Mercury Exposure

Were our participants exposed to high levels of mercury?

No, only around 5% of the people who ate fish from the Grand Lake watershed and participated in our study had mercury levels in hair that exceeded 1 part per million (ppm). This guideline was developed to protect unborn and young children. Our findings are consistent with other studies that show around 5% of the U.S. population has hair mercury levels above the guideline.

What types of fish contributed most to mercury exposure?

Our results suggest that among people who regularly ate fish from the Grand Lake watershed, around half of the mercury in their diet came from local fish, mainly catfish and bass. Around 40% came from saltwater fish, primarily from store-bought tuna.

Was mercury exposure higher in certain seasons?

We observed slightly higher hair mercury levels in fall and summer than in winter and spring. These differences did not seem to caused by our participants eating more fish in these two seasons. In fact, fish consumption was lower in the fall than in the other 3 seasons. There may be seasonal differences in mercury levels in the fish or differences in the types of fish people ate at different times of year.