Heavy Metal Uptake Pattern and Potential Human Health Risk through Consumption of Tomato Grown in Industrial Contaminated Soils

An experiment was conducted in pots to study heavy metal uptake pattern and to assess health risk for adult male and female through consumption of tomato grown in industrial contaminated soils. The experiment was conducted at the net house of the Department of Agricultural Chemistry, Bangladesh Agricultural University, Mymensingh-2202 followed by completely randomized design (CRD) with four replications. Tomato fruits were grown in two types of agricultural soils, one was industrial contaminated and the other was normal farm soil. Edible parts of tomato fruits were harvested at maturity. The amount of Fe, Mn, Cu, Zn, Cr and Pb present in dried fruits, leaves, shoots and roots of tomato were extracted using di-acid mixture and the concentrations of these metals in aqueous extracts were determined by an atomic absorption spectrophotometer (AAS). Health risk was measured by calculating target hazard quotients (THQ) as established by the US EPA. Heavy metals uptake pattern was in the sequence of Cr > Fe > Mn > Cu > Zn = Pb; Fe > Cr > Mn > Cu > Zn > Pb; Fe > Cr > Mn > Zn > Cu > Pb and Cr > Fe > Mn > Zn > Cu > Pb in fruits, leaves, roots and shoots of tomato, respectively. The present study revealed that tomato fruits didn’t accumulate Zn although there was a significant amount of available Zn in the soils. The order of Zn, Cr and Cu accumulation by tomato plants was root ≥ shoot > leaf > fruit. In case of Fe and Mn the sequence were root > leaf > shoot > fruit and leaf > shoot > root > fruit, respectively. Among the metals, available concentration of Cr in soils collected from both sites exceeded the soil quality standards, indicating a high risk to the surrounding ecosystems. The calculated THQ values for the metals showed that only Cr had individual value that surpassed 1, and the values for male were 6.15 & 13.26 and for female were 10.63 & 22.93 due to consumption of tomato grown in farm and industrial contaminated soils, respectively. The overall results showed that industrial contaminated sites were more susceptible than normal agricultural farm sites. The study results inferred that Cr health risk through consumption of tomato is unsafe; and in both places female is more vulnerable than male. Finally, the study recommended to investigate the levels of heavy metals in other vegetables and cereals, and also on the occurrence of the diseases linked to heavy metals in the study area.