The Distribution between the Dissolved and the Particulate Forms of 49 Metals across the Tigris River, Baghdad, Iraq

Table 1

Toxic metals (min–max) μg/L in Tigris River, with the permissible limits.

		USEPA limits^+		WHO limits^++
Element	(Min–max) μg/L	μg/L		μg/L		WA. μg/L^†
		MCL^a	SDWR^b	DWGV^c	S, N, F, D (W)^d
Aluminum (Al)	347–2,220	—	50–200	100 (LF), 200 (SF)*	—	40
Antimony (Sb)	0.099–0.202	6	—	20	0.1–0.2 S	—
Arsenic (As)	0.99–1.76	10	—	10	1-2 N	1
Barium (Ba)	37.9–61.9	2000	—	700	100 D	—
Boron (B)	75–122	—	—	2400	500 D	30
Cadmium (Cd)	0.016–0.039	5	5	3	1 D	0.001
Chromium (Cr)	1.48–9.03	100	—	50	—	0.1
Copper (Cu)	0.7–12.7	1300	1000	2000	50–30,000 D	1.4
Iron (Fe)	326–2,220	—	300	500–50,000	—	50
Lead (Pb)	0.17–1.36	15	—	10	5 D	0.04
Manganese (Mn)	11.4–61.7	—	50	400	1–200 F	10
Molybdenum (Mo)	2.58–4.56	—	—	70	—	0.8
Nickel (Ni)	2.58–12.7	—	—	70	20 D	0.4
Silver (Ag)	0.002–0.026	—	100	5	50 D**	—
Strontium (Sr)	528–1304	—	—	—	—	100
Thallium (Tl)	0.011–0.026	20	—	—	—	—
Tin (Sn)	0.012–0.181	—	—	0.006–0.01	1-2***	—
Uranium (U)	0.7–1.2	30	—	15	1 D	—
Zinc (Zn)	1.19–7.49	—	5000	10–50	300****	0.2

USEPA limits: ⁺from [22]. WHO limits: ⁺⁺from [23–25]. MCL^a: maximum contaminant level; SDWR^b: secondary drinking water regulations; DWGV^c: drinking water guidelines value; S, N, F, D (W)^d: surface, natural, fresh, drinking water; *(LF): large water treatment facility, (SF): small water treatment facility; **drinking water treated with Ag for disinfection; ***value is exceptional; ****unacceptable. WA^†: world average of trace elements in unpolluted rivers.