Table 2.

Aerosol exposure of grain and animal feed industry workers in Norway not using respiratory protective equipment

Aerosol exposure	All job groups	Grain elevator	Compound feed mill	Grain elevator and feed mill	Grain transport
N	56	28	17	6	5
Grain dust (mg/m3)
GM (GSD)	1.0 (2.9)	0.9 (2.5)a	1.6 (4.0)abc	0.5 (1.8)c	0.5 (2.0)b
25th centile	0.5	0.6	0.6	0.3	0.3
75th centile	2.0	1.4	4.4	0.9	0.9
Minimum–maximum	0.09–14	0.1–7.0	0.09–14	0.2–1.0	0.3–1.5
Endotoxin (EU/m3)
GM (GSD)	444 (4.8)	852 (3.9)ab	348 (3.4)a	107 (5.0)b	146 (7.6)
25th centile	194	395	229	18	48
75th centile	1306	1700	766	428	670
Minimum–maximum	15–10 940	15–10 940	26–2700	17–530	41–5320
Bacteria (×104/m3)
GM (GSD)	17 (5.9)	25 (6.8)a	18 (3.3)b	2 (5.5)abc	30 (2.5)c
25th centile	6.5	13	7	0.3	16
75th centile	55	96	33	10	58
Minimum–maximum	0.3–240	0.3–230	1–240	0.3–15	11–130
Fungal spores (×104/m3)
GM (GSD)	4 (3.3)	4 (3.7)	3 (3.1)	3 (2.9)	3 (2.3)
25th centile	1.4	1.3	1.5	1.3	1.4
75th centile	8	21	4	5.4	6.5
Minimum–maximum	1.0–50	1.1–48	1.1–50	1.3–20	1.0–7.8
β-1,3-Glucans (µg/m3)
GM (GSD)	6 (4.6)	11 (3.9)a	5 (4.1)b	1 (2.5)ab	2 (6.0)
25th centile	2.3	4	2	0.6	0.6
75th centile	19	23	15	3.2	12
Minimum–maximum	0.3–151	0.3–151	0.4–42	0.4–3	0.6–40

GMs with identical letters are significantly different (p≤0.05).

GM, geometric means.