Biomonitoring of Selected Heavy Metals Using House Sparrow (Passer Domesticus) Residing in Tehran, Iran

The present study aimed to determine the concentration of heavy metals (lead,
cadmium and nickel) in the external and internal body tissues of house sparrow (Passer domesticus)
living in Tehran, Iran, as a biological monitoring and also to identify possible sources of these
pollutants. One of the challenges of this research was sampling and determining the population of
city sparrows. The concentration of these heavy metals (in mg/kg) was measured in feather, muscle,
blood, adipose tissue and diet samples of birds collected by systematic sampling (n = 96) from
selected parks in the north, south, west and east of the city using inductively coupled plasma optical
emission spectroscopy (ICP-OES) under optimal measurement conditions. Based on the results, the
unwashed feather samples showed the highest concentration for cadmium, as Cd (449.23)> Ni
(4.12)> Pb (3.67), and the washed feather samples indicated that the highest concentration of
cadmium in the northern (456.75) and southern (449.23) regions. The concentration of lead in most
of the regions had relatively similar values, but it was higher in the northern (5.11) and southern
(3.67) regions. The highest concentration of nickel was related to the eastern (29.76) and western
(9.76) regions. The comparison of our results reveals the correlation between the concentration of
heavy metals studied in different tissues of house sparrows and the distribution of polluting sources
in Tehran in terms of traffic load, the establishment of gas stations and industrial pollution transfer
routes.To conclude, house sparrow can be used as a suitable biological indicator in determining the
distribution of changes in the concentration of some heavy metals.