Table 5.

Hazard Ratios for Acrylonitrile Exposure Lagged 10 Years and Risk of Lung Cancer for Workers by Strata of Asbestos Exposure Probability Score^a,b for Workers Employed at 8 Acrylonitrile-Producing Facilities, United States, 1952–2011

Cumulative AN Exposure, Lagged 10 Years, ppm-year	Asbestos Exposure Probability Scorec
	0			1–3			4–5
	No. of Deaths	HR	95% CI	No. of Deaths	HR	95% CI	No. of Deaths	HR	95% CI
Unexposed	228	1.00	Referent	12	0.91	0.50, 1.63	20	1.13	0.71, 1.80
0–0.09	90	1.20	0.93, 1.54	5	0.51	0.21, 1.25	14	1.73	1.00, 2.98
>0.09 but ≤0.64	74	0.91	0.70, 1.19	17	0.97	0.59, 1.61	18	1.42	0.87, 2.30
>0.64 but ≤2.30	52	0.85	0.63, 1.16	26	1.35	0.89, 2.05	31	1.32	0.90, 1.95
>2.30 but ≤12.10	60	0.98	0.73, 1.31	16	0.99	0.60, 1.66	33	1.39	0.95, 2.02
>12.10	45	1.63	1.17, 2.26	13	1.31	0.74, 2.30	51	1.39	1.01, 1.90

Abbreviations: AN, acrylonitrile; CI, confidence interval; HR, hazard ratio.

^a Internal comparisons use age as the time metric and are adjusted for race, sex, birth year, and salary-wage classification.

^b There were 549 lung cancer deaths with probability score of 0, 89 with a probability score of 1–3, 167 with a probability score of 4–5, and 3 lung deaths assigned as unknown.

^cP for interaction between cumulative AN and asbestos exposure probability is based on likelihood ratio test = 0.65.