Genotoxic effects after in vivo exposure of vegetable extracts containing heavy metals from the Dhapa area of Calcutta, India. I. Effects of cauliflower, spinach and radish

Unveiling the threat of lead, cadmium, and nickel toxicity in salient commercially grown vegetables in Kolkata, India

Heavy metal (HM) contamination in agricultural crops, particularly vegetables, is a matter of global concern due to its potential health risks to humans. Commercially growing vegetable samples were analyzed for heavy metals using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) for leafy greens and fruit vegetables collected during winter from highly susceptible zones, in the vicinity of Kolkata. ICP-MS is advantageous over Atomic Absorption Spectrometry (AAS) for unparalleled accuracy, efficiency, faster turnaround time, cost-effectiveness, etc. The results revealed that Saturia (Pb, 0.1-0.3 mg/Kg; Cd, 0.1 mg//kg; Ni, 0.1-0.2 mg/Kg) and Dhapa (Pb, 0.2-1.3 mg/Kg; Cd, 0.07-0.2 mg/Kg; Ni, 0.1-0.3 mg/Kg) have shown significantly higher heavy metal accumulation in the edible part of the vegetables. Leafy vegetables such as red spinach, bathua, and coriander have shown much higher accumulation (Pb, 0.1-1.3 mg/Kg; Cd, 0.07-0.2 mg/Kg; Ni, 0.1-0.2) than fruit vegetables in the edible parts, except capsicum from Chelegualia (Pb, 0.11 mg/Kg; Cd, 0.135 mg/Kg; 0.18 mg/Kg). Translocation factor (< 1.5) and bioaccumulation factor (< 1.2) are observed to have lower values for Dhapa, Saturia, Jirangachi, Raghunathpur, and Kulti compared to Chelegualia, Gabtala, and Vogalirampur. The health-risk effect Hazard Index is greatest in Dhapa, Saturia, and Chelegualia regions. Pb in red spinach and mustard in Dhapa had a higher hazard quotient. The study highlights the need for monitoring the regulation of HM contamination in commercially growing belts near Kolkata to ensure food safety and protection of human health. Putative remedial strategies like phytoremediation involving hyperaccumulators, soil amendments like biochar, and microbial mechanisms for diminishing the translocation of HMs to edible commodities are being explored presently.

Detection of micronucleus and abnormal nucleus in erythrocytes from the gill and kidney of Labeo bata cultivated in sewage-fed fish farms

Determination of genotoxic effect in fish, micronucleus test as well as the study of the abnormal shape of nuclei is a suitable measure, in which the presence or absence of genotoxins can be detected in water. In the present study, micronuclei and abnormal nuclei frequencies were scored in the gill and kidney erythrocytes of the fish Labeo bata grown in the sewage-fed fish farms of East Calcutta wetlands. Three experimental sites were chosen, namely, Bantala, Chowbaga and Chingrihata (basically these sites have sewage-fed fishponds), which were compared with fishponds of no sewage influence as the control area. Highly significant differences (P<0.001) were noticed for micronucleus frequencies in the gill and kidney erythrocytes of experimental fishes, where kidney erythrocytes showed an increased value than gill erythrocytes without any statistical differences. The frequencies of nuclear abnormalities such as necrotic cells, apoptotic cells, notch nucleated cells and binucleated cells were also counted separately for gill and kidney erythrocytes, in which significantly (P<0.001, P<0.01, P<0.05) increased values were obtained in comparison to control populations. These genotoxicity results confirmed that the sewage-fed ponds contain genotoxic metals such as Cr, Zn, Cu, Pb, Mn, Fe through wastewater and sludge because of the direct use of sewage water without pretreatment which may lead to health risks among humans through chronic consumption of fish from these experimental fish ponds. Other vertebrates grown in sewage-fed ponds may also suffer a certain amount of genotoxic substances.