Table 3.

Urine concentration of arsenic, cadmium and lead for CKDu cases compared with controls from the endemic and non-endemic areas

	Mean, median (range) of concentration in urine (μg/g creatinine)
	Arsenic	Cadmium	Lead
CKDu cases (n = 495)	45.447, 26.3 (0.4 to 616.6)	1.039, 0.695 (0.005 to 8.93)	1.153, 0.95 (0.04 to 8.53)
Controls from endemic area (n = 132)	92.443, 6.99 (0.2 to 966.29)	0.646, 0.18, (0.005 to 5.13)a	1.254, 0.793 (1.21 to 6.64)
Controls from non-endemic area (n = 250)	56.572, 42.025 (5.38 to 350.28)	0.345, 0.265 (0.005 to 2.079)b	2.099, 1.434 (0.277 to 20.9)

^a Urine cadmium concentration of cases compared to controls from endemic area P < 0.001.

^b Urine cadmium concentration of cases compared to controls from non-endemic area P < 0.05.