Table 10a.

Association between formaldehyde and other unspecified leukemia (ICD-8 207).

	Beane Freeman et al., 2009
	NCI Cohort (1934-2004)
Measures	Category	Obs	Estimate		95% CI
Peak Exposure	0 ppm	2	RR	0.61	0.13–2.85
	>0–<2.0 ppm	13	RR	1.00	—
	2.0–<4.0 ppm	8	RR	0.86	0.35–2.12
	≥4.0 ppm	13	RR	1.15	0.53.2.53
	ptrend > .5 (exposed)
	ptrend = .5 (exposed and unexposed)
Average Intensity	0 ppm	2	RR	0.58	0.13–2.62
	>0–<0.5 ppm	21	RR	1.00	—
	0.5–<1.0 ppm	7	RR	0.98	0.42–2.33
	≥1.0 ppm	6	RR	0.84	0.33.2.12
	ptrend > .5 (exposed)
	ptrend > .5 (exposed and unexposed)
Cumulative Exposure	0 ppm-yr	2	RR	0.77	0.16–3.59
	>0–<1.5 ppm-yr	15	RR	1.00	—
	>1.5–<5.5 ppm-yr	10	RR	1.65	0.73–3.73
	≥5.5 ppm-yr	9	RR	1.44	0.61.3.36
	ptrend = .15 (exposed)
	ptrend = .13 (exposed and unexposed)
Cumulative number of peaks .4.0 ppm	No association. Results not shown.
Duration of Employment	No association. Results not shown.