Table 1

Characteristics of person-years (percentages) according to cumulated styrene exposure level among 59 997 male and 12 215 female workers in the Danish reinforced plastics industry, 1979 to 2012

Worker characteristics	Men			Women
	Cumulated styrene exposure level (mg/m³-years)			Cumulated styrene exposure level (mg/m³-years)
	≤17	18–67	≥68	≤17	18–67	≥68
	367 861 person-years	438 164 person-years	456 872 person-years	137 002 person-years	67 056 person-years	48 171 person-years
Occupation*†
White collar workers	20	14	16	37	28	25
Skilled blue collar workers	26	32	32	3	2	2
Unskilled blue collar workers	42	35	37	37	40	46
Others/unknown	12	19	15	23	30	27
Education*‡
Secondary education	41	39	39	49	51	55
Vocational education	41	40	41	34	30	26
Short-cycle higher education	4	3	3	4	3	3
Medium-or long-cycle higher education	8	9	6	8	7	5
Unknown	6	9	11	5	9	11
Age (years by 1 November each year)
≤39	43	32	28	40	32	26
40–49	28	28	26	29	28	26
50–59	19	23	24	19	23	24
60–69	8	12	15	9	12	16
≥70	2	5	7	3	5	8
Calendar year of follow-up*
1979	1	2	2	1	2	2
1980–1989	9	21	28	11	23	28
1990–1999	22	32	33	24	30	34
2000–2009	50	35	29	48	35	29
2010–2012	18	10	8	16	10	7

*Age standardised.
†Grouped according to the Danish version of ISCO-88.
‡Highest completed education according to The Populations' Education Register (1981–2011).
ISCO-88, International Standard Classification of Occupations 1988.