Study On The Analysis And Evaluation Of POPs In Fish From Dongting Lake

Persistent organic pollutants (POPs)are a class of synthetic compounds, have highly toxic, persistent, bioaccumulative, can migrate long distances by the atmosphere, at last deposited in the environment, which may have a harmful effect to human health. Spiratory, skin, dietary intake are the main ways of humans’POPs exposure. Dietary exposure of POPs is the most important way of human exposure, while fish intake of POPs is a major source of exposure in human diet. Dongting Lake is the second largest freshwater lake of China and an important fish and aquatic habitat of the Yangtze River, which the annual production of fish is37,900tons. In this study, the level of dioxins (PCDD/Fs), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs) were analyzed in13kinds offish of the Dongting Lake’s water season and dry season. The results are as follows.1.In Dongting Lake water season and the dry season, The average concentration of PCDD/Fs were29.993and1.017pg/g ww, the range were5.787-198.36and0.368-3.276pg/g ww in fish respectively. The average concentration of DL-PCBs was87.837and58.285pg/g ww, the range were11.536-411.018and7.676-238.181pg/g ww, respectively. The mean of total TEQ of PCDD/Fs+DL-PCBs in fish were0.842and0.314WHO-TEQ/g ww, the range were0.110-5.619and0.081-1.095pg WHO-TEQ/g ww, respectively. The main of PCDD/Fs congeners were OCDD,2378-TCDF in fish. The highest concentration of DL-PCBs congeners was PCB118in Fish.12378-PeCD and23478-PeCDF have the largest percentage of total PCDD/Fs TEQ in water and dry season, respectively. PCB126has the largest percentage of total DL-PCBs TEQ was in both water and dry season. The concentration of PCDD/Fs in water season was significantly higher than the dry season, but the concentration of DL-PCBs was no different in the dry and the water season. The use of sodium pentachlorophenol in Dongting Lake maybe an important factor to affect PCDD/Fs concentration of fish.In Dongting Lake, PCDD/Fs TEQ of Guan fish was largest in13kinds offish, which is above the EU maximum limilit.2.1n Dongting Lake water season and the dry season, the average concentration of Indicative PCBs were421.7and294.4pg/g ww, the range were46.7-2209.2and35.5-1270.6pg/g ww, respectively. The concentration of indicative PCBs in the long snout catfish and catfish were very high in water and dry season. The main of indicative PCBs congeners were PCB28and PCB153. The concentration of indicative PCBs in fish is no different in Water and dry season. Feeding habits of fish may affect the content of indicative PCBs in fish, the level of indicative PCBs in carnivorous fish higher than herbivorous fish. The concentration of Indicative PCBs in fish was positively correlated with fat content of fish. The level of indicative PCBs in fish is far less than China’s "food contamination limited11. Compared with other areas of China, the content of indicative PCBs in fish is equal to freshwater fish, but lower than marine fish of our country and Europe and other developed industrialized countries.3.In Dongting Lake water season and the dry season, the average concentration of PBDEs were43.8and128.7pg/g ww, the range were21.3-488.0and19.6-419.6pg/g ww, respectively. The concentration of PBDEs in the long snout catfish and catfish were very high in water and dry season. The most main of PBDEs congeners were BDE-47in water season, and in dry season the most main was BDE-183, next was BDE-47.The concentration of PBDEs in fish was no different in Water and dry season. The habits offish may affect the content of PBDEs in fish, fish was positively correlated with fat content of fish, and the concentration of indicative PCBs in fish was positively correlated with PBDEs in fish. Levels of PBDEs in fish, compared to other regions at home and abroad, at a very low level.4.Assessing residents PCDD/Fs, PCBs, PBDEs dietary exposure by intake fish, we found PCDD/Fs, DL-PCBs dietary exposure by intake fish below the JECFA established provisional tolerable intake per month (PTMI)70pgWHO TEQ/kg bw and EUSCF developed tentative weekly tolerable intake (TWI)14pg WHO TEQ/kg bw. However, if urban residents intake Mateo Fish for a long time, may have health risks. Indicative PCBs, PBDEs exposure levels in water season were higher than the dry season, and the city residents’indicative PCBs, PBDEs exposure levels by fish were higher than rural residents. Compared with other parts of Asia, PCDD/Fs, DL-PCBs exposure by fish at a relatively low level, but compared with developed countries in Europe, PCDD/Fs, DL-PCBs exposure to slightly higher.