Table 5.

Occurrence of pleural plaques among males exposed to mineral wool.

		Exposed to mineral wool			Not exposed
Age group (years)	Workers	Workers with plaques	Frequency (%)	Referents	Referents with plaques	Frequency (%)
20–29	202	0	0.00	159	0	0.00
30–39	215	1	0.47	136	0	0.00
40–49	138	2	1.45	107	0	0.00
50–59	122	6	4.92	86	2	2.33
60–69	77	3	3.90	53	1	1.89
All	754	12	1.59	541	3	0.55

Summary of data from Järvholm et al. (1995).