Agrotechnologie

Abstrait

Heavy Metals Levels and Adult Health Risk Assessment in Horticultural Systems in Mbare Musika and Mutoko, Zimbabwe

Samuel Kodani*, Elias Chipunza, Stanislaus Zvarimwa

Levels of cadmium, chromium, cobalt, nickel and lead were determined in cabbages, tsunga (mustard), green beans and tomatoes from Mbare Musika vegetable market in Harare and one of its major supplier, Mutoko. Cabbages and tsunga exceeded the stipulated safe limit for lead levels whereas the tomatoes and sugar beans went above the 0.02 ppm threshold for cadmium. Hazard Quotients of the vegetables showed adult health consequences especially on lead and cadmium and also Hazard Indices were all above unit according to ATSDR (Agency for Toxic Substances and Disease Registry). Horticultural inputs assessment showed that irrigation water exceeded WHO stipulated thresholds for cadmium and chromium. Chromium and lead levels were high in fertilizers indicating most heavy metals within the horticultural system in Mutoko are of anthropogenic origin. There is need for an intervention in regulating heavy metals levels in the agricultural inputs.