. 2014 Jul 18;11(7):7319–7332. doi: 10.3390/ijerph110707319

Table 2.

Differences of urinary arsenic species and methylation indices between subgroups.

Variables	n	iAs (μg/g Cr) ^a	MMA (μg/g Cr) ^a	DMA (μg/g Cr) ^a	tAs (μg/g Cr) ^a	iAs% ^a	MMA% ^a	DMA% ^a	PMI ^a	SMI ^a
Sex
Male	120	98.4 ± 80.8	80.6 ± 58.1	266.2 ± 191.7	445.2 ± 277.1	25.5 ± 15.5	16.8 ± 7.6	57.7 ± 14.0	0.75 ± 0.15	0.78 ± 0.11
Female	182	114.9 ± 166.4	87.0 ± 69.4	356.8 ± 250.3	558.7 ± 403.2	22.5 ± 15.4	14.6 ± 5.8	63.0 ± 13.1	0.78 ± 0.15	0.81 ± 0.07
p-value		0.425	0.578	0.006	0.029	0.042	0.183	0.039	0.455	0.039
Age (years) ^b
≤51	155	118.8 ± 180.8	72.4 ± 62.5	277.5 ± 210.8	468.7 ± 376.5	27.2 ± 17.7	14.3 ± 6.6	58.5 ± 14.5	0.73 ± 0.18	0.81 ± 0.08
>51	147	97.3 ± 71.3	97.2 ± 65.7	366.5 ± 246.4	560.9 ± 341.5	19.9 ± 11.7	16.7 ± 6.5	63.5 ± 12.3	0.80 ± 0.12	0.79 ± 0.10
p-value		0.657	<0.001	0.003	0.010	<0.001	0.001	0.054	<0.001	0.145
BMI (kg/m²)
≤25	213	105.1 ± 86.2	86.1 ± 65.4	312.2 ± 210.6	503.4 ± 312.6	23.6 ± 14.9	16.0 ± 6.8	60.5 ± 13.3	0.76 ± 0.15	0.79 ± 0.09
>25	89	116.1 ± 219.2	80.4 ± 64.7	341.5 ± 278.9	538.0 ± 461.1	23.8 ± 16.9	14.3 ± 6.3	61.9 ± 14.5	0.76 ± 0.17	0.82 ± 0.07
p-value		0.144	0.199	0.748	0.451	0.323	0.125	0.415	0.980	0.171
Smoking
Current or former	107	96.5 ± 76.1	85.3 ± 64.4	296.8 ± 200.5	478.6 ± 295.3	23.0 ± 14.7	16.3 ± 6.6	60.7 ± 12.8	0.77 ± 0.15	0.79 ± 0.08
Never	195	114.8 ± 163.3	84.0 ± 65.7	334.0 ± 248.2	532.7 ± 393.6	24.0 ± 15.9	15.0 ± 6.7	61.0 ± 14.2	0.76 ± 0.16	0.80 ± 0.09
p-value		0.466	0.742	0.777	0.575	0.823	0.253	0.671	0.573	0.957
Drinking
Current or former	68	105.0 ± 88.0	78.7 ± 65.3	258.7 ± 177.6	442.4 ± 274.0	27.8 ± 17.8	15.9 ± 7.0	56.3 ± 14.6	0.72 ± 0.18	0.78 ± 0.08
Never	234	109.3 ± 150.7	86.1 ± 65.1	338.9 ± 243.9	534.3 ± 382.1	22.5 ± 14.6	15.3 ± 6.6	62.2 ± 13.1	0.78 ± 0.15	0.80 ± 0.09
p-value		0.475	0.500	0.102	0.255	0.008	0.968	0.112	0.082	0.755

^a Values are mean ± SD; ^b Cut point is median value of this variable.