Distribution and Risk Assessment of Polycyclic Aromatic Hydrocarbons in Mussels from the Middle and Lower Main Stream of Huaihe River

[ Object] The aim was to discuss the pollution status of polycyclic aromatic hydrocarbons （PAHs） in mussels from the middle and lower main stream of Huaihe River, which will provide a scientific basis for dietary safety of mussels. [ Method] Suspended matter, sediment, and mussel samples were collected from Wuxiaojie and Fushanji in middle and lower reaches of Huaihe River. All samples were extracted with Soxhlet, separated through Silica GeI-Al2O3 column, and determined by GC-MS, and then 16 typical PAHs contents in the prior table listed by American EPA were obtained. [ Result] The results indicated that total PAHs concentrations in suspended matters and sediments of Wuxiaojie were significantly higher than those in Fushanji respectively. However, PAHs concentrations in mussels of the two samplings showed little difference; as for single PAH component, low-ring PAHs were more advantaged in suspended matters of two sampling sites, while high-ring PAHs were more advantaged in mussels. PAHs in sediments of Wuxiaojie assumed low-ring aspect, though PAHs in sediments of Fushanji assumed high-ring aspect. [ Conclusion] In spite of that sediments and mussels were not yet contaminated according to the ecological risk assessment of PAHs, its potential hazards couldn＇t be ignored any more.

Epidemiology and natural history of hepatitis C virus infection

Hepatitis C virus(HCV)affects 130-210 million people worldwide and is one of the major risk factors for hepatocellular carcinoma.Globally,at least one third of hepatocellular carcinoma cases are attributed to HCV infection,and 350000 people died from HCV related diseases per year.There is a great geographical variation of HCV infection globally,with risk factors for the HCV infection differing in various countries.The progression of chronic hepatitis C to end-stage liver disease also varies in different study populations.A long-term follow-up cohort enrolling participants with asymptomatic HCV infection is essential for elucidating the natural history of HCV-caused hepatocellular carcinoma,and for exploring potential seromarkers that have high predictability for risk of hepatocellular carcinoma.However,prospective cohorts comprising individuals with HCV infection are still uncommon.The risk evaluation of viral load elevation and associated liver disease/cancer in HCV(REVEAL-HCV)study has followed a cohort of 1095 residents seropositive for antibodies against hepatitis C virus living in seven townships in Taiwan for more than fifteen years.Most of them have acquired HCV infection through iatrogenic transmission routes.As the participants in the REVEALHCV study rarely receive antiviral therapies,it provides a unique opportunity to study the natural history of chronic HCV infection.In this review,the prevalence,risk factors and natural history of HCV infection are comprehensively reviewed.The study cohort,data collection,and findings on liver disease progression of the REVEAL-HCV study are described.