With Mercury Found in Salmon, is Salmon Safe to Eat?

For those people who enjoy eating Salmon, care should be taken because salmon bioaccumulate the metal mercury. Bioaccumulation is simply the building up over time of a toxin, like mercury, that remains in the body without being flushed out. Salmon aren't the only creatures to be affected by mercury, but due to the popularity of Salmon, it gets a lot of attention. Salmon is still safe to eat, but only in moderation. Most cities and health departments post notices about how frequently salmon from area waters can be eaten. Pregnant women are especially sensitive to the effects of mercury and therefore need to exercise extreme caution for the health of their baby.

Mercury can be found almost anywhere in nature, so it isn't a purely human created pollution. Certain chemicals and products that are burned, like coal, give off mercury vapor that dissipates into the atmosphere. Then precipitation brings it back down to earth where it collects on the land, in streams and in the oceans. Fish absorb mercury when they filter tainted water through their gills and eat other organisms that also contain mercury. Since organisms, including humans, bioaccumulate mercury, the more things they eat that already contain mercury means the more mercury they'll end up with in their own system. Elemental mercury isn't actually absorbed, but when it's transformed into methyl mercury, it becomes a toxic poison.

Because of methyl mercury's ability to get into almost all water bodies, fish are very susceptible to bioaccumulation, and since many fish are predatory and eat other fish, they can contain a significant amount of mercury. Then when people catch them and consume them, the person now has all of the mercury from each fish that was eaten by the fish they just ate. That can be a lot of mercury. This is the reason precautions must be taken when eating seafood, especially salmon.

The FDA decided to make 1 part per million (PPM) of mercury an allowable level to prevent toxicity in humans. Scientists regularly test samples of fish to gauge the mercury levels and then post suggested consumption rates based on these levels. If mercury poisoning is suspected, a blood test or test on hair can determine the severity of toxicity. Symptoms of mercury poisoning depend on the levels in the body. The symptoms at first are mild with numbness and difficulty walking. The more mercury, the more severe the symptoms, weakness, fatigue, headaches and in the worst cases, death. Pregnant women easily pass the mercury through the placenta straight to the fetus. Basically, salmon, and most other fish, should only be eaten no more than once a week or even less frequently, to assure a limited level of mercury consumption.