Mortality patterns in eight U. K. oil refineries.

The patterns of mortality are described for 35,000 male employees, with a minimum of 1 year's continuous service, who worked at 8 refineries in the U. K. in the period 1 January 1950-31 December 1975. The trace rate of those involved was 99.8%. Overall the ratio of observed to expected deaths was 0.84 (O = 4406, E = 5259.9 P less than 0.00001). The numbers of deaths for many of the chronic degenerative diseases were lower than "expected." The number of observed deaths from all cancers were appreciably less than expected (O = 1147, E = 1286.4, O/E = 0.89, P = 0.00006). Lung cancer was particularly reduced (O = 416, E = 532.7, O/E = 0.78, P less than 0.00001); there was no excess of leukemia ( in workers including some exposed to benzene). Other comparable studies have suggested an excess of gastrointestinal cancer. In the present study deaths from esophageal, stomach, intestinal, and rectal cancer were slightly raised for all workers (O = 346, E = 328.6, O/E = 1.05, P less than 0.4); this was particularly true for those joining before 1950 with long service and increased latent interval. There were also excesses based on small numbers of deaths from nasal cancer (O = 7, E = 3.1, O/E = 2.24, P less than 0.05), and melanoma (O = 14, E = 6.5, O/E = 2.16, P less than 0.01). There was no evidence of an excess of brain tumors (O = 36, E =- 44.8, O/E = 0.80, P less than 0.2).