Accumulation of Metals in Soils, Groundwater and Edible Parts of Crops Grown Under Long-Term Irrigation with Sewage Mixed Industrial Effluents

Abstract

Farmers in developing countries irrigate crops using raw urban and industrial effluents with consequent risks from metal contamination. Therefore, soils, crops and groundwater from an effluent irrigation use site were assessed for Cd, Cr, Ni and Pb. Total and available contents of metals in soil followed the order Pb>Ni>Cr>Cd. Crops accumulated more Pb, followed by Cd, Ni and Cr. Pb exceeded the permissible limit with wastewater irrigation only, but Cd exceeded the limit even with combined irrigations of wastewater and groundwater. Among crops, sugar beet assimilated highest Cd (3.14 μg g(-1)) and Pb (6.42 μg g(-1)) concentrations. Legumes accumulated more metals than cereals. Long-term use of wastewater and its conjunctive use with groundwater led to toxic accumulations of Cd, Pb, Ni and Cr. Cd with higher availability and mobility indices and lower toxicity limit, posed the maximum risk of food-chain contamination.

Trace Metal(oid) Accumulation in Edible Crops and Poplar Cuttings Grown on Dredged Sediment Enriched Soil

“…The lack of detectable Pb in most of the plants from our study confirmed the low CaCl 2 -extractible fraction of Pb in substrates from both areas. Yadav et al (2015) found that Pb could be detected in many edible crops ( ; however, their plants were irrigated with contaminated sewage industrial effluents, which could have induced much higher bioavailability (because the authors measured the DTPA [diethylenetriamine pentaacetate]-extractable fraction, a direct comparison with our results is not feasible). Cobalt was only detected in cucumber fruits (on the two substrates) and in pepper leaves, although at much lower levels (on Substrate 1).…”

“…The lack of detectable Pb in most of the plants from our study confirmed the low CaCl 2 –extractible fraction of Pb in substrates from both areas. Yadav et al (2015) found that Pb could be detected in many edible crops (wheat [ Triticum aestivum L.], fenugreek [ Trigonella foenum‐graecum L.], radish [ Raphanus sativus L.], spinach [ Spinacia oleracea L.], bean, clover [ Trifolium L. spp.…”

Effect of Sewage Irrigation on the CT-Measured Soil Pore Characteristics of a Clay Farmland in Northern China

“…Previous studies have shown that sewage irrigation is frequently accompanied by increases in macro- and micro-nutrients and heavy metals in the soil [ 9 , 10 , 11 , 12 ] in addition to changes in soil microbial functional diversity and enzymatic activity [ 13 , 14 , 15 ]. Sewage irrigation can also increase the risk of crop and groundwater pollution [ 16 , 17 ] and reduce soil quality [ 18 ] and the infiltration rate [ 8 , 19 ]. However, the effects of sewage irrigation on soil structure, particularly on pore characteristics, remain unclear.…”

Rationale for the Successful Management of EDTA Chelation Therapy in Human Burden by Toxic Metals

“…Individuals may be exposed to toxic metals present in the environment via multiple routes, such as the respiratory tract through inhalation of air pollution [1], or orally by ingestion of contaminated food and water [2]. Environmental exposure represents a health risk for the general population and more specifically for some professional categories.…”