Three of
the SSD-derived PNECs range from 0.94 to 1.8 μg/L, about a factor of two apart. To demonstrate the use of
SSD-based PNEC values and comprehensively estimate the regional ecological risk for cadmium in surface
water of the Bohai Sea, in the Liaodong Bay, Bohai Bay, and Laizhou Bay, China, the dissolved cadmium concentrations
were measured and obtained 753 valid data covering 190 stations from July 2006 to November
2007. Based on three ecological risk assessment approaches, namely hazard quotient (HQ), probabilistic
risk quotient and joint probability curve (JPC), the potential ecological risk of cadmium in surface water of
the Liaodong Bay, Bohai Bay, and Laizahou Bay were estimated. Overall, the ecological risk of cadmium to
aquatic ecosystem in the whole Bohai Sea was at acceptable ecological risk level, the order of ecological risk
was Liaodong Bay>Bohai Bay>Laizhou Bay. However, more concerns should be paid to aquatic ecological
risk in the Liaodong Bay which is the home of many steel, metallurgy and petrochemical industrial in China.