Avaliação das concentrações dos hidrocarbonetos policíclicos aromáticos no material particulado menor que 2,5 um e deposição úmida do Instituto de Aplicação - UERJ.

Abstract

The particulate material below 2,5 micrometer (PM2,5) has its main origin in anthropogenic combustion processes. It can cause various health problems in people, mainly if it is associated with other dangerous substances such as polycyclic aromatic hydrocarbons (PAH). Through wet deposition, the pollutants that are in the PM2,5 are transferred to the rain water. This paper intends to evaluate the concentration of PAH in PM2,5 and in the rain water, which was collected in the Instituto de Aplicação da Universidade do Estado do Rio de Janeiro (Cap-UERJ). For this the sampling of PM2,5 was made with a high volume air sampler and the rain water sampling was made with a catchment and storage system and it used descriptive statistics techniques and three multivariate techniques: correlation coefficient, cluster analysis and principal component analysis (PCA). For the formation of groupings in the analyses of the conglomerates Ward method was utilized. The 16 PAH samples considered priority by EPA, such as Naphthalene (NAF), Acenaphthylene (ACY), Acenaphthene (ACE), Fluorene (FLU), Phenanthrene (PHE), Anthracene (ANT), Fluoranthene (FLT), Pyrene (PYR), Benz(a)anthracene (BaA), Chrysene (CRY), Benzo(b)fluoranthene (BbF), Benzo(k)fluoranthene (BkF) Benzo(a)pyrene (BaP) Dibenz(a,h)anthracene (DBA), Benzo(ghi)perylene (BgP), Indeno(1,2,3-cd)pyrene (IND) were analyzed by the high resolution gas chromatography coupled mass spectrometry detector. The PM2,5 concentration per day it was collected was between 6,46 and 41,16 µg m-3 , with a medium rate of 19,6 µg m-3. This rate does not overtake the numbers allowed by the international legislations, such as EPA and WHO, but if the samples are individually analyzed it is observed 11 violations to the numbers specified by WHO and 4 by EPA. However, PM2,5 only PAH NAF, FLU, PHE, ANT, PYR, FLT, BaA, CRY, BbF, BkF e BaP could be quantified, while in rain water only NAF, PAH with lower molecular mass, and, consequently, of higher solubility in water, could be quantified. The PAH of big molecular mass, between 4 and 5 aromatic rings (PYR, FLT, BaA, CRY and BbF), obtained higher concentrations. The result can be divided into two big groups. The first one is formed by four PAH: ACE, BkF, ANT and FLU. Because it contains lighter PAH, this group is probably linked to emissions originated from heavy vehicles, that is, powered by diesel. The second group is formed by: NAF, BbF, BaA, PYR, FLT, PHE, CRY e BaP. This is possibly related to emissions of light weighted vehicles, due to the 4 or 5 aromatic rings. The correlation coefficient and the PCA obtained present similar results.