VATIS UPDATE Article

A team of researchers from the Islamic Azad University (IAUPS) and Tehran University of Medical Sciences, Islamic Republic of Iran, have determined the accumulation of heavy metals in Plarganium grandiflorum grown in chemical and toxicology laboratories’ pharmaceutical effluent and wastewater irrigated soil in the vicinity of sewage treatment plant (STP), Tehran. The results revealed that wastewater was highly rich in plant nutrients and heavy metals. The wastewater irrigation significantly (P<0.05/P<0.01) increased the contents of heavy metals in the soil and plants grown in wastewater irrigated soil.

The enrichment of various metals were recorded in the order of Fe >Zn > Pb >Cu > Cd > Cr > Mn in these plants. Moreover contents of different heavy metals in the different parts of plants such as root and stems showed significant (P<0.05) and positive correlation with contents of Cd (r = +82 to r = +96), Cr (r = +74 to r = +94), Cu (r = +84 to r = +98), Fe (r = +88 to r = +98), Mn (r = +80 to r = +96), Pb (r = +74 to r = +96) and Zn (r = +88 to r = +98) in the wastewater irrigated soil. Although, the contents of Cd, Cu, Fe, Mn, Pb and Zn in soil after growing of Plarganium grandiflorum after 60 days were recorded within the prescribed limit of WHO/FAO standards.

Pelargonium (Grandiflorum) has shown ability to extract lead, Cr (III), Cr (VI) and Cd from contaminated soils; about 35.9%, 41.9%, 41.7% and 29.8% respectively in the root and leaves zone. To quantify the occurrence and the distribution of heavy metals and to prevent them from passing through wastewater collection and treatment systems into soil and ground water bodies represents an urgent task for applied environmental sciences in the coming years. The responsible organizations should stimulate research to upgrade existing waste water treatment by implementing phytoremediation modules and demonstrating their reliability to the public.