Suspended particulate and heavy metal

in Cairo Air

Nasralla*, M.M. and Ali, E.A.

(Air Pollution Depart., National Research Center, Dokki, Cairo, Egypt)

ABSTRACT

Were at three locations in Cairo, Egypt during 1997. Particulate concentrations have been measured in three ranges; total suspended particulate (TSP), thoracic particulate (PM10) and fine particulate (PM2.5). Heavy metals, namely lead, chromium, Cadmium, vanadium, manganese, nickel, zinc, iron and copper were analyzed in each of particulate size fraction. The annual mean suspended particulate in the examined areas ranged between 375 ug/m^3 to 625 ug/m^3 PM10 found to constitute 33% 45% of total suspended particulate in Cairo. PM10 ranges between 120 to 560 ug/m^3 (average over 24h) compared to 70 ug/m^3 the Egyptian air quality standard for 24h. The PM2.5 averaged 45% of PM10 at city center and 35°% in the suburban area. More than 75% of heavy metals (Pb, Cd, Ni, Cr, V) in Cairo air were found in the PM10 fraction. Moreover, the average ratio between nickel concentrations in PM,),; to that found in PM1o at city center was about 3 and that ratio for lead was more than four. On the other hand iron was found similarly distributed in both fine and coarse fractions of dust. It was concluded that health of people living in Cairo are at high risk because of the inhalation of most of toxic heavy metals in the fine particles penetrating the alveolar region. Other conclusions and recommendations are included.

* To whom atiy correspondence should be addressed