Abstract:
Background: Heavy metal pollution is a menace to our environment as they are foremost
contaminating agents of our food supply, especially vegetables. This is great concern to the
public health, agricultural production, and environmental health.
Objective: to assess human health risk for consumption of vegetable cultivated by
fertigation of municipal solid waste compost with natural soil in Jimma town, Ethiopia.
Methods: The study was conducted in Jimma town 2019 by using cross sectional study
design. The samples were collected during dry season for heavy metal analysis from two
sites (Abdi Jimma and Aba Milki sites). Heavy metal concentration was analyzed by atomic
absorption spectrophotometer. Health risks associated with these heavy metals (As, Cd, Cr,
Pb, Cu and Zn) from consumption of vegetable (tomato, beetroot, lettuce, onion and
spinach) were assessed based on total hazard quotients:
Findings: The concentration of heavy metals in edible parts of vegetables increase in
vegetables grown in Abdi Jimma when compared with Aba Milki farm site metal
concentration for Zn, Pb, Cu, and As. The mean metal concentrations in vegetable for
As(0.72) and Zn(65.48) was above the safe limits of World Health Organization’s standards,
while the mean Cd(0.0745), Cr(0.36), Pb(0.176) and Cu(3.33) concentration were below
safe limit. Health risk for As, Cd, Cr, Pb, Cu and Zn, possess nearly free of risk to the local
in habitants through consumption of contaminated vegetable grown in the area as the value
for total hazard quotient was less than 1, but the long term accumulation of these metal
gradually increase the concentration in the environment and accumulates in the body and
can cause serious health problems.
Conclusions: Natural compost preparation from waste materials requires detail
characterization and selecting waste items with low concentration of heavy metals. Regular
monitoring of heavy metals is essential to prevent excessive build up in the food chain and
prevent serious health risk of population.
Recommendation: the composition of organic fertilizer and the soils from which vegetable
crops can grow should be monitored and regulated.
