Avaliação da contaminação de camarões por HPAs na baía de Guanabara

Abstract

Guanabara Bay is a crucial ecosystem for several species of shrimp and an important source of income for traditional fishermen around the metropolitan region of Rio de Janeiro, however, it has a chronic diagnosis of PAH contamination in its sediment. In this work, the level of contamination of pink shrimp, Farfapennaeus braziliensis and Farfapennaeus paulensis, and gray shrimp, Litopennaeus schmitti, was evaluated by obtaining samples at important fish landing sites (Ilha do Fundão, Ilha do Governador, São Gonçalo and Magé) and a monitoring point in the Central Channel of the GB throughout the months of June to February (outside the closed season). The PAHs levels in the analyzed shrimp tissues were obtained by Sohxlet extraction and determined by gas chromatography associated with mass spectrometry. The results ranged from 1.56 to 87.66 ng.g-1

(w.w) for the ∑ Total PAHs and

from 0.21 to 32.46 ng.g-1

for the ∑ 16 Priority PAHs. There was no significant difference in the concentrations of PAHs determined in the 3 species, however, for the fish landing sites, a significant difference was observed for Gradim, São Gonçalo, pointing to a shrimp capture region that differs from other locations in the inner portion of Guanabara Bay. At the monthly monitoring point carried out in the Central Channel, the results pointed to the months of October, November and December with the highest concentrations of total PAHs, ranging from 23.32 to 48.04 ng.g-1

. In the vast majority of samples, the relative contribution of 2-3 benzene rings was greater than 90%, indicating a preferential contamination of lighter compounds and of petrogenic origin. In general, the results indicate that the level of PAHs in shrimp was not significant and is well below the maximum limit proven by regulatory agencies, national and international, being valuable information for artisanal fishermen who depend on shrimp fishing activity for its survival.