Table 1.

Arsenic biomarkers by demographic characteristics at baseline

	Total Arsenic (g/L)				Inorganic and Methylated Arsenic (µg/L)				Arsenobetaine (µg/L)
Percentile	25	50	75		25	50	75		25	50	75	Total (N)
Sex
Female	5.61	9.21	16.11		1.29	1.84	2.38		0.30	0.49	1.08	1175
Male	5.72	9.74	15.97		1.37	1.88	2.44		0.33	0.51	1.08	735
Age
<18	6.41	10.12	17.15		1.50	2.03	2.58		0.34	0.46	0.71	225
18–35	6.23	10.15	17.65		1.49	1.97	2.46		0.32	0.51	1.03	741
35–50	5.30	9.07	15.41		1.22	1.78	2.37		0.29	0.51	1.23	596
>50	4.64	7.95	13.41		1.09	1.65	2.16		0.30	0.49	1.44	348
Region
Arizona	8.51	14.06	24.38		1.83	2.33	2.80		0.31	0.51	1.17	511
Oklahoma	4.99	7.76	12.17		1.20	1.65	2.10		0.33	0.52	1.07	713
North and South Dakota	5.19	8.39	14.79		1.22	1.78	2.30		0.29	0.46	0.98	686
Education
Less than high school	6.67	12.36	24.29		1.53	2.27	2.81		0.32	0.50	1.08	114
Some high school	6.35	10.34	18.42		1.46	2.01	2.60		0.32	0.47	0.83	547
High school diploma	5.73	8.68	14.85		1.35	1.81	2.32		0.29	0.49	0.96	674
Some college	5.11	8.58	13.79		1.18	1.74	2.23		0.33	0.55	1.36	575
Smoking status
Never	5.88	9.42	16.06		1.37	1.88	2.39		0.32	0.51	1.14	825
Forsmer	5.49	8.31	14.51		1.21	1.71	2.27		0.33	0.54	1.22	393
Current	5.59	9.94	16.99		1.37	1.91	2.47		0.29	0.46	0.98	692
Alcohol
Never	6.27	9.58	15.52		1.29	1.89	2.41		0.31	0.50	0.85	205
Former	5.41	8.71	14.40		1.26	1.80	2.28		0.30	0.48	1.11	489
Current	5.80	9.63	17.23		1.37	1.89	2.45		0.32	0.51	1.07	1216
Diabetes status
Yes	5.82	10.31	13.94		1.39	1.97	2.25		0.28	0.45	1.17	78
No	5.70	9.31	16.09		1.34	1.86	2.40		0.31	0.50	1.07	1832
Body Mass Index
<25	5.11	8.36	14.45		1.19	1.75	2.29		0.30	0.47	0.77	390
25–<30	5.61	9.18	15.58		1.29	1.80	2.36		0.32	0.52	1.16	514
≥30	6.03	9.89	17.80		1.39	1.93	2.48		0.31	0.51	1.22	1006