Assessment of heavy metals in Ipomoea aquatica Forssk. and potential effects on human health

In wetlands areas, macrophytes indicate the extent of bioavailable heavy metal contamination, and particular species of aquatic vascular plants are employed to evaluate the bioavailable fraction of heavy metal pollution. However, heavy metal bioavailability and absorption by aquatic plants depend on various environmental factors. This study aims to determine the presence of heavy metals such as lithium (Li), chromium (Cr), and nickel (Ni) in Ipomoea aquatica Forssk collected from the Lamphelpat wetland in Imphal West District of Manipur, India. It also focused on assessing the associated health risk with prolonged consumption of I. aquatica referring to the Estimated Daily Intake (EDI) of the concerned heavy metals, the Target Hazard Quotient (THQ), and the Hazard Index (HI). A total of 24 composite samples were collected across the three seasons in 2022-2023 and analyzed them for the heavy metals using ICP-MS. The results showed that concentrations (mean±SD) of nickel (4.032±0.830) and chromium (3.448±1.267) in the collected samples were higher than the permissible limit of 1mg/kg set by the FSSAI for leafy vegetables. Concentration of studied heavy metal in I. aquatica were in the order of Ni > Cr > Li. According to THQs and HI, consumption of the examined species is considered unsafe for human health, as the THQ value of Cr is >1. The overall HI for both men and women is also >1. The gender-wise estimation of THQs indicates a greater impact on the women population compared to the male.