Risk assessment of cadmium contamination and dietary exposure in market aquatic products in one district of Shanghai

ObjectiveTo investigate the status of cadmium contamination in commercially sold aquatic products and to analyze the risk of dietary intake of cadmium among residents in one district of Shanghai.

MethodsMultistage sampling was used to collect 397 animal aquatic products from agricultural markets and supermarkets in 11 communities (townships), the District from 2018 to 2019.Cadmium content was tested according to national standard.The status of cadmium contamination was assessed by single factor pollution index(Pi)method.Risk of dietary intake of cadmium among residents was assessed by point evaluation method in combination with food consumption and dietary survey in 2013 and calculation of safe limits for cadmium in various aquatic diets(MOS).

ResultsThe detection rate of cadmium was 75.06% in the 397 animal aquatic products and the content of cadmium in 10 samples which crabs were totally exceeded the standard, accounting for 2.52%.The average contents of cadmium in crabs, bivalves which were higher than in shrimps(11.0 μg/kg), gastropods(7.6 μg/kg) and marine fish(3.8 μg/kg) were respectively 140.0 μg/kg and 90.0 μg/kg(χ²=186.41, P < 0.005), but no cadmium was detected in freshwater fish.The single factor pollution index(Pi) of crabs was 0.280 which meant light pollution and the Pi of other kinds of aquatic products was respectively under 0.100 that meant no cadmium contamination.The consumption of animal aquatic products was the highest in freshwater fish followed by shrimps, marine fish and crabs.The MOS of every kind of aquatic products is higher than 1 which meant cadmium intake from commercially sold animal products was an acceptable health risk for the population.

ConclusionThe risk level of cadmium intake by residents in the district through commercially sold animal aquatic products is relatively low, but the cadmium pollution status of commercially sold crustacean crabs should be vigilant, and the intake of crabs is advised to be reduced as far as possible.Relevant departments should also pay attention and strengthen monitoring and management in this regard.