Mercury is in our fog, but what about our food?

 

COVID-19 update: While the pandemic has created unique challenges for conducting research, our team remains committed in doing as much as we can. As of now research is still planned to start September/October of 2020. By this time the fog season will be over and we will have maximum saturation of fog to test.

After discovering near toxic levels of mercury in the puma population, we now turn our attention to the agriculture and livestock of the central coast. As chemists we are skeptical by nature so while it is likely that all crops fall under the guidelines set by the FDA we feel everyone has a right to be sure.

We will be studying foods that have high potential to have concentrated mercury. Some factors that could affect mercury concentration are long grow time, high volumes of water to grow or have high levels of fat. Of particular interest to us will be dairies as we believe cheese has the highest potential to have concentrated mercury. However other foods will be explored as we refine our parameters for possible contamination. This is an important study to assess the risk of bioaccumulation in humans along the California coast as well as other coastal regions that have a similar ecosystem to ours.

The graph to the left shows the          % methylmercury (MMHg) as a fraction of total mercury in these samples. 

The BOR is Blue Oak Ranch (inland site) has much less methylmercury than AN (Ano Nuevo) and GR (Greyhound Rock), both coastal sites It is easy to see that samples from the coastal sites have a much higher proportion of total mercury as methylmercury compared to the inland sites. (See map below)

Results like these tell us that the atmosphere plays an important role in determining the amount of mercury in plants and lichen. The atmosphere could be shuttling the mercury from the ocean to land and our research hopes to determine the magnitude of this.