Background: Exposure to heavy metals (Pb and Cd) through diet posses a significant risk to human health. Areas of Mlolongo, Athi River and Syokimau are surrounded by industries, which dispose off their waste water to existing rivers and streams. The waste water is further used for irrigation which increases consumption of vegetables contaminated with lead and cadmium by human populations. Sample collection and analysis: samples were collected from markets, supermarkets and open air markets in Mlolongo, Athi river and Syokimau areas. Samples were analyzed for Lead and Cadmium using the AAS method as outlined in the AOAC. Results: Kale from farms around Mlolongo had lead content of 41.10±3.15µg/Kg compared to kale from farms in Syokimau (0.36±0.01µg/Kg). Spinach had lower concentration of lead (14.10±1.05µg/Kg) in farms in Mlolongo and 1.70±0.06µg/Kg in supermarkets in Syokimau. Than spinach. To the contrary cadmium contents were higher in spinach (0.51±0.02µg/Kg in supermarket in Mlolongo) than kale (0.38±0.01µg/Kg supermarkets in Mlolongo and Syokimau). Kale had a higher lead than cadmium content in the firm one in Athi river (14.00±2.10µg/Kg) than 3.80±0.81 µg/Kg) in the second farm which was the lowest. Vegetables from farm one are irrigated using effluent water from close industries. Lead content was highest in the first market (14.00±2.10µg/Kg) than the second market (3.80±0.81µg/Kg) in Athi river town. Cadmium contents were lower than lead but highest in the third market than the second market in the same town (0.20±0.07µg/Kg). Cadmium content was high in kale from supermarket in Athi river at (3.70±0.07 µg/Kg). Concentrations of lead in spinach were highest in the first farm at 5.30±1.10 µg/Kg and least in the spinach in supermarket at 0.30±0.01 µg/Kg. Conclusions: Lead content in vegetables vended in Athi river, Syokima and Mlolongo were above those recommended by the Ministry of Health and WHO. Similarly, cadmium content were high but within normal requirements. Exposure of lead to human populations, especially children is harmful to neurological developments.

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