No presente estudo, foram utilizados parâmetros hematológicos do peixe tropical estuarino Centropomus parallelus como biomarcador não destrutivo. Os peixes foram coletados, no verão e no inverno, em dois estuários: Cananéia (CAN) e São Vicente (SVE). Foram analisados: hematócrito (Ht), contagem de eritrócitos (RBC), volume corpuscular médio (VCM), leucograma (WBC) e trombograma. Os peixes de ambos locais apresentaram variações no quadro hematológico devido à sazonalidade e aos níveis de degradação ambiental. Os peixes de Cananéia apresentaram aumento no número absoluto de trombócitos no verão, enquanto aqueles coletados em São Vicente apresentaram hematócrito (Ht) e Volume Corpuscular Médio (MCV) menor no inverno. Comparando o quadro hematológico dos peixes dos dois estuários, observamos maiores valores de hematócrito (Ht), Volume Corpuscular Médio (MCV), leucócitos (WBC), e número de eritrócitos (RBC) nos peixes de São Vicente no verão, enquanto no inverno, Ht e trombócitos foram também maiores nos peixes desse local. Os resultados sugerem que as alterações observadas no quadro hematológico se deveram à qualidade ambiental dos estuários e à sazonalidade.

This study investigated the hematological parameters of the tropical estuarine fish Centropomus parallelus and their use as a non-destructive biomarker for aquatic pollution. Individuals were collected, in summer and winter, at two estuaries, Cananéia (CAN) and São Vicente (SVE), and blood was extracted by caudal puncture. The evaluated parameters were hematocrit (Ht), red blood cells (RBC), Mean Corpuscular Volume (MCV), and the leukocyte (WBC) and thrombocyte counts. Fishes from CAN showed higher values of absolute number of thrombocytes in the summer. The fishes from SVE presented lower values of Ht and MCV in winter. Comparing the hematological parameters of fishes from these two sites, Ht, MCV, WBC and RBC were higher in fishes from SVE in the summer, whereas during the winter, Ht and thrombocytes were higher in animals from SVE. The results allow attributing the changes in the blood of fishes to seasonality and the presence of contaminants.

The aquatic environment receives many contaminants that can induce damages at the molecular, biochemical, cellular and physiological levels. Centropomus parallelus , an important food resource for local populations, is a predator fish that feeds on small fishes and benthic invertebrates, thus being vulnerable to the bioconcentration and biomagnification processes. This study aimed to evaluate cytogenotoxic responses in erythrocytes from C. parallelus juveniles collected in the Cananéia and São Vicente estuaries, both in winter and in summer. After anesthesia, blood samples were collected by caudal puncture. Blood smears were prepared on glass slides and stained with May-Grünwald-Giemsa dye. Two thousand cells were analyzed per slide (1000x), and nuclear abnormalities (NA) and micronuclei (MN) were scored. The São Vicente sample showed MN and NA frequencies (%/1000 cells) of 0.325 and 3.575, in winter, and of 0.125 and 2.935 in summer respectively; the Cananéia sample showed frequencies of 0.0325 and 0.03, in winter, and of 0.065 and 0.355 in summer, respectively. The rates found in São Vicente were significantly higher than those found in Cananéia, evidencing that the levels of pollution in that estuary were high enough to induce genetic damages.