Contamination and Dietary Carcinogenesis in various vegetables from local markets in Khairpur, Sindh Pakistan

Abstract

This study evaluates the elemental profiles and associated human health risks of essential macro minerals, trace elements, and heavy metals in commercial vegetables from District Khairpur, Pakistan. Inductively Coupled Plasma Mass Spectrometry (ICP-MS) analysis revealed that potassium overwhelmingly dominates elemental compositions, reaching (200.57 mg/kg) dry weight in potato and averaging (142.78 mg/kg) across all crops drastically exceeding international baseline reference levels without heavy metal co-accumulation. Cabbage exhibited crop-specific hyper-accumulation of calcium (107.95 mg/kg), magnesium (401.5 mg/kg), and sodium (346.0 mg/kg). While essential trace elements (Fe, Cu, Zn, Mn, Co) and non-essential toxic metals (Pb, Cd, Cr, Ni) complied with FAO/WHO Codex Alimentarius safety standards, localized threshold exceedances were identified for arsenic (As). Specifically, tomato samples recorded peak arsenic concentrations of (0.352 mg/kg), significantly breaching the international safety limit of (0.10 mg/kg).USEPA exposure modelling demonstrated a pronounced age-dependent toxicological disparity driven by lower paediatric body weight (15 kg) and higher proportional intake (0.150 kg/day). Estimated Daily Intake (EDI) values in children peaked for nickel (2.30 mg/kg/day) and arsenic (0.77 mg/kg/day). Non-carcinogenic risk analysis revealed that while adult health hazards remained within acceptable boundaries (Hazard Index, HI = 1.04), children faced significant health risks (HI = 3.04), primarily propelled by paediatric arsenic exposure (Target Hazard Quotient, THQ = 2.58). Incremental Lifetime Cancer Risk (CR) metrics confirmed a threefold higher oncogenic burden for children across all evaluated metals, led by nickel (21.48 × 10⁻⁶) and arsenic (11.59 × 10⁻⁶). These findings demonstrate that while Khairpur vegetables serve as high-density macro-nutritional sources, targeted irrigation management and site-specific soil remediation are critical to eliminate paediatric arsenic exposure hazards.