Risk Assessment of Trace Element Contamination in Drinking Water and Agricultural Soil: A Study in Selected Chronic Kidney Disease of Unknown Etiology (CKDu) Endemic Areas in Sri Lanka

Table 3

Statistical evaluation of concentrations of selected toxic metals/metalloids of the drinking water sources in the selected areas: Eppawala (EP) and Ambagaswewa (AM) GNDs and the reference (RE).

Metal element	Sample	Mean	±SE mean	Minimum	Median	Maximum
Cr (μg/L)	EP	0.27	0.03	0.02	0.13	0.66
	AM	0.26	0.05	0.01	0.13	1.13
	RE	0.22	0.03	0.05	0.25	0.65
Mn (μg/L)	EP	157	25.6	0.30	25.0	485
	AM	62.0	9.46	0.10	19.5	163
	RE	129	19.5	0.20	189	122
Fe (μg/L)	EP	135	38.9	0.00	89.5	867
	AM	60.6	13.7	0.40	16.2	305
	RE	260	41.3	0.60	189	299
Cu (μg/L)	EP	1.37	0.16	0.49	0.96	4.59
	AM	0.67	0.05	0.21	0.65	1.25
	RE	0.98	0.09	ND	0.88	2.88
As (μg/L)	EP	0.25	0.30	0.03	0.19	0.68
	AM	0.19	0.02	ND	0.15	0.57
	RE	0.55	0.08	0.05	0.72	2.29
Cd (μg/L)	EP	0.07	0.00	ND	0.06	0.07
	AM	0.02	0.00	ND	0.01	0.13
	RE	0.01	0.02	ND	0.34	0.45
Pb (μg/L)	EP	0.32	0.07	ND	ND	1.78
	AM	0.20	0.02	0.05	0.14	0.66
	RE	0.15	0.16	0.07	0.21	0.48
Zn (μg/)	EP	40.0	10.3	2.60	18.3	289
	AM	12.0	1.73	1.32	6.53	38.9
	RE	30.7	8.16	0.91	6.58	106

ND: not detected.