Just a quick preface to this post. As a hydrologist, I am interested in all things water. Surface, sub-surface, fresh, salt, fast, slow…all of it. I am also interested in, and have been involved professionally with, water quality for my entire career. You really cannot separate the two. I, however, am not a chemist, nor do I claim to be. Nevertheless, as one who understands water quality regulations, point and non-point source pollution issues, and how all of this works regarding drinking water, waste water, stormwater, etc – questions about local water quality issues land in my lap. Of course, I have a personal interest, but mostly, I want people I know and care about to understand and proceed with knowledge.

So, the question of the day (week, month, year…) has been “what is this I hear about contaminants (toxins) being identified in our (local) drinking water?” Related questions:
- Why are there NO regulations on these substances if they are suspected or known to harm people?
- When will Maximum Contaminant Levels (MCL) be set by the EPA, so that there will be enforceable regulations?
- What are these chemicals doing to people, pets, and wildlife (when found in untreated surface waters)?
All excellent questions. Not many easy answers, but we can certainly try to clear up some of the confusion. One thing we cannot do is completely allay fears, as the presence of these contaminants should evoke a level of fear and concern. Your eyes should be wide-open to what you and your family are ingesting. Pay attention. Your health depends on it.

Currently there are over 90 contaminants regulated federally by the EPA related to Drinking Water, with Maximum Contaminant Levels (MCLs) determined. The MCLs allow for samples from water supplies/water treatment facilities to be monitored to make sure they meet the regulations set forth by the EPA’s Safe Drinking Water Standards. A list of these can be found here. A quick glance indicates a few things: 1) not all chemicals that we are are aware of as harmful are included in this list, and 2) the list is not exhaustive in its descriptions of the potential diseases and/or conditions that can result from exposure.
There is also this other list. It’s called the Contaminate Candidate List. Version 5 of this list is currently being developed. Version 4 was released in 2016. Per the EPA website:
The Final CCL 4 includes 97 chemicals or chemical groups and 12 microbial contaminants. The list includes, among others, chemicals used in commerce, pesticides, biological toxins, disinfection byproducts, pharmaceuticals and waterborne pathogens. These lists can be read by selecting the links below.
Final CCL 4 Chemical Contaminants List
This list is what is being considered for regulation…some of the names on this list have been on previous versions too, with no regulatory limit or MCL determined. Version 4 of the list (and most certainly Version 5 will follow suit) includes some of the Contaminants of Concern in our small town: PFOA, PFOS, and 1,4-Dioxane. Note the list does not say PFAS – which is the broader class of chemical compounds that PFOA and PFOS belong too. In an effort to learn more about where these compounds are used and how they might be entering our environment in excessive levels, per the EPA website:
PFAS can be found in:
Food packaged in PFAS-containing materials, processed with equipment that used PFAS, or grown in PFAS-contaminated soil or water.
Commercial household products, including stain- and water-repellent fabrics, nonstick products (e.g., Teflon), polishes, waxes, paints, cleaning products, and fire-fighting foams (a major source of groundwater contamination at airports and military bases where firefighting training occurs).
Workplace, including production facilities or industries (e.g., chrome plating, electronics manufacturing or oil recovery) that use PFAS.
Drinking water, typically localized and associated with a specific facility (e.g., manufacturer, landfill, wastewater treatment plant, firefighter training facility).
Living organisms, including fish, animals and humans, where PFAS have the ability to build up and persist over time.

So development of this Contaminant Candidate List is an ongoing effort by the EPA to determine what they should be reviewing/researching, and whether or not it warrants regulation via having a maximum acceptable amount (MCL) developed and then enforced per the Safe Drinking Water Act. The fact that a MCL has not been generated for these ~ 100 chemical/microbial contaminants does NOT mean they are safe. It simply means there is no enforceable limit that has to be met for drinking water standards. Important note here: this means while these contaminants may be present (at alarmingly high levels in some cases) a municipality (or other water supply provider) is still considered in compliance – because there is no related level to enforce. This is a bad situation.
For reference locally: PFOS/PFOA were found in the Haw River in high levels (far exceeding the EPA’s Health Advisory Level of 70 parts per trillion) as far back as 2007 in a research effort led by the EPA. The levels measured at that time in the Haw, near Pittsboro, were over 900 ppt. Over 10x the “acceptable levels”. Fast forward to 2013, when researchers from NC State, looking for other pollutants, detected high PFAS levels at 57 out of the 127 sampling events. Now, here we are in 2019, and a group of researchers through Duke University are studying effects of exposure to these contaminants. Multiple sampling events have continued to reveal high levels in the river and in the finished (treated) drinking water. The North Carolina Department of Environmental Quality, Division of Water Resources ordered additional monitoring, as detailed here:
In an effort to assess the levels of these contaminants throughout the Cape Fear and to assist DWR in developing a management strategy to address and reduce levels of these emerging contaminants, publicly owned treatment works with approved Pretreatment Programs in the Cape Fear River Basin will be required to perform investigative monitoring at the treatment plant for 1,4-dioxane and total PFAS monthly for three consecutive months starting in July 2019.
As a former researcher for the State, I can appreciate this want and need to collect as much data as possible. In the meantime however, we may want to err on the side of caution and follow the lead set by other States. Per an article from March of this year, “At least seven states have policies or have indicated they are pursuing policies stricter than EPA’s current health advisory of 70 parts per trillion (ppt) for PFOA and PFOS. They include Alaska, California, Minnesota, New Hampshire, New Jersey, New York and Vermont.” Many of these states have limits much lower than 70 ppt, even down to 13 ppt. According to Philippe Grandjean, Adjunct Professor of Environmental Health at Harvard, the safe standard should be set at 0.1 ppt, 700 times lower than what the EPA currently states as “safe”. He details siginifcant health effects observed during various studies, some are listed here.
Oddly enough, when I wrote about this months ago, related to GenX in the Wilmington area, I had no idea it would be knocking on our door in this way. I have family that live near Wilmington and I was alarmed at what was taking place…the GenX contamination has infiltrated not only the river where it was knowingly dumped as insufficiently treated industrial wastewater, but is also being found in the groundwater, soil, and air. In their case, the press helped get people’s attention and the State and local entities have been cracking down on this known point source – Chemours. With no single bad actor on the Haw, that has been identified at this time, the struggle is more diffuse and has gained seemingly little traction over the past 12 years.
Here’s a “fun fact” about Chemours. They are an offshoot of Dupont. Created to re-invent the Teflon required chemicals (PFASs) that had cost them huge sums of money in settlements that came out the lawsuits from Parkersburg, WV where the dumping of PFASs as industrial waste, and exposure of employees during manufacturing, created countless cases of terminal cancer, birth defects, and other illness. According to the documentary, the creation of this separate entity shields DuPont from the lawsuits which may follow in the future due to effects of exposure to contaminants such as GenX…you can learn all about the West Virginia events in the documentary The Devil We Know. Side note: be ready to clean out your cupboards after you watch it. Additional information regarding the PFOA related lawsuits in WV and Ohio is here.
To summarize where we are along the Haw River with this situation:
- Local University researchers are completing grant funded studies on the impacts of exposure to these chemicals and the State has funded the PFAST Network to study sources of and effects of exposure to PFAS
- No regulatory limits exist for these chemical compounds, so enforcement of “safe” levels is not currently possible. This is up to the EPA. Reach out to Federal Representatives and Senators and tell them this matters to you!
- The huge question of source(s) hinders the ability to reduce levels being found.
- Financial burden for higher levels of water treatment (i.e. reverse osmosis, activated carbon) fall to the localities and may be cost prohibitive…this is the only measure to take to protect citizens until sources are properly identified and levels reduced in the source water body. Residents may employ this technology at home as well.
- The State could enact their own limits, as the EPA, while stating a commitment to the issue has not made good on their promise to set enforceable limits.
One thing I would like to emphasize, is that PFAS’s should be be managed and regulated as a class and not one by one. This has been the method used for skirting around calling them ALL harmful. They are. Currently, as noted before, only two (PFOA and PFOS) appear on the Contaminant Candidate List. At this rate, new ones will simply replace those that end up regulated, if they ever are, and we will be spinning our wheels. This map helps illustrate how wide-spread of an issue we are dealing with here. Note it is over a year old.

“The updated map shows that PFAS contamination is truly a nationwide problem, impacting millions of Americans in hundreds of communities,” said Phil Brown, a professor of sociology and health sciences at Northeastern University and director of the Social Science Environmental Health Research Institute. “Leaders in many communities and states are doing great work to raise awareness about PFAS and push for cleanup, but this is a national crisis demanding national action. The EPA should act more quickly to evaluate all PFAS chemicals and restrict their use, and polluting industries should be held responsible.”
I encourage local NC residents to push for more action from the State, with creation of their own Safe Limits, protect yourself with the best filtration you can manage, and stay informed!
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