Table II.

Dose-dependent monosomy and trisomy rates of the 22 autosomes among groups exposed to no, <10 p.p.m. and ≥10 p.p.m. benzene^a

Chromosome	Monosomy			Chromosome	Trisomy
	IRRb	95% CIc	P-value		IRRb	95% CIc	P-value
7	1.51	1.18–1.92	0.001	6	1.79	1.21–2.65	0.003
5	1.50	1.18–1.91	0.001	21	1.68	1.37–2.05	4.170E-07
10	1.43	1.12–1.83	0.005	14	1.57	1.20–2.06	0.001
19	1.34	1.07–1.67	0.01	5	1.57	1.15–2.13	0.004
6	1.32	1.07–1.64	0.01	10	1.51	1.16–1.98	0.003
16	1.29	1.05–1.58	0.02	16	1.49	1.05–2.12	0.03
1	1.23	0.98–1.55	0.07	7	1.48	1.05–2.08	0.02
12	1.19	0.96–1.47	0.11	8	1.37	1.09–1.72	0.007
13	1.18	0.92–1.52	0.20	22	1.35	1.01–1.80	0.04
14	1.15	0.93–1.43	0.20	12	1.34	1.00–1.79	0.05
20	1.15	0.91–1.44	0.24	11	1.28	0.97–1.70	0.08
17	1.13	0.95–1.35	0.16	9	1.28	1.00–1.62	0.05
18	1.13	0.93–1.37	0.21	4	1.27	0.98–1.64	0.08
21	1.13	0.91–1.40	0.26	1	1.26	0.99–1.60	0.06
8	1.13	0.90–1.41	0.31	13	1.24	0.86–1.79	0.25
15	1.12	0.94–1.34	0.20	19	1.23	0.96–1.56	0.10
3	1.10	0.93–1.32	0.27	17	1.22	0.93–1.60	0.16
4	1.10	0.90–1.35	0.35	18	1.18	0.89–1.58	0.25
9	1.07	0.90–1.27	0.46	20	1.14	0.86–1.52	0.36
22	1.06	0.88–1.26	0.55	3	1.05	0.81–1.37	0.71
11	1.04	0.85–1.26	0.71	2	1.03	0.71–1.48	0.89
2	0.85	0.65–1.10	0.21	15	1.02	0.77–1.35	0.90

^aData listed according to IRR values.

^bIRR, adjusted for age, sex, alcohol, infection status and smoking and for a 20 U increase in exposure.

^c95% confidence interval.