A Group 1 carcinogen: cancer of the skin; Two large surveillance programs (1911-1938 and 1946-1996) found an increased risk of skin cancer among coal-tar distillers. In the earlier study, more than 700 skin cancers were attributed to coal tar exposure, and crude mortality rates for scrotal skin cancer were very high. [Reference #1] "These evaluations were typically produced at a time when the available data provided a clear indication of increased cancer risk in an occupational group, but not enough information to identify a causal agent. While such broadly defined carcinogenic agents can lead to general industrial hygiene interventions, provide support to compensate exposed workers and stimulate research to identify specific causes, they have limited utility for informing specific prevention activities and may be affected by changes in process, materials and exposure levels over time." [
PMID 29769352]