By Alex Bakirdan
The man-made chemical known as 1,4 dioxane has been making waves in the news over the past few years after being discovered as a major pollutant in several regions across the country. Long Island is one of the places hardest hit by 1,4 dioxane pollution, and removing it from Long Island’s tap water has become a high priority as the pollutant is suspected to cause several different types of cancer. It is listed as a probable human carcinogen based on the results of animal testing, but as of yet there have been no long-term studies on its effect on humans.
But what is 1,4 dioxane? How did it get into American water supplies? And what can ordinary Americans do to avoid the pollutant as much as possible?
What Is 1,4 Dioxane and where is it found?
1,4 Dioxane is a man-made chemical, one that mixes seamlessly with water, so it is impossible to detect it in water with the naked eye. Its original use was as a stabilizing agent for various solvents and products including TCA. This means it was typically present in order to prevent the solvent from degrading. In other words, it prevents the solvent from undergoing a chemical change that prevents the solvent from working in its intended way. It was also originally found in many products like paints and inks, but it has mostly been removed from these over time.
But that isn’t the only place that 1,4 Dioxane had been used.
It’s found in many household cleaning products such as dish soaps and detergents, along with various personal hygiene products like shampoos. Some examples of daily household products that contain 1,4 dioxane include Tide Original Detergent and Gain Original Detergent as well as Dawn dish soap. Most detergents and dish soaps as well as many hand soaps, body washes and shampoos contain the chemical. While it isn’t extremely dangerous through skin contact alone, the runoff from the shampoo makes its way into the local water supply, and this is where the problem lies. The CDC’s Agency for Toxic Substances and Disease Registry created a public health statement on 1,4 Dioxane which explores exactly how regular people might ingest the substance and the dangers that it poses.
Why is 1,4 Dioxane dangerous?
While the chemical is believed to be a carcinogen, the federal government has never given it a Maximum Contaminant Level (MCL). Since it does not have an MCL this means that public drinking water systems are not required to regularly test for it. Despite not setting an MCL, the Environmental Protection Agency (EPA) has calculated that the maximum recommended safe limit is 0.35 micrograms per liter, or 0.35 parts 1,4 dioxane for every billion parts water.
But consuming even slightly more than these small amounts daily may lead to an increased risk of cancer in the long run. This means that areas in which the water exceeds the maximum safe guidelines are areas potentially at risk of seeing increased cancer rates. What makes the chemical more dangerous is that it is not filtered out by the standard water treatment plans employed at water treatment facilities.
It does not easily break down in the natural environment, meaning that once it enters an ecosystem, it will not go away on its own. It is also known to leach into groundwater relatively easily, and as such, places like Long Island’s aquifers have been contaminated by the chemical. Knowing that the problem exists doesn’t help an ordinary citizen much; they will still have to use their tap water regularly for things such as cooking and drinking, but the state of New York, along with several other states across the country, has started to take steps to attack the problem.
How might someone accidentally consume 1,4 Dioxane?
1,4 Dioxane is a believed carcinogen, which means that scientists believe exposure causes cancer, specifically cancer of the liver and kidneys. But how might an unaware average Joe consume the chemical? There are three main ways, according to the National Center for Biotechnology Information (NCBI).
The first of the three ways is inhalation, which is by far the most dangerous but also the least likely to occur to the average person. Inhalation of 1,4 dioxane, over a short period of time causes irritation in the eyes, nose and throat. Large periods or amounts of exposure will result in severe damage to the liver and kidneys as well as the respiratory system. Since it is typically only found in the air at places where it is being produced or used as a solvent however, this type of exposure is more likely to impact workers who are in factories that use it or who spray solvents like pesticides that contain it.
The second way, through drinking it, poses less of an immediate and drastic threat, but this makes it far more likely for regular people to drink it unknowingly over an extended period of time. Let’s look at a hypothetical situation to see how this could happen to a regular American. Steve, our hypothetical American, lives on Long Island, one of the areas with the worst levels of 1,4 Dioxane pollution in the country. Steve knows that he needs to stay hydrated and so every day he makes sure to drink plenty of water.
In that water however, he is unknowingly drinking 1,4 Dioxane. Since the chemical is odorless and colorless at the levels found in water, there’s no way for him to tell that the chemical is in his water just by looking at it. The good news for our hypothetical American is that after 1,4 dioxane enters the body through the digestive system it is broken down into other chemicals and quickly leaves the body. The bad news is that long-term exposure that comes from drinking the contaminated water day after day can impact the liver and the kidneys, the two parts of the body that do this work to filter the toxins out. Steve is asking his liver and kidneys to filter out 1,4 dioxane every day even without knowing he is doing so.
Drinking water is the most troubling way in which the average American can be exposed to 1,4 dioxane as it is the one that most people have the least control over. Steps are being taken by local and state governments across the country to regulate and reduce the problem and by using the EWG’s interactive map people can see if there is 1,4 dioxane is in the water where they live. Drinking bottled water is an option that can help people avoid 1,4 dioxane, but is both more expensive and creates plastic pollution which damages the ecosystem in other ways.
The third way in which someone may be exposed to 1,4 dioxane is through the skin. While studies have shown that 1,4 dioxane can enter the body through the skin, most of it will evaporate before it absorbs into the skin. It is also easier to avoid 1,4 dioxane entering through the skin simply by limiting the use of cosmetics, detergents and bath products that contain the chemical. To identify which products may contain 1,4 dioxane, the National Institutes of Health (NIH) has created a helpful list.
When picking out products at the store, people should look for the chemicals polyethylene glycol (PEG), polyethylene, polyoxyethylene, and oxynol-. These are the ingredients that the NIH has identified as most likely to contain 1,4 dioxane and as such are best avoided by cautious consumers.
Insert image/chart of example products that contain 1,4 dioxane
Where is the problem? What is being done about it?
Over 1/5th of all U.S. drinking water now contains 1,4 dioxane, and according to the Environmental Working Group (EWG) more than 7 million Americans in 27 states are getting water from sources that contain more than the maximum safe limit for lifetime cancer risk. Some places in Long Island, such as the Water Authority of Western Nassau which serves about 120,000 people, have reported 1,4 dioxane levels as high as 12.0 ug/L which is an alarming 34 times the maximum safe level recommended by the EPA and the state of New York.
Long Island as a whole is considered one of the hotspots for the issue, with 36 of the area’s water districts reporting levels over that of the EPA’s recommended maximum according to a study conducted by Citizens Campaign for the Environment. Other areas in the country that have faced serious problems with 1,4 dioxane pollution include Los Angeles County in southern California and the Cape Fear area in North Carolina. The good news is that each area has begun to tackle the problem with varying degrees of success.
New York has begun to take action against 1,4 dioxane in the past year, and in December of 2019, Governor Cuomo signed a bill into law that will make it illegal for products such as household cleaners, soaps, detergents and shampoos to contain anymore than trace amounts of 1,4 dioxane. The bill will not take effect until 2022 however, meaning the products will remain on the shelves in their current form for another two years.