Table 2

Observed deaths (Obs), expected deaths (Exp), relative risks (RR) stratified by age, calendar year, and pay status, and standardised mortality ratios (SMR) for selected causes among male employees with likely exposure to higher chlorinated dioxins, compared to unexposed plant workers and the US population

		RR			SMR
Cause of death (ICDA-8), Exposure category	Obs	Exp	RR	95% CI	Exp	SMR	95% CI
All malignant neoplasms (140–209)
Background	2489		1.0		2649.1	0.9	0.9 to 1.0
Very low	19	18.8	1.0	0.6 to 1.6	20.6	0.9	0.6 to 1.4
Low	44	42.0	1.0	0.8 to 1.4	46.0	1.0	0.7 to 1.3
Moderate	52	47.7	1.1	0.8 to 1.4	51.4	1.0	0.8 to 1.3
High	27	29.5	0.9	0.6 to 1.3	31.7	0.9	0.6 to 1.2
Very high	26	19.2	1.4	0.9 to 2.0	20.8	1.3	0.8 to 1.8
p value for linear trend			0.33

Cancer of the lung (162)
Background	843		1.0		893.0	0.9	0.9 to 1.0
Very low	4	6.5	0.6	0.2 to 1.6	7.2	0.6	0.2 to 1.4
Low	18	14.6	1.2	0.8 to 2.0	16.2	1.1	0.7 to 1.7
Moderate	15	16.3	0.9	0.6 to 1.5	17.7	0.9	0.5 to 1.4
High	6	10.4	0.6	0.3 to 1.3	11.2	0.5	0.2 to 1.2
Very high	5	6.8	0.7	0.3 to 1.8	7.4	0.7	0.2 to 1.6
p value for linear trend			0.27

Soft tissue sarcoma (171)
Background	18		1.0		11.8	1.5	0.9 to 2.4
Very low	0	0.2	0.0	NA	0.1	0.0	0.0 to 33.5
Low	0	0.4	0.0	NA	0.3	0.0	0.0 to 14.8
Moderate	0	0.4	0.0	NA	0.3	0.0	0.0 to 14.8
High	0	0.2	0.0	NA	0.1	0.0	0.0 to 26.3
Very high	2	0.1	15.8	5.2 to 47.8	0.1	21.8	2.7 to 80.2
p value for linear trend			0.07

Non-Hodgkin’s lymphoma (200, 202)
Background	82		1.0		84.7	1.0	0.8 to 1.2
Very low	2	0.7	3.1	0.8 to 11.6	0.7	2.8	0.3 to 10.0
Low	1	1.4	0.7	0.1 to 4.9	1.6	0.6	0.0 to 3.4
Moderate	2	1.7	1.2	0.3 to 4.9	1.7	1.2	0.1 to 4.2
High	2	1.0	2.1	0.5 to 8.3	1.1	1.9	0.2 to 6.9
Very high	1	0.6	1.7	0.2 to 11.9	0.7	1.5	0.0 to 8.3
p value for linear trend			0.31