There have been few attempts to assess the validity of occupational histories obtained from interviews. A nested case-control study of lung cancer conducted in 1985 among a cohort of 19,608 male workers at a Texas chemical production facility provided such an opportunity. Telephone interviews were attempted with 308 lung cancer patients and 588 matched controls or their next of kin in order to gather information on tobacco use, diet, places of residence, and occupations. Interview data from 734 respondents (143 subjects and 591 next of kin) were then compared with the records of work area assignments maintained by the company and with exposure profiles developed by an industrial hygienist. Respondents recalled 48.4 per cent of all documented work area assignments, but only 2.6 per cent of the chemical agents judged as likely exposures. Recall of usual work area assignment was 70.8 per cent. Among the factors found to have most influenced recall were the number and durations of assignments, a subjective assessment of the quality of the interview, and the relationship of the interview respondent to the subject. The elapsed time from job assignment to interview was also found to affect recall of the longest assignment of the subject.

Mortality was updated to the end of 1982 for 594 employees exposed to benzene who had been studied previously and for an additional 362 exposed workers not studied previously. Cause specific mortality comparisons were made using United States white male, age, and calendar year adjusted rates. Total mortality was observed to have been significantly below expectation, and this was particularly evident for deaths from accidental causes. Mortality from skin cancer was significantly raised, although there were no unusual or common characteristics among the affected individuals which would suggest a link with exposure to benzene. A non-significant excess of total deaths from leukaemia was noted based on four observed cases; however, all four were myelogenous leukaemias and this represented a significant excess in that subcategory. These and other deaths of possible interest are reviewed in detail. Analyses by work area, duration of exposure, and cumulative dose index did not show patterns suggestive of a causal association between exposure to benzene and any particular cause of death.

The mortality experience of 371 employees assigned to acrylamide monomer and polymerisation operations was examined with particular emphasis on cancers at sites identified from animal studies such as the central nervous system, thyroid gland, other endocrine glands, and mesotheliomas. A total of 29 deaths was observed up until 1982 (38-0 expected). No statistically significant excesses were noted in the total cohort and no deaths were found for the hypothesised sites of cancer. The observed deaths in the total cohort for the all cancers category were somewhat in excess (11 v 7-9); however, this was due entirely to excess cancers of the digestive tract and respiratory system in the subgroup with previous exposure to organic dyes. Among those employees not exposed to organic dyes, four deaths were due to malignancies versus 6-5 expected. This study does not support a cause effect relation between exposure to acrylamide at this work site and overall mortality, total malignant neoplasms, or any specific cancers.Acrylamide is a white crystalline solid which is important as a chemical intermediate and as a monomer used in the production of polyacrylamides. The effects of exposure to acrylamide have been reported to include peeling and redness of the skin of the hands, localised numbness of the legs, excessive sweating of the feet and hands, and both central and peripheral nervous system damage.' Epidemiological studies of employees exposed to acrylamide have not been published to date.The chronic effects of acrylamide in rats have been investigated in a two year toxicity-oncogenicity study.2 Fischer 344 rats were divided into groups of 90 rats by sex and dose level and given water formulated to provide 0. 0-01, 0 1, 0 5, and 2-0 mg/kg/day of acrylamide. Histopathological examination indicated that in the female rats at the highest dose level there was a statistically significant increase in the number of neoplasms of the mammary gland, nervous system, clitoral gland, uterus, oral cavity, and thyroid gland. Data from male rats indicated an increased incidence of mesothelioma in the scrotal cavity at dosages of 0-5 and 2-0 mg/kg/day. The incidence of benign tumours of the thyroid gland was also statistically increased at doses of 2-0 mg/kg/day. Although not statistically significant, there appeared to be an increased incidence of tumours in the brain and spinal cord at the highest level in the male rats.2

BOND GG, BODNER KM, OLSEN GW, COOK RR. Mortalit y among wor kers engaged in the development or manufactu re of styrene-based produ cts -an update . Scand J Work Environ Health 1992; 18:145-54. Mortality was updated another 11 years through 1986 for a pr eviously studied cohort of 2904 male chemical workers who were potent ially exposed to styrene and related materials for a year or more between 1937 and 1971. Substantial deficits in mortality from all causes and total cancer were observed in the cohort when it was compared with white males in the United States, and also other chemical worker s who were unexposed to styrene-based products. Mortality from leukemia was slightly less than expected during the updated period , in contrast to an excess of lymphatic leukemia observed in the original period. Yet small elevations in risk of other types of lymphatic cancer, particularly multiple myeloma, persisted. The risk of these cancers did not increase with estimated inten sity or duration of styrene exposure. The findings are discussed in context with those of studies of similarly exposed workers in related industries.

A recent cohort mortality study of male, hourly wage employees of a large Michigan chemical production and research facility had found a greater than expected number of deaths coded to liver and biliary tract cancer. In response, an additional investigation was then undertaken of the 44 liver and biliary tract cancer deaths observed between 1940 and 1982. A random sample (N = 1,888) of subjects was selected from the total cohort (N = 21,437) to serve as referents. Company work history records were used to classify cases and referents by work area assignment and potential for exposure to 11 selected chemical agents which have been shown to produce cancer of the liver or biliary passages in experimental animals. Statistically significant associations in both positive and negative directions were found for several work areas within the facility. A suggestive association was found for vinyl chloride monomer, based on five cases with presumed exposure.