Coliforms and heavy metal contamination in green leafy vegetables

Enumeration of bacteria and coliforms in random samples of palak (Beta vulgaris L), coriander (Coriandrum sativum) and fenugreek or methi (Trigonella foenum-graecum) from agricultural areas in and around Patiala city was conducted to assess level of post harvest contamination. The mean values of total bacterial count in fresh vegetables ranged between 109–250 cfu x 10⁴ g⁻¹ and coliforms 29–87 cfu x 10⁴ g⁻¹. Heavy metals in these vegetables were in the order Fe>Zn>Pb>Cr>Ni>Cd. Only 32% palak, 26% coriander and 23% fenugreek samples contained Pb concentration below the permissible limit of 2.5 mg Kg⁻¹ as per Indian Standard of Food Adulteration Act (PFA), 1954. Among all green leafy vegetables, nearly 67–76% of samples were high in Pb, 18–39% samples were high in Zn, which crossed Indian permissible limit of 50 mg Kg⁻¹ and 6–9% in Cd, which was beyond 1.5 mg Kg⁻¹ as per European Standards.