Exposure of healthy subjects with emissions from a gas metal arc welding process: part 1--exposure technique and external exposure.

BACKGROUND: Studies concerning welding fume-related adverse health effects in welders are hampered by the heterogeneity of workplace situations, resulting in complex and non-standardized exposure conditions. METHODS: In order to carry out welding fume exposure studies under controlled and standardized conditions, the Aachen Workplace Simulation Laboratory was developed. This laboratory consists of an emission room, in which welding fume is produced, and an exposure room in which human subjects are exposed to these fumes. Both rooms are connected by a ventilation system which allows the welding fume concentration to be regulated. Particle mass concentration was measured with a TEOM microbalance and the particle number-size distribution using a Grimm SMPS device. RESULTS: In a study, which is the subject of this paper, it has been shown that welding fume concentration can easily be regulated between 1 and about 3 mg m(-3). The chosen concentration can be kept constant for more than 8 h. However, transport of the particles from the emission room into the exposure room leads to a change in particle size distribution, which is probably due to coagulation of the fraction of smallest particles. CONCLUSION: The Aachen Workplace Simulation Laboratory is suitable for controlled exposure studies with human subjects.

Health education in medical group practices: promoting health or business?

This article attempts to explain differences in the health education activities of medical group practices. Potential explanatory factors examined include: providing prepaid care, group ownership, group size, and specialty composition and mechanism for making group policy. The data used in this analysis were collected by the American Medical Association through the 1986 National Survey of Medical Groups. Results indicate that the conduct of a variety of health education activities was determined primarily by the group's policy mechanism. That groups with more formal policy mechanisms are more likely to conduct health education activities suggests that the provision of health education is a business decision rather than a medical one. Some implications for health educators of the use of health education to promote a practice are discussed.

Sex differences in the use of alcohol and tranquilizers: testing a role convergence hypothesis.

Research on adult alcohol and tranquilizer use provides strong evidence of fundamental sex differences in the use of the two types of drugs. Current explanations posited for these differences center around differential sex roles and sex role expectations. Much of the discussion of these differences suggests that as male and female roles converge, these behavioral differences should decrease. Using data from a statewide survey of Illinois adults, we provide a preliminary test of a sex role convergence hypothesis for alcohol and tranquilizer use. To do so, we use a multinomial extension of logistic multiple regression. After controlling for demographic and sex role characteristics, the results show that females have a much higher probability of using tranquilizers rather than alcohol than men do. Thus, the role convergence hypothesis is not supported for the use of these two types of drugs.