RESUMEN
Mussels (Mytilus edulis) were continuously exposed to dispersed crude oil (0.015-0.25mg/l) for 7 months covering the whole gamete development cycle. After 1 month exposure to 0.25 mg oil/l, the level of alkali-labile phosphates (ALP) and the volume density of atretic oocytes in female gonads were higher than those in the gonads of control females, indicating that oil affected the level of vitellogenin-like proteins and gamete development. Spawning of mussels was induced after 7 months oil exposure. Parental oil exposure did not affect subsequent fertilization success in clean seawater but this was reduced in 0.25 mg oil/l. Parental exposure to 0.25 mg oil/l caused both slow development and a higher percentage of abnormalities in D-shell larvae 2 days post-fertilization; reduced growth 7 days post-fertilization. These effects were greatly enhanced when larval stages were maintained at 0.25 mg oil/l. Similar studies are warranted for risk assessment prognosis.
Asunto(s)
Petróleo/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Biomarcadores/metabolismo , Embrión no Mamífero/anomalías , Embrión no Mamífero/efectos de los fármacos , Femenino , Células Germinativas/efectos de los fármacos , Células Germinativas/crecimiento & desarrollo , Células Germinativas/patología , Gónadas/efectos de los fármacos , Gónadas/metabolismo , Gónadas/patología , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Masculino , Mytilus edulis , Petróleo/metabolismo , Medición de Riesgo , Vitelogeninas/metabolismo , Contaminantes Químicos del Agua/metabolismoRESUMEN
The single-cell microgel electrophoresis assay or the comet assay was used to evaluate DNA damage of dispersed crude oil on sea urchins (Strongylocentrotus droebachiensis) and mussels (Mytilus edulis L.). Sea urchins were exposed to 0.06 and 0.25 mg/L dispersed crude oil in a continuous flow system, while the mussels were exposed to 0.015, 0.06 and 0.25 mg/L dispersed crude oil. Sea urchin coelomocytes and mussel haemocytes were sampled after 4 and 5 weeks exposure, respectively. In the sea urchin coelomocytes, there was a significant concentration-related increase in the percentage of DNA in comet tail. In mussel haemocytes, there was a significantly higher percentage of DNA in comet tail for all treatments compared to the control. The responses were concentration-related up to 0.06 mg/L oil. The two highest exposure concentrations of mussels were not significantly different from each other. These results indicate that the comet assay can be used for biomonitoring of DNA damage in marine invertebrates following oil contamination.