Table 1

Sex, age, duration of employment in animal feed industry, and smoking

Workplace (people tested)		Sex				Age			Duration of employment in animal feed industry		Smoking
Workplace (people tested)		F	M			Mean	Range		⩽10 y	>10 y	n	%
Factory 1 (n=37):
Process (n=26)	2	24		44.0	23–59		8	18	10	38
Office (n=11)	7	4		43.6	30–57		2	9	5	45
Factory 2 (n=49):
Process (n=33)	1	32		42.5	29–59		7	26	13	39
Office (n=16)	8	8		37.8	23–56		8	8	5	31
Factory 3 (n=79):
Process (n=43)	12	31		40.7	21–58		19	24	17	39
Office (n=36)	12	24		41.5	28–59		20	16	11	31
Factory 4 (n=53):
Process (n=38)	4	34		45.9	22–60		10	24	14	37
Office (n=15)	5	10		43.8	33–58		6	4	4	27