Bioavailability of Methylmercury in Rice Cereal and Fish

Undergraduate #177
Discipline: Chemistry and Chemical Sciences
Subcategory: Chemistry (not Biochemistry)

Genique Nicholas - University of the Virgin Islands
Co-Author(s): Wenbin Cui, Florida International University,FL

Methylmercury (MeHg) is known as a contaminant worldwide and a potent neurotoxin that is harmful to the neurodevelopment in infants. MeHg is formed from inorganic mercury by the action of microbes that live in aquatic systems and then bioaccumulated through the food chain. Traditionally, consumption of fish or fish based food was considered as the major pathway of MeHg exposure to human. However, the recent finding that rice could also accumulate MeHg in its grain prompted our interest in studying the MeHg level and bioavailability in rice and rice product due to the high consumption of rice product around the world, especially for human infants. Infants do not directly consume fish or rice, however, could still be exposed to MeHg due to the consumption of breast milk and rice or fish based baby food such as rice cereal. There is a very limited information available regarding MeHg in rice cereal and the potential exposure of infants to MeHg. Therefore, the main objectives for this research are to: 1) determine the amount of MeHg in rice cereals, 2) estimate the bioaccesibility of MeHg in rice cereals, and 3) compare the bioaccesibility of MeHg in rice cereal and fish. To achieve these goals, experiments have been designed and conducted. Twelve commercially available rice samples were purchased from a market and tested. Preliminary experiments have shown that rice cereals do contain considerable level of MeHg. The MeHg concentrations were recorded in ng/g. The results showed that the MeHg concentrations were lower than that of recorded concentrations for fish (ranging from 14.3±13.9 ng/g to 527.4±84.1 ng/g in sea food samples). The results show that out of the samples we tested the average MeHg concentration was 5.6±4.19 ng/g, and the average bioaccessibility was approximately 50%. Considering the great amounts of rice cereal consumed by infants, the MeHg intake through rice cereal may post potential health risk to infants.

Funder Acknowledgement(s): This research was funded by the NSF-REU Site grant No: 15560375.

Faculty Advisor: Yong Cai, cai@fiu.edu

Role: For this research, I conducted experiments, gathered literature, help to analyze the results of the experiments, and produced the poster.