Table 2.

Comparisons of mean concentrations (mg Kg⁻¹) ± S.D of selected heavy metals in soil of some vegetable fields treated four different irrigation systems.

		GWI	RWI	Dom.WWI	Dr.WWI
Fields of vegetables	HMs	Means ± SDs	Means ± SDs	Means ± SDs	Means ± SDs
Phaseolus vulgaris (Green bean)	As	4.86 ± 0.17	5.58 ± 0.46	6.78 ± 0.06	14.73 ± 0.21
	Cd	3.29 ± 0.24	3.61 ± 0.03	5.10 ± 0.88	8.61 ± 0.07
	Pb	3.56 ± 0.11	4.78 ± 0.12	4.78 ± 0.12	12.58 ± 0.16
Spinacia oleracea (Spinach)	As	6.39 ± 0.21	9,21 ± 1.59	10.12 ± 0.01	13.82 ± 0.58
	Cd	1.33 ± 0.05	3.06 ± 0.02	3.24 ± 0.33	3.81 ± 0.04
	Pb	4.35 ± 0.02	7.84 ± 0.05	9.60 ± 0.07	10.32 ± 0.29
Brassica compestris (Mustard)	As	3.17 ± 0.43	3.87 ± 0.05	14.38 ± 2.57	12.55 ± 0.17
	Cd	3.46 ± 0.21	3.44 ± 0.33	5.44 ± 0.33	8.56 ± 0.28
	Pb	4.23 ± 0.11	6.66 ± 0.17	10.33 ± 0.26	13.36 ± 0.40
Raphanus sativus (Radish)	As	3.34 ± 0.51	5.86 ± 0.11	17.51 ± 3.09	19.19 ± 0.27
	Cd	3.36 ± 0.03	2.57 ± 0.05	5.57 ± 0.04	9.11 ± 0.03
	Pb	4.30 ± 0.10	6.10 ± 0.44	11.90 ± 0.99	12.58 ± 0.23
Daucus carota (Carrot)	As	2.69 ± 0.61	4.91 ± 0.07	6.41 ± 0.16	14.26 ± 0.04
	Cd	2.53 ± 0.02	3.99 ± 0.02	3.99 ± 0.02	7.32 ± 0.06
	Pb	2.41 ± 0.03	3.75 ± 0.08	10.89 ± 0.07	15.45 ± 0.11
Solanum tubersom (Potato)	As	2.36 ± 0.10	4.19 ± 0.15	10.48 ± 0.08	114.28 ± 0.12
	Cd	1.27 ± 0.12	3.85 ± 0.06	3.57 ± 0.19	2.61 ± 0.35
	Pb	3.22 ± 0.01	5.09 ± 0.01	11.88 ± 0.33	10.40 ± 0.01

Permissible limit of standard os India, 2000, Ashwathi (As = NA, Cd = 3–6 mg Kg⁻¹, Pb = 250–500 mg Kg⁻¹).

Permissible limit of EU, 2006 (European Commission, 2006;Joint FAO/WHO Expert Committee on Food Additives, 2014) (As = NA, Cd = 5 mg Kg⁻¹, Pb = 100 mg Kg⁻¹).

Permissible limit of FAO/WHO 2001 (As = 20 mg Kg⁻¹, Cd = 0.3 mg Kg⁻¹, Pb = 100 mg Kg⁻¹).