Sacramento's ADAM program

Anecdotal reports have suggested that the use and abuse of methamphetamine is increasing in the United States. To date, however, few scholarly works have explored the prevalence and correlates of methamphetamine use in the United States. To address this limitation, a secondary analysis was undertaken with data collected through the Arrestee Drug Abuse Monitoring (ADAM) Program. An examination of methamphetamine-positive rates among ADAM arrestees interviewed between 1991 and 2001 identified that its use is concentrated within the Western part of the United States. Supplementary analyses of Sacramento arrestees indicated that 71% were diagnosed as needing some form of alcohol or other drug treatment. Compared to those arrestees who were detected methamphetamine-negative, methamphetamine-positive arrestees in Sacramento were three times as likely to be white and to have been diagnosed in need of drug treatment. Implications for drug control policy are discussed.     

Colleges respond to student binge drinking: reducing student demand or limiting access

Administrators at 68% of 4-year colleges nationwide (N = 747) responded to a survey concerning the types of programs and policies they used in response to students' heavy drinking. Most schools conducted targeted alcohol education and invested in institutional prevention efforts; half conducted social norms campaigns; a sizeable minority restricted alcohol on campus. Schools that focused on demand reduction were less likely to ban alcohol use. One in 3 schools received funding for these programs from governmental agencies, and 1 in 5 from the alcohol industry. Such schools were more likely to conduct targeted alcohol education and social norms programs and were less likely to restrict alcohol use on campus or at college events. Colleges may want to reconsider prevention initiatives that focus exclusively on demand or supply. They may also want to examine the extent to which funding is the driving force shaping the direction of their alcohol initiatives.     

Facilitators and barriers to employment: the perspectives of people with psychiatric disabilities and employment service providers

This study examined the perspectives of people with psychiatric disabilities and employment service providers regarding factors that most directly help or hinder consumer efforts to obtain and maintain employment. Forty-four adults with serious mental illness (SMI) (consumers) and 30 providers participated in 12 focus groups across Massachusetts. We began both consumer and provider groups by posing two broad questions: 1) what factors most help people with SMI get and keep jobs (facilitators), and 2) what factors most prevent people with SMI from getting and keeping jobs (barriers)? Data were analyzed qualitatively and both person and environmental factors were highlighted. Among facilitators, participants agreed that quality consumer-provider relationships and individualized employment services are most instrumental in helping consumers achieve employment goals. Participants identified a range of environmental barriers, including issues related to the service system, entitlement programs, non-human resources, and social stigma. Implications for services are discussed.     

Prospect Theory and Limit Lines

Risk acceptance criteria in the form of limit lines are investigated in the context of prospect theory. This theory departs from utility theory in several respects, an important one being the use of weights other than probabilities in the evaluation of the expected impact of uncertain outcomes. Hypothetical functions reflecting certain attitudes toward consequences and rare events are developed and combined to produce several limit lines.     

Guns and gun threats at college

A random sample of more than 10,000 undergraduate students, selected from 119 4-year colleges, answered a mailed questionnaire about gun possession and gun threats. Approximately 4.3% of the students reported that they had a working firearm at college, and 1.6% of them have been threatened with a gun while at school. Students are more likely to have a firearm at college and to be threatened with a gun while at college if they are male, live off campus, binge drink, engage in risky and aggressive behavior after drinking, and attend institutions in regions of the United States where household firearm prevalence is high. Having a firearm for protection is also strongly associated with being threatened with a gun while at college. Students who reported having firearms at college disproportionately reported that they engaged in behaviors that put themselves and others at risk for injury.