Mercury is a naturally occurring element released to the atmosphere by human activities - approximately 4000 metric tons each year resulting from coal combustion, gold mining, and other industrial processes. Coastal fog, like the kind we have in California, acts as a sponge for methylmercury emissions from the ocean, and when this fog moves onshore it can enter the food web on land. My research on mountain lions in the Santa Cruz area showed that they had mercury concentrations that approached toxicological thresholds. Deer, which are the main food source of mountain lions, also contained higher concentrations. Lichen also showed similar enhancements in mercury, which strongly suggested an atmospheric source (i.e. fog) since lichen only absorbs materials from the air. Although fog makes up a small portion of the water inputs to the Central Coast, it may play an outsized role in cycling mercury from the ocean to the land. The question for today: is this mercury also affecting the produce grown along coastal California, and if so, by how much?