Influence of groundwater and wastewater irrigation on lead accumulation in soil and vegetables: Implications for health risk assessment and phytoremediation

Abstract

The current study evaluated the effect of groundwater and wastewater irrigation on lead (Pb) accumulation in soil and vegetables, and its associated health implications. A pot experiment was conducted in which spinach (Spinacia oleracea), radish (Raphanus sativus), and cauliflower (Brassica oleracea) were irrigated with groundwater and wastewaters containing varying concentrations of Pb. Lead contents were measured in wastewaters, soils and root and shoot of vegetables. We also measured health risk index (HRI) associated with the use of vegetables irrigated by wastewaters. Results revealed that Pb contents in groundwater and wastewater samples (range: 0.18-0.31 mg/L) were below the permissible limits (0.5 mg/L) set by the Food and Agriculture Organization (FAO). Application of Pb-containing groundwater and wastewater increased Pb concentration in soil and vegetables. Lead concentrations in all soils ranged from 10 to 31 mg/kg and were below the permissible limits of 300 mg/kg set by the European Union. Significant Pb enrichment was observed in the soils whereby all types of vegetables were grown and assessed for Pb risk. Our data showed that Pb contents, in all three vegetables (21-28 mg/kg DW), were higher than the permissible Pb limit of FAO (5 mg/kg Dry Weight (DW)). The HRI values were > 1.0 for radish and cauliflower. It is proposed that Vehari city wastewater/groundwater must be treated prior to its use for irrigation to avoid vegetable contamination by Pb, and as such for reducing Pb-induced human health risk.

Arsenic Uptake, Toxicity, Detoxification, and Speciation in Plants: Physiological, Biochemical, and Molecular Aspects

“…Soil pH is considered a master/key variable governing the chemical speciation of metals in soil [ 98 , 99 , 100 ]. It has been reported that the biogeochemical behavior of As in the soil–plant system mainly depends on soil pH [ 2 ].…”

A Review of Environmental Contamination and Health Risk Assessment of Wastewater Use for Crop Irrigation with a Focus on Low and High-Income Countries

“…In the areas where fresh water is in short supply, wastewater is frequently used for crop irrigation. Although not legally permitted in most countries, the use of untreated wastewater for crop irrigation has been practiced in many countries worldwide due to the shortage of good quality water [ 2 , 3 , 4 ].…”

Citric Acid Assisted Phytoremediation of Chromium through Sunflower Plants Irrigated with Tannery Wastewater

“…Tannery wastewater contains several organic and inorganic pollutants [2]. Farmers mostly use tannery wastewater in periurban areas due to a scarcity of irrigation water [3,4]. There are different heavy metals in tannery wastewater, such as Cr, Cd, Mn, Pb, Fe, Ni, and Cu.…”