Parental Exposure To Sunken Oil Impairs Reproduction And Embryonic Development In Sea Urchin

To study the effects of sunken oil on marine organisms and the genetic toxicity transferred from parents to offspring under different parental exposure,maternal exposure,paternal exposure and parental exposure were set up.The 380#fuel oil was used to simulate the sunken oil and Strongylocentrotus intermedius was selected as test organism.The overlying water and interstitial water were determined by ultraviolet spectrophotometry and gas chromatography-mass spectrometry(GC-MS).The results of fertilization ability of gametes and embryonic development of their offspring were analyzed combined with the concentration of TPH and polycyclic aromatic hydrocarbons(PAHs).The results showed that the concentration of TPH in the overlying water and interstitial water increased with the rise of the oiled-gravel column concentration,moreover,the TPH concentration in the interstitial water was higher than that in the overlying water.The trend of the growth inhibition rate and deformity rate of embryos were consistent with the trend of TPH.The maximum content of TPAH in oiled-gravel and overlying water were 10.277μg/g and 14.826μg/L,respectively.Phenanthrene was the most important part of PAHs.It indicated that sea urchin embryonic developmental delay and deformity were mainly caused by phenanthrene.The fertilization rate of the gametes remained above 98%,the GSI decreased and the maximum ovulation inhibition rate of female sea urchin was 50.89%after exposed to the overlying water and interstitial water for 7 days.It indicated that the parental exposure did not affect the fertilization ability of gametes.But a large number of smaller body,growth inhibition and deformity were found at the stage of embryos,demonstrating that the toxicity of sunken oil would pass through sea urchin gametes and resulting in morphological changes of offspring.The growth inhibition rate and deformity rate of the pluteus(exposure period 48h)were higher than that of the gastrula(exposure period 24h).The result showed that the effect of sunken oil would be amplified at pluteus stage.Therefore,sea urchin embryos can be applied to the extent of the damage and the early-warning of petroleum hydrocarbons pollution.The maximum inhibition rate appeared in paternal exposure and the minimum growth inhibition rate appeared in maternal exposure.The deformity rate of parental exposure embryos was highest.The result indicated that paternal and parental exposure would cause more serious genetic toxicity to the offspring than maternal exposure.The development of the offspring embryos can provide important scientific basis for marine ecological risk assessment,natural resource damage assessment and claims for oil spill accidents.