Potential Risk of Persistent Organic Pollutants

OCPs can cause a range of adverse human health effects, such as cancer, reproductive effects, and acute and chronic injury to the nervous system. Many previous investigations show that the increasing consumption of contaminated seafood has resulted in an elevated pollutants residual in human tissues compared with that in older generations (Asplund et al., 1994). The World Health Organization (WHO) and Food and Agriculture Organization (FAO) have proposed an acceptable daily intake (ADI) for DDTs at 5,000 ng/(kg d) (Zhulidov et al., 2002). For a 70-kg human, if he/she consumes 1 kg aquatic product a day from the Bohai Sea with a mean DDTs level of 199 or 52 ng/g, his/her daily intake dose is 2,850 ng/kg. This value is well below the proposed ADI. However, the ADIs of DDT are 400 and 600 ng/(kg d) in 

Canada and the USA respectively. Therefore, the DDTs residual level is about 6 times higher than that in Canada and 4 times higher than that in the USA. Similar guidelines do not exist for EHCH, but it is reported by the US DHHS (2005) that it has assigned a y-HCH oral reference dose of 300 ng/(kg-d). If it is presumed that a 70-kg person consumes 1 kg of mollusks from the Bohai Sea in view of the maximum y-HCH of 2.12 ng/g in Yingkou, his/her daily intake of HCHs is 31 ng/(kg-d), about 1/10 of the oral reference dose. 

Consequently, TEQs of PCDD/Fs and PCBs in Bohai Bay are summarized in Table 2.29. 

Sediment sample TEQpcdd TEQpcdp TEQpcb Reference 

The station located in Bohai Bay in the extension direction where the Nanpaiwu River enters 

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