Analies Dyjak, M.A. | Head of Policy and Perspectives

**Updated 9/21/2021 to include recent studies

What Is 1,4-Dioxane?

1,4-dioxane is a synthetic industrial chemical, typically used as a stabilizer for chlorinated solvents. It was historically used in the production of 1,1,1-trichloroethane (TCA), which was phased out in 1985 after scientists determined it to be an ozone-depleting substance. Today, 1,4-dioxane is not typically added directly to consumer products but can be an unintentional byproduct in certain plastics. It’s introduced as a trace contaminant in certain ingredients, most commonly detergents, foaming agents, emulsifiers and solvents, including Polyethylene Glycol or PEG.  

Is 1,4-Dioxane Regulated?

1,4-dioxane in drinking water is not federally regulated under the Safe Drinking Water Act, even though EPA has classified it as “likely to be carcinogenic to humans by all exposure routes.” There are health advisories in place but a Maximum Contaminant Level (MCL) does not exist. This means that unless a state has its own enforceable standard, utility providers are not required to remove it from drinking water. 1,4-dioxane is regulated by the Occupational Safety and Health Administration (OSHA) for indoor workplace air quality. 1,4-dioxane is on the fourth drinking water Contaminant Candidate List and is also part of the Third Unregulated Contaminant Monitoring Rule. In 2019, New York State became the first state to regulate 1,4-Dioxane by establishing Maximum Contaminant Limits (MCL) of 10 ppb in cosmetics, and 2 ppb in personal care and household cleaning products by 12/31/2022, which will be further reduced to 1 ppb by 12/31/2023.  

How Does 1,4-Dioxane Enter Drinking Water?

1,4-dioxane has contaminated drinking water through both groundwater and surface water. Many instances of groundwater contamination are a result of 1,4-dioxane being used in various manufacturing processes. According to the Agency for Toxic Substances and Disease Registry, 1,4-dioxane can easily travel into groundwater because it is extremely soluble in water and does not stick to soil particles. 

1,4-dioxane contamination on Long Island, New York was a result of routine spills or direct disposal of solvents to the ground from manufacturing operations between the 1950s to the 1990s. 

1,4-dioxane was used in the manufacture of medical filters in Ann Arbor, Michigan. The methods of waste disposal used between 1966 to 1986 resulted in 1,4-dioxane being released into the environment, causing widespread groundwater contamination. 1,4-dioxane in drinking water continues to be a concern for local residents, even decades after the pollution was first discovered and remediation was to have been taking place. 

1,4-Dioxane has also been released into surface water, both into rivers or public sewage systems. Sources of contamination include effluent from industrial facilities as well as wastewater treatment plants.   

1,4-Dioxane Health Effects In Drinking Water

1,4-dioxane can harm the eyes, skin, lungs, liver, and kidneys. As previously stated, 1,4-Dioxane is classified by the US EPA as a likely human carcinogen. Like other contaminants, the dose and duration of exposure affect the likelihood and severity of adverse 1,4-dioxane health effects.

Why is 1,4-Dioxane So Hard To Remove From Drinking Water?

1,4-Dioxane is completely soluble in water. It dissolves completely, even at high concentrations. It also does not readily evaporate. Traditional treatment methods are ineffective at removing 1,4-Dioxane from drinking water, so a few larger municipalities have begun to incorporate specialized methods for 1,4-Dioxane removal in their processes. These can be prohibitively expensive for smaller municipal water suppliers, so there is not likely to be a widespread solution for 1,4-Dioxane removal implemented any time soon.  

What Can I Do if I Have 1,4-Dioxane in My Water?

There are no federal testing standards for 1,4-Dioxane, so we are unable to provide removal data. Hydroviv’s filters have however been tested and certified by NSF to remove VOC’s with similar chemical properties to 1,4-Dioxane. Most submicron pore size carbon block filters are able to address 1,4-dioxane, with the exception of granular activated carbon. A slower flow rate will also assist the carbon block filter by ensuring enough contact time with the 1,4-Dioxane and the filtration media. For example, Hydroviv drinking water filters incorporate carbon into our submicron block and at our 1 gallon/minute flow rate.

*Updated April 10, 2024 to include new information on PFAS regulation.

Analies Dyjak  |  Policy Nerd 

Per and Polyfluoroalkyl Substances (PFAS) have received a ton of media attention in the past few years. PFAS are a category of toxic contaminants that have invaded public and private drinking water systems across the entire country. This article discusses what PFAS actually are, where they come from, their health effects, and if they are regulated by the federal government. 

What Are Per and Polyfluoroalkyl Substances (PFAS)?

Per and Polyfluoroalkyl Substances (PFAS) are a category of “emerging contaminants,” which means they have been detected in the environment but the risk to human health is not well-understood. GenX, PFOA, and PFOS are all common variations that fall under the category of PFAS. Chemical manufacturing companies (including DuPont, Chemours, and 3M) have been using variations of these chemicals in industrial and consumer products since the early 1950’s. Scotchgard, Teflon, firefighting foam, metal plating, heat/water repellent products, and stain resistant fabrics are associated with this category of contaminant. PFAS are extremely persistent in the environment, which means they do not readily degrade. 

Are Per and Polyfluoroalkyl Substances (PFAS) Regulated?

Yes. On April 10, 2024, the US EPA has announced drinking water standards to limit exposure to 6 types of PFAS chemicals. In addition, a few states have  established their own regulations for PFAS. Prior to this, the EPA established health advisory levels for PFOA and PFOA, but these levels were not actionable or enforceable. 

What Are The Health Effects of Per and Polyfluoroalkyl Substances (PFAS)?

According to a study by the Agency for Toxic Substances and Disease Registry (ATSDR), PFAS exposure is associated with various adverse health effects, including an increased risk of cancer (kidney and testicular), lowered fertility rates, increased cholesterol, and developmental issues in infants and young children. A new study out of The Yale School of Public Health recently found that exposure to PFAS increases the risk of miscarriage by 80-120% in pregnant women. The Centers for Disease Control also issued a disclosure regarding a potential intersection between PFAS and COVID-19. This is largely in part due to the fact that exposure to PFAS decreases your body's ability to fight disease, and impacts your body's ability to respond to vaccines. 

Researchers at the University of California, Berkeley, published some of the most compelling research to date in April of 2020. The researchers studied birth outcomes in Minnesota from 2002-2011, where high levels of PFAS compounds were detected in East Minneapolis and Saint Paul drinking water. The researchers found that exposure to PFAS chemicals can cause low birth weights and preterm births, both of which have been associated with long term developmental issues. The Berkeley team determined "a direct causal relationship between filtration of drinking water containing high levels of exposure to PFAS and improved reproductive outcomes."

How Are Humans Exposed To Per and Polyfluoroalkyl Substances (PFAS)?

• Consumption of contaminated drinking water
• Consumption of fish and shellfish that may contain PFAS through bioaccumulation
• Industrial exposure to workers who manufacture PFAS

What Are Public Officials Doing About Per and Polyfluoroalkyl Substances (PFAS)?

EPA set a Lifetime Health Advisory Level of 70 parts per trillion for both PFOA and PFOS. The rule of thumb for PFAS is that the sum of the category of contaminants should be no higher than 70 parts per trillion. ATSDR believes this level should be reduced to 20 parts per trillion for drinking water. Again, Lifetime Health Advisory Levels and Minimum Risk Levels are non-enforceable limits that municipalities are not required to follow.

Do All Water Filters Remove PFAS?

No. Duke University and NC State University tested various water filtration brands and their ability to remove PFAS from drinking water. We were surprised to see how poorly major brands like Brita, Pur, Berkey, Whirlpool, and GE performed in this study. If you'd like to see how Hydroviv filters stacked up, check out the results here. Some of the brands even added PFAS chemicals back into the filtered water, likely due to cheap/low quality media and over-saturation. 

If you have any questions about PFAS in your drinking water, feel free to drop us a line at hello@hydroviv.com. You can also visit hydroviv.com and use our live chat feature. 

Analies Dyjak | Water Nerd  
Updated March 3, 2022 to include current data

For Hydroviv's assessment of Washington, DC's tap water, we collected water quality test data from DC Water's annual Consumer Confidence Report and the U.S. Environmental Protection Agency. We cross referenced their water quality data with toxicity studies in scientific and medical literature. The water filters that we sell at Hydroviv are optimized to filter out contaminants that are found in DC's drinking water.

Where Does DC Source Its Drinking Water?

DC Water purchases water from The Washington Aqueduct, which is owned and operated by the Army Corps of Engineers. The Washington Aqueduct draws 140 million gallons of water from the Potomac River everyday. DC Water then properly treats the water before distribution. 

Lead In DC Drinking Water

Lead has been a major problem in DC's drinking water for several decades. DC had a major lead crisis in the early 2000’s, so this contaminant is something we like to look out for. According to this years report, 10% of the samples tested for lead had concentrations over 3 parts per billion. There were 118 samples collected over a monitoring period from January to June, and 3 samples had lead levels over the EPA action level of 15 parts per billion. EPA, CDC, and the American Academy of Pediatrics all acknowledge that there is no safe level of lead for children. It’s also important to note that many of DC’s homes were built with lead plumbing and lead fixtures, so the relatively small sample size may not necessarily reflect the scope of the lead problem in DC. We've linked a map of the identified lead service lines throughout Washington, DC. We highly recommend that DC residents take advantage of the city’s free lead test program. To get a free lead test kit, just call 202-612-3440 or email leadtest@dcwater.com.

Disinfection Byproducts in DC Drinking Water

Next is Disinfection byproducts or DBPs. DBPs form when chlorine-based disinfectants react with organic matter in incoming water. DBPs are split into two categories: Total Trihalomethanes (TTHMs) and Haloacetic Acids-5 (HAA5). Concentrations of TTHMs averaged 52 parts per billion, but levels were detected as high as 66 parts per billion in DC water. HAA5 concentrations averaged 33 parts per billion. While Washington D.C.'s water quality is technically still in compliance of loose EPA standards, these levels are definitely high. www.hydroviv.com to talk to a Water Nerd on our live chat feature.

Other Articles We Think You Might Enjoy:
Lead Contamination In Drinking Water 
Disinfection Byproducts In Drinking Water: What You Need To Know
Chloramine Vs. Chlorine: What You Need To Know

Analies Dyjak  |  Policy Nerd

The Agency for Toxic Substances and Disease Registry (ATSDR) just released a draft toxicological profile for Perfluoroalkyl Substances such as PFOA and PFOS. This category of emerging contaminants have flooded news headlines this past year, even though they've been persistent in the environment since the 1950’s. PFOA and PFOS are ingredients used in the production of non-stick materials like Scotchgaurd, Teflon, and firefighting foam. The risk to human health is "unknown" but exposure has been linked to various types of cancer, developmental issues, and preeclampsia in laboratory animals.

June 20, 2018 ATSDR Toxicological Profile for Perfluoroalkyls

Municipalities across the country have been demanding that government agencies expedite toxicological reports for this dangerous class of contaminants. Wilmington, North Carolina and several Michigan municipalities are just some of the locations that have been severely impacted by perfluoroalkyl contamination. Unfortunately, GenX, the most popular PFAS was not included in this particular toxicity study. This toxicological profile included provisional Minimal Risk Levels for both PFOA and PFOS. A Minimal Risk Level (MRL) is a non-enforceable standard, similar to an EPA health advisory level. The Agency for Toxic Substances and Disease Registry recommended reducing EPA’s non-enforceable health advisory from 70 parts per trillion to 20 parts per trillion for drinking water. This means municipalities across the country may be in exceedance with this new health recommendation, so people should stay current with public notices in their area.

Are Perfluoroalkyls Now Regulated? 

It’s important to note that this toxicity study does not mean that PFOA and PFOS contaminants are now regulated. The Agency for Toxic Substances and Disease Registry can only make recommendations and provide scientific data regarding this class of contaminants. It’s now up to regulatory agencies to comb through these data and make decisions to ensure that public health is protected. The regulatory process in this country, especially for toxic substances, can take upwards of decades. A regulation proposed by EPA or CDC could take years to draft and even longer before it’s enforceable.

Our Water Nerds are working around the clock to help make sense of this 852 page document. We’ll be reviewing the document and providing information on our Youtube, Facebook and Twitter accounts. Make sure to subscribe and follow Water Nerd TV on Facebook to stay up to date!

Analies Dyjak  |  Policy Nerd

Spring and summer are typically the seasons when algal blooms are most prevalent. When water temperatures rise and are accompanied by increased sunlight, it allows for higher rates of photosynthesis. This increased aquatic plant life can often lead to impairments in your drinking water. Here’s everything you need to know about algal blooms, cyanotoxins, and how to ensure your water is safe to drink.

What are Cyanotoxins?

Cyanobacteria naturally occurs in surface water. After an influx of nutrients or a sudden increase in water temperature, cyanobacteria can create Harmful Algal Blooms or HABs. HABs can then produce cyanotoxins, which are harmful to humans and the environment. Microcystins are the most widespread cyanotoxin in the United States, the most toxic being Microcystin-LR. Cyanotoxins are not currently federally regulated but the World Health Organization has provided an advisory level of 1 part per million for Microcystin-LR. Algal blooms and cyanotoxin production are extremely susceptible to changes in the surrounding environment. Toxicity levels can change within a matter of hours, making detection very difficult.

What are the Health Effects of Cyanotoxins in Drinking Water?

Acute exposure to cyanotoxins in drinking water can result in fevers, headaches, joint pain, stomach cramps and mouth ulcers and in severe cases, seizures, liver failure, and respiratory arrest. Studies have also found that long term exposure of low levels to microcystins can promote tumor growth, especially in the liver.

What Increases Levels of Cyanobacteria?

Anthropogenic factors are the predominant reason for an increased frequency and magnitude of cyanotoxin events. Nutrient loading from agricultural practices can cause algal blooms in both fresh and marine water, which also deoxygenates water systems.

How Do Harmful Algal Blooms Affect Water Treatment Facilities?

Municipal water treatment facilities generally do a good job of filtering out algae and cyanobacteria. They face problems when a large influx of algae clogs the filtration media. This can be costly to mitigate and challenging for municipalities if they lack proper equipment. Because cyanotoxins are not regulated, there’s a bit of a grey area as to whether municipalities are obligated to be looking for these contaminants. 

As always, we encourage you to take advantage of Hydroviv's "Help No Matter What" technical support policy, where we answer questions related to cyanotoxins, drinking water and water filtration. Drop us a line at hello@hydroviv.com.