Last Updated on January 4, 2022
Over the past several decades there has been a growing awareness of mercury in commercially available fish. In fact, mercury levels have climbed 30 percent in the last 20 years in the Northern Pacific alone. Pregnant women, for example, are admonished to only consume a certain amount of fish. However, little thought is given to how the mercury ended up in the water in the first place.
The path of mercury from its primary sources in power plants, into the water, and then into our bodies through both drinking water and eating fish, is a curious one. It is also one that we must understand if we are to come up with sensible solutions for the very real problem of mercury contamination in our oceans, rivers, and lakes.
It is not necessary to be a climate doomsayer or a green fanatic to understand the importance of keeping toxic chemicals out of the water. In fact, an outsized emphasis on global temperature changes can divert attention away from arguably more pressing issues like mercury in the water.
Indeed, there are very sensible solutions to this problem that do not require massive reductions in the Western standard of living or unreliable and arcane technologies not ready for prime time.
Just How Bad Is Mercury in the Environment?
Because we are so inundated with environmental doomsaying, it can be hard to know what is worth worrying about and what is simply noise. Mercury in the air, land, and water is certainly a very real concern, particularly with regard to the contamination of seafood, which makes up a significant protein source for billions of people around the world.
But if this weren’t disturbing enough, there is also mercury in the water that we drink. Fortunately, it is possible to remove the mercury from your water supply using reverse osmosis filters, distillation, GAC filters, and sub-micron filters.
The effects of mercury consumption are not abstract nor are they anything to trifle with. For example, you probably know that women are supposed to avoid eating too much fish during pregnancy because of mercury contamination.
What you might not know, however, is that it is estimated that 6% to 8% of the 16-to-49-year-old women in America have critical levels of mercury in their bloodstream. For certain segments of the population, this percentage jumps to 15 percent.
We have no method of removing mercury from the fish, however. All we can do is avoid the more dangerous fish (or eat them sparingly) and work to ensure that less mercury is emitted into the environment in the first place. The latter is an arduous task, but there is much reason to be hopeful that the momentum is going in the right direction.
Finally, fish and drinking water are not the only ways that we come into contact with dangerous levels of mercury. Many thermometers still contain mercury and are a source of poisoning for many who continue to use broken thermometers.
Mexican novelty jewelry is known to contain mercury, as are a number of other consumer products such as barometers and switches, but also in a growing number of cosmetics. Gold mining is another source of exposure and the fillings in your teeth might also be slowly giving you mercury poisoning — it can no longer be dismissed as an urban legend.
The effects of mercury poisoning can easily be debilitating, causing a loss of sight and hearing, or even fatal. Palliative treatments can be made, but mercury poisoning is a very serious illness that should be avoided at all costs.
Perhaps most troubling, exposure to mercury in infancy or in utero can lead to developmental problems that follow one throughout life. This is why it is absolutely essential for new and expecting mothers to err on the side of caution when it comes to consuming fish, particularly those known to be vectors for mercury poisoning.
This might all sound a little far-fetched, but the most common cause of mercury poisoning is the overconsumption of contaminated fish. Hundreds of thousands of pregnant women are impacted by this every year, to say nothing of how many others are suffering from more generalized symptoms of mercury poisoning without knowing it.
If you think you have symptoms of mercury poisoning, a quick audit of your diet might be one of the fastest ways to know if this is a reasonable cause of your symptoms. If so, consider seeing a doctor and submitting a urine test to determine the amount of mercury in your bloodstream.
Where Does the Mercury Come From?
Mercury comes from three primary sources. The first is anthropogenic, or mercury that is emitted into the environment as a result of human activity. The primary vector for mercury in the environment through anthropogenic sources is coal-fired power plants, with this accounting for 50 percent of mercury emissions in the United States.
However, the bulk of mercury is emitted into the environment by economically poor countries. East and Southeastern Asia account for 39 percent of all mercury emissions around the world, with Sub-Saharan Africa accounting for 16.1 percent and Latin America accounting for 12.5 percent. All told, these three regions are producing two-thirds of all mercury emissions around the world.
The mercury in the coal is natural, not man-made. When the coal is taken out of the ground, a lot of other materials are taken out with it, both in the coal and as a result of extracting the coal. Mercury is one of those “other materials” that come out with coal.
The path from coal-fired power plants is relatively straightforward: The mercury is emitted into the air, where it enters the water cycle and is rained into the oceans, rivers and streams. However, there is far more mercury than we can account for in the fish. This is how we know that fish are getting their mercury from sources other than coal-fired power plants. This brings us to the second form of mercury emissions.
The second source is natural sources of mercury, which account for about 10 percent of all the mercury in the environment. Volcanos, forest fires, and ore are all sources of mercury in the environment that are not man-made.
In fact, because there is naturally occurring mercury in the environment, your body is capable of processing very small amounts without issue. The problem is when the mercury concentration becomes too high or concentrated.
The biggest source of mercury, however, is one that you likely hadn’t considered before now: reemissions.
This is when mercury, which has already been introduced into the environment by human activity, is re-released by other activity, be it human or otherwise. This accounts for the remaining 60 percent of mercury emissions.
Remissions are worth taking a second to consider because they’re a sort of compounded interest with regard to mercury emissions. The mercury is emitted from its original source, locked somewhere in the environment, re-released, and then locked somewhere else again. So the problem of reemissions is one that is far greater than the problem of original emission — and it accounts for nearly two-thirds of all emissions.
Fortunately, mercury reemissions represent one of the easiest ways to make a dent in mercury in the air and water. Various emerging technologies make it easier to control the amount of mercury released in the first place, as well as control the amount of mercury that is reemitted once it is absorbed into things like limestone and gypsum.
Mercury in the fish also comes from another unlikely source: aquaculture and farmed fish. Farmed fish are often fed food that has been treated with mercury. This makes them contaminated but also means that there is effectively mercury being dumped into the water, to say nothing of mercury emissions from the fish food plants and the emissions from the power plants needed to fuel them.