Concentrations of Ni and V, other heavy metals, arsenic, elemental and organic carbon in atmospheric fine particles (PM2.5) from Puerto Rico.

Fine atmospheric particulate PM2.5 (particles with diameters of < 2.5 microm) were sampled in an urban industrialized area--Guaynabo, Puerto Rico (Figure 1)--and in a reference less polluted site Fajardo, Puerto Rico--and analyzed for trace metals, and inorganic and organic elemental carbon. PM2.5 samples were collected from November 2000 to September 2001 using an Andersen Instruments RAAS2.5-400 for periods of 72 h. Metals analyzed were arsenic (As), cadmium (Cd), copper (Cu), iron (Fe), nickel (Ni), lead (Pb), vanadium (V) and zinc (Zn) by atomic absorption. Levels of elemental and organic carbon (EC/OC) were also determined. All metals analyzed, except for Fe, were significantly higher in PM2.5 from Guaynabo when compared to Fajardo. Average levels of PM2.5 in Guaynabo were 11.6 versus 8.5 microg/m3 in Fajardo. Average levels of EC were 1.5 and <0.14 microg/m3; and OC levels were 2.2 and < 1 microg/m3 for Guaynabo and Fajardo, respectively. Levels of Ni (17 ng/m3) and V (40 ng/m3) determined in PM2.5 from the Guaynabo area were high when compared to other cities, and these metals could be responsible for respiratory problems reported in the area. Multivariate analyses showed strong relationships in Guaynabo between Ni and V, PM2.5 and Fe and As and Cu and Pb. In Fajardo, the strongest associations were obtained between PM2.5 and Fe, Cd and V and Ni and Pb and Cu, these last three elements exhibiting an inverse relationship.