Study On The Distribution Characteristic And The Toxicological Effects Of Mussel Of Polycyclic Aromatic Hydrocarbons (PAHs) Of The Typical Seawater In Yangpu Bay

Polycyclic aromatic hydrocarbons (PAHs) are a ubiquitous class of organic contaminants found throughout the marine environment, and is readily bioavailable and toxic toa range of marine invertebrates.To assess the characteristic of spatial and temporal distribution of PAHs in the surface seawater of Yangpu Bay,Hainan,the concentration of14polycyclic aromatic hydrocarbons (PAHs) in surface seawater from different sampling points has been investigated by UPLC. The toxicity effects of Benza[a]pyrene which exposed on the early larval of Pinctada martensii and the immunity toxicity effect on adult Pinctada martensii. was studied. The main conclusions are as follows:1) The total concentrations of PAHs in surface seawater of four sampling points in Yangpu bay were in the range of1934.16ng·L-1to4360.69ng·L-1.The concentration order from the highest to the lowest at different sampling points was Crude oil terminal pier> Gimhae Pulp Pier> Baimajing Pier> offloading pier. The total concentrations of PAHs in surface seawater at different four sampling period in Yangpu bay were in the range of2065.86ng L-1to8447.67ng·-1with the order from highest to lowest was February> November> August> May.The concentration of phenanthrene and pyrene were much higher than other components of PAHs. The concentration of phenanthrene was range of553.63ng·L-1to1543.65ng·L-1, and pyrene with range of352.90ng·L-1to1215.57ng·L-1in different sampling station.2-4-ring PAHs were abundant in sueface seawater, which rationwas the range of93.93%to97.03%. On the other hand,5and6-ring PAHs were rare, which range of2.97%to6.07%.According to the ratio of fluoranthene/pyrene (Flu/Pyr), we can conclude that the contaminate sources of PAHs mainly come from the crude oil pollution in Yangpu Bay, which indicated that there was a pontential ecotoxicological risk of PAHs in the surface seawater of Yangpu Bay.2) B[a]P had a significantly toxic effect on the morphology D-shaped veliger larvae of Pinctada martensii And larvae in4and10μg·L-1groups were much more sensitive than that in other groups. The morality was positive to the concentration of B[a]P in the range of1-10μg·L-1. B[a]P could significantly deform D-shaped veliger larvae. Moreover, with the increasing of concentration of B[a]P, the abnormal individual early appeared. Additionally, LC50gradually decreased and then kept a constant LC50of21.56μg·L-1at48h exposure period.The results indicated that B[a]P had negative effects on the development of D-shaped veliger larvae of Pinctada martensii and their populative structure. 3) B[a]P also can damage the non-specific immune defense system of Pinctada martensii.The number of blood cells, antibacterial activity and lysozyme activity in the serum of Pinctada martensii.was detected after exposure of B[a]P. B[a]P exposure resulted in immune modulation with significant reductions in the number of blood lymphocytes.There are significant dose-effect relationship. Meanwhile, the antibacterial activity and lysozyme activity of serum was also inhibited.There was no significant change of SOD activity in serum. Changes in the non-specific immune function and biochemical endpoints observed in ths study illustrate their potential use in assessing the subtle effect of B[a]P exposure.