Table 2.

Hazard ratios for total cancer incidence by quartile of arsenic and inorganic arsenic intake

	Intake by quartile				p trend
	Lowest	Second	Third	Highest
Arsenic
Men
Median intake (μg/day)	88.8	127.8	166.1	247.5
Number of cases	1,002	1,038	1,116	1,167
Person-years of follow-up	112,502	112,696	112,003	109,158
Age–area-adjusted HR (95 % CI)	1.00	1.00 (0.92–1.09)	0.99 (0.91–1.08)	0.98 (0.89–1.06)	0.56
Multivariate HR (95 % CI)	1.00	1.01 (0.92–1.11)	1.04 (0.94–1.14)	1.03 (0.94–1.13)	0.50
Women
Median intake (μg/day)	93.7	132.2	171.5	25.3
Number of cases	635	646	715	683
Person-years of follow-up	133,894	135,104	134,924	132,963
Age–area-adjusted HR (95 % CI)	1.00	0.99 (0.89–1.10)	1.05 (0.95–1.18)	0.98 (0.88–1.10)	0.96
Multivariate HR (95 % CI)	1.00	0.99 (0.88–1.12)	1.07 (0.96–1.21)	0.98 (0.87–1.10)	0.94
Inorganic arsenic
Men
Median intake (μg/day)	36.5	51.4	64.7	102.2
Number of cases	1,084	1,072	1,042	1,125
Person-years of follow-up	111,399	112,541	112,403	110,017
Age–area-adjusted HR (95 % CI)	1.00	0.96 (0.88–1.05)	0.91 (0.83–0.99)	0.94 (0.86–1.02)	0.09
Multivariate HR (95 % CI)	1.00	0.98 (0.89–1.07)	0.95 (0.87–1.05)	1.00 (0.91–1.10)	0.92
Women
Median intake (μg/day)	37.1	51.2	64.1	107.6
Number of cases	634	649	722	674
Person-years of follow-up	134,833	134,486	134,491	133,075
Age–area-adjusted HR (95 % CI)	1.00	1.02 (0.91–1.14)	1.10 (0.99–1.23)	1.02 (0.91–1.14)	0.51
Multivariate HR (95 % CI)	1.00	1.00 (0.89–1.12)	1.08 (0.96–1.22)	0.99 (0.87–1.11)	0.85

Multivariate HRs were adjusted for age, area, body mass index, smoking status, frequency of alcohol intake, and leisure time physical activity. They were further adjusted for menopausal status and use of exogenous female hormones in women