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The long-term health consequences of exposure to phenoxyherbicides used in Vietnam has been a great concern to the veterans. In addition to the Air Force Ranch Hand personnel, Army Chemical Corps personnel who served in Vietnam are thought to have had some of the highest herbicide exposures. The Department of Veterans Affairs commenced a study of veterans who served in Vietnam as members of the Army Chemical Corps and a comparison cohort of Army Chemical Corps personnel who served elsewhere. A total of 2872 Vietnam veterans and 2737 non-Vietnam veterans who served in the Army Chemical Corps were identified for inclusion in a telephone health interview survey with a random 20% sample of veterans receiving serum dioxin and other congeners assessments. In a feasibility study which included 284 Vietnam veterans and 281 non-Vietnam veterans, 100 serum assessments were conducted of which 95 were included in the analysis. Vietnam veterans with a history of spraying herbicides were found to have a statistically significant elevation in their current serum 2,3,7,8-TCDD concentrations compared to non-Vietnam veterans without a spray history (P = 0.05). Other 2,3,7,8-substituted dioxins levels were comparable to the levels found in the non-Vietnam veterans. This feasibility study demonstrated that serum dioxin concentrations from a sample of the study participants can be used to identify exposure variables in the health survey that can serve as a surrogate measure of phenoxyherbicide exposure.

Carbonless copy paper (CCP), introduced in 1954, is ubiquitous in the U.S. marketplace, and because of this, many workers come into contact with it. Its safety to workers who handle large amounts of CCP has been addressed in numerous studies and reports; and the National Institute for Occupational Safety and Health (NIOSH) on two occasions has sought to determine what, if any, hazards to health CCP might pose. This review encompasses the world's literature on CCP and provides a weight-of-evidence analysis of the safety of CCP to workers in the United States. CCP is systematically studied on large groups of humans using repeat insult patch tests. Consistently, CCP in U.S. commerce since 1987 (the focus of this review) has produced neither primary skin irritation nor skin sensitization under exaggerated test conditions, demonstrating that no irritation or sensitization is expected on contact with CCP under normal conditions of manufacture and use. Years after the introduction of CCP, the first case reports appeared in 1974 suggesting an association between CCP use and various generic symptoms. Most of the earliest reports occurred in Sweden in response to negative publicity concerning the product, and to date approximately half of all published articles originate in Scandinavia. Many early reports were questionnaire/interview studies which suffered from suggestive questions, biases, and lack of control for confounding factors. Few studies included a comparison group (i.e., people not exposed to CCP) making it impossible to estimate risk values. Later, sick building syndrome studies, accounting for many relevant factors in the office environment, found no association between CCP exposure and symptoms unexplained by other factors. Animal studies showed that compounds used to manufacture CCP do not have acute toxic potential and are not genotoxic. Finally, very few published complaints have come from the manufacturing sector where the closest and most voluminous contact occurs. A few reports of symptoms have emanated from printing facilities (with a multiplicity of other chemical exposures), but generally most symptoms are reported in the office setting where the exposure is lower than in the manufacturing or printing settings. Based on the weight of the evidence, CCP currently in commerce in the United States is shown not to be the causative agent for the reported general symptoms sometimes associated with it over the years. Recently NIOSH evaluated the literature as to possible hazards to health posed by CCP, and NIOSH is anticipated to conclude that CCP is not a hazard to workers and has only a small possibility of producing mild and transient skin irritation., (Copyright 2000 Academic Press.)

This case-control study examines potential associations between telephone linework and the occurrence of leukemia except chronic lymphocytic leukemia in a primarily retired population of American Telephone and Telegraph Company (AT&T) workers. Cases died between 1975 and 1980. Exposure is defined both by job title and, for workers with complete job histories, by a lifetime exposure score based on industrial hygiene personal monitoring measurements of line and nonline jobs. When the time-weighted average mean for each job is accumulated into a lifetime exposure score, workers with scores above the median for the population show an excess of leukemia 2.5 times higher than workers below the median (95% confidence interval (CI) 0.7-8.6). Those individuals with long duration of employment in jobs with intermittent peak exposures may be at higher risk of leukemia than those with a constant exposure level. Analyses that allow for a latent period suggest the risk is associated with exposures that occurred 10 or more years before death. Workers with peak exposure scores above the median have odds ratios of 2.4 (95% CI 0.7-9.0) and 6.6 (95% CI 0.7-58) for latent periods of 10 and 15 years, respectively. The data suggest an increasing risk with increasing exposure (p for trend = 0.05) when cumulated scores are based on peak exposure scores. Peak exposures tended to occur in cable splicing work and in old telephone switching offices. The numbers in this study are small and observed differences may be due to chance.

1,3-Butadiene and styrene are suspected carcinogens and common chemicals used in the synthesis of rubber. To investigate any potential human hazards from exposure to these chemicals, a case-control study of 59 lymphohematopoietic cancers was conducted within a cohort of male workers employed between 1943 and 1982 in eight North American styrene-butadiene rubber polymer-producing plants. A total of 193 controls were matched to the cases by plant, age, year of hire, duration worked, and survival to time of death of the case. Each job was assigned an estimated exposure rank, and each worker's cumulated rank score was calculated on the basis of the time spent in each job throughout his employment. "Exposure" as a dichotomous variable was defined as a log rank score above the mean of the log scores for the total population of cases and controls within a subtype of cancer. Matched-pair analysis identified a strong association between leukemia and butadiene, with an odds ratio of 9.36 (95% confidence interval 2.05-22.9) and an association between styrene and leukemia (odds ratio = 3.13, 95% confidence interval 0.84-11.2) that did not achieve statistical significance. When exposure to both styrene and butadiene was included in a conditional logistic regression model, the odds ratio for butadiene remained high (odds ratio = 7.39), but the estimated association of leukemia with styrene was small. The results of this study support the hypothesis that exposure to butadiene is associated with the risk of leukemia. There also appears to be an additional risk from work in specific subdivisions of the industry.

This study evaluated risk factors for injurious and noninjurious slips, trips, and falls among painters and investigated the hypothesis that exposure to solvents influenced the risk of such accidents. The data were collected longitudinally over an 11 month period. Weekly self-administered questionnaires detailed paint solvent exposure; work-related slips, trips, and falls (STFs); and potentially hazardous job tasks and environmental conditions. An initial questionnaire ascertained personal data, such as age, solvent exposure history, and alcohol consumption. During the study, 2,088 person-weeks of data were collected. Some participants provided many weeks of data, while others responded sporadically. Exposure to potentially hazardous environmental conditions was significantly related to the occurrence of STFs during a week. Several measures of solvent exposure were evaluated for their effect on STFs. Low solvent exposure during a week significantly increased the occurrence of slips, trips, and falls compared to no exposure. Moderate and high weekly exposure were not associated with increased risk, however. Week-to-week variability in the amount of solvent exposure was a strong positive predictor of STFs. Further analysis showed that both increases and decreases in solvent exposure between the preceding 2 weeks and the week of the STF were positively related to the risk of such events. The strongest effect was observed for exposure increases over the preceding 2 weeks. Overall, the results suggest that solvent exposure variability may increase accident risk, and possible explanations are explored.