Clean, safe tap water is a necessity. However, we’re seeing more and more news about water quality issues like lead, PFAS and PFOA, and microplastics that can make us question how safe our drinking water really is.
These concerns also bring up another question about the safety of a specific heavy metal that is sometimes found in tap water: mercury.
Mercury is a highly poisonous element that can be found naturally in the earth and pollutes our environment through industrial processes. Scarily enough, there’s evidence that almost everybody in the world has at least trace amounts of methylmercury in their bodies. So where is it coming from, and what can you do about it? Let’s talk about the possibility of mercury in drinking water, and whether or not you should be concerned.
What is mercury?
Mercury is a naturally occurring heavy metal found in elements like rock, soil, and water. Even though it can be found naturally in the earth, industrial processes like fossil fuel burning, mining, and manufacturing can also increase the amount of mercury released in the air, water, and soil. If not properly managed, these processes can introduce mercury into bodies of water, contributing to contamination that affects our water and our food supplies.
There are three different forms of mercury:
- Elemental: a liquid metal form of mercury
- Organic: a combination of mercury and carbon
- Inorganic: a combination of mercury with elements like chlorine or oxygen to form solid salts
Risks of exposures to mercury
Mercury is incredibly poisonous. In fact, the World Health Organization considers mercury one of the most harmful substances for human health.
All three forms of mercury (elemental, organic, and inorganic) can be dangerous when ingested or inhaled. For example, people can sometimes inhale elemental mercury vapor if they work in industries that use mercury (for example, the manufacturing of batteries, medical appliances, or paint). If it is inhaled as mercury vapor, it can cause issues like cough, shortness of breath, nausea, vomiting, and headaches.
However, organic mercury in particular is especially dangerous when it’s in the firm methylmercury. Methylmercury is formed when bacteria react with mercury in the environment. This particularly poisonous mercury form can pollute waterways and infiltrate our food systems. In fact, this form of mercury is often found in large fish like swordfish, tilefish, and king mackerel due to environmental contamination. Young children and fetuses are especially at risk of methylmercury poisoning since it can cause damage to the central nervous system, which is why it is often recommended for expectant mothers to avoid these fish in their diet.
Methylmercury poisoning can be very serious. Symptoms are often neurological and can even be permanent. Some symptoms include:
- Blindness
- Deafness
- Impaired mental functioning
- An increased risk of cerebral palsy
- Stunted growth and development
- Lung problems
How worried should I be about mercury in drinking water?
Because the effects of mercury exposure can be so serious, and since mercury is so prevalent in the environment and via pollution, it’s understandable to be concerned about the potential of mercury in your tap water.
The good news is that mercury contamination in tap water is fairly low. Even though mercury naturally occurs in rocks and soil, most major health organizations do not consider this level of mercury exposure a health threat for adults.
Furthermore, the Environmental Protection Agency (EPA) has also set a maximum contaminant limit of 2 parts per billion for inorganic mercury in drinking water. As a result, water treatment and distribution facilities around the country are required to treat their tap water and ensure that it doesn’t exceed these guidelines. Mercury can be filtered out in various ways, including activated carbon filtration and reverse osmosis, so that the water can meet drinking water standards.
As a result, mercury water contamination, while scary, is not the biggest risk in our drinking water. In fact, according to the EPA, the biggest risk of mercury exposure actually comes from fish, not drinking water.
With this said, however, this doesn’t necessarily mean that you should never have to worry about it at all. Contamination at levels above the EPA’s guidelines, while rare, can still happen. For example, in 2022, high levels of mercury were found in a sink at the Pearl Harbor Kai Elementary School in Oahu, Hawaii.
There is also the potential risk of major environmental disasters. This was highlighted in a major instance of mercury poisoning in the water supply of Grassy Narrows First Nation in Ontario in the 1960s and 1970s due to nearby industrial activities. Even today, a whopping 90% of the population in Grassy Narrows has shown signs of mercury poisoning.
Additionally, there is also the risk of high mercury levels if you are getting your water from an untested source! For example, people who rely on private wells for their water may be more at risk of mercury contamination than if they are getting their water from a local/municipal water supply that is regularly tested.
Finally, it’s again important to note that infants and fetuses are especially susceptible to negative health effects from methylmercury. Even if the levels present in the water are considered okay for adults, it’s well worth taking a closer look to protect the younger members of your family.
Solution: Filter your tap water before you drink it.
Mercury contamination is a serious issue linked to serious health effects. So even though mercury contamination is not one of the most prevalent and widespread issues in our drinking water supply, it’s still important to stay vigilant about it, particularly if you live near an industrial area and/or have young children.
So how can you go about removing mercury from your drinking water? Start by investing in a high-quality water filtering system that has been third-party tested to remove mercury. Both the LARQ Bottle Filtered or LARQ Pitcher PureVis feature a Nano Zero filter with zerovalent iron technology that attracts and traps heavy metals like mercury and lead. By running your water through this filtering system first, you can keep those dangerous mercury, lead, and even heavy metals out of the water that you drink for a clean and worry-free sip of hydration whenever you need it.