Distribution of heavy metals in vegetables and soils collected from Bangalore city region: a case study
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Bukkambudi K. Manjunatha
,
Umme Ayman
,
Padmasree Suresh
Abstract
Heavy metal contamination of agricultural products poses a significant threat to public health in rapidly urbanizing regions. This study investigated the concentrations of cadmium (Cd), chromium (Cr), lead (Pb), and nickel (Ni) in agricultural soils and four commonly consumed vegetables (tomato, spinach, carrot, cabbage) from four sites (Hosakote, Nelamangala, Attibele, Malavalli) around Bangalore, India. Samples were digested using nitric acid and analyzed via Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). Results revealed that leafy vegetables, particularly spinach, were the highest accumulators of all metals studied. Notably, Cr concentrations in spinach from Nelamangala reached 44.6 mg/kg, and Pb in spinach from Hosakote was 37.75 mg/kg, values that significantly exceed FAO/WHO safety limits. A poor correlation between soil and vegetable metal concentrations suggests that atmospheric deposition and contaminated irrigation water may be more significant contamination pathways than soil uptake alone. These findings highlight a serious, location-specific health risk associated with vegetable consumption in the Bangalore region and underscore the urgent need for source-specific pollution control and targeted food safety monitoring.
Acknowledgments
Authors would like to thank to the Visvesvaraya Technological University(VTU), Belagavi-590018, Karnataka State, India for the opportunity given to work on this research project.
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Research ethics: Not applicable. Article is original and not submitted anywhere else.
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Informed consent: Informed consent was obtained from all individuals included in this study.
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Author contributions: Authors contributed equally. All authors have accepted responsibility for the entire content of this manuscript and approved its submission.
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Use of Large Language Models, AI and Machine Learning Tools: None declared. English only, not used AI and ML tools etc.
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Conflict of interest: The authors declare no conflict of interest.
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Research funding: No funding from Government organization Self financing for the project work.
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Data availability: Not applicable.
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