Particulate matter (PM10 and PM2.5) from different areas of Puerto Rico

Fine (PM2.5) and coarse (PM10) particles were characterized in different sites of Puerto Rico during 2000 to 2003. The sites were established in urban areas (Guaynabo, Salinas and Vieques) and in a reference site (Fajardo) at the east coast. Particulate matter (PM) samples were collected in Teflon and quartz filters then weighed and processed. PM mass concentrations in Teflon filter were determined gravimetrically and estimated for quartz. Samples were digested for metal analyses with appropriate field blanks. Seven to eight metals (Cd, Co, Cu, Fe, Ni, Pb, V and Zn) plus arsenic (As) were analyzed in each sample by Atomic Absorption Spectroscopy. Average PM10 levels were around 25 mu g m(-3) in all sites being, lower than the limits established by USEPA (50 mu g m(-3)). The annual average level of PM2.5 in Guaynabo was 11.6 mu g m(-3) versus 8.5 mu g m(-3) in Fajardo. Most of the metals were present at higher levels in the urban sites (Guaynabo, Vieques and Salinas) than at the reference site (Fajardo). All species analyzed in PM2.5, except Fe, were significantly higher at Guaynabo when compared to Fajardo. Ni and V exhibited the highest metal concentrations (Ni = 17 ng m(-3) and V = 40 ng m(-3)) in Guaynabo. Fe showed stronaer relationships between PM at each site suggesting their release from similar sources at that particular location, probably due to Sahara dust.