Removing Toxic Fluorinated Chemicals From Your Home’s Tap Water
By EWG Science Team
The family of fluorinated compounds known as PFAS chemicals includes more than 4,700 chemicals—some linked to cancer, thyroid disease, weakened immunity and developmental defects, and others whose health effects are unknown. One thing's for sure: You don't want them in your body.
Drinking water is one of the most common sources of exposure. PFAS chemicals could contaminate the drinking water for 110 million Americans nationwide. The Environmental Working Groups's (EWG) interactive map shows areas of known contamination. If you know or suspect these chemicals are in your tap water, the best way to protect yourself is by installing an in-home water filter. But which kind?
Based on information from state health agencies, testing labs, scientific researchers and water filter companies, the most effective choice for in-home treatment of PFAS-tainted tap water is a reverse osmosis filter, followed by an activated carbon filter—a slightly lower-cost option.
But many questions remain unanswered. More research is urgently needed to better understand how to ensure removal of the many types of PFAS compounds. To help with your choice, below are details of what is currently known.
Disclaimer: EWG is not recommending any specific brand of filter and cannot guarantee that a filter's performance will match the results reported below.
States Leading Response to PFAS Contamination Crisis
The U.S. Environmental Protection Agency (EPA) has set a health advisory level for the two most-studied PFAS compounds in drinking water—PFOA, formerly used to make DuPont's Teflon, and PFOS, formerly an ingredient in 3M's Scotchgard. The advisory level is 70 parts per trillion, or ppt, for the two chemicals combined. But the best and most current scientific research says that's much too high, and the EPA's advisory level is not legally enforceable.
That's why some states with extensive PFAS drinking water contamination are taking steps to set more health-protective limits or advisory levels. For example, New Jersey has set a legal limit of 13 ppt for perfluorononanoic acid, or PFNA, and proposed enforceable limits of 14 ppt for PFOA and 13 ppt for both PFOS. Other states such as Washington, Michigan, and North Carolina are conducting additional testing to further evaluate the extent of contamination in drinking water.
Some of these states have issued recommendations for water filters to remove PFOA and PFOS, including:
Guidance and factsheet documents from these states recommend two types of filters for removing PFAS chemicals: activated carbon and reverse osmosis. The states provide information on the pluses and minuses of the two types, and tips on how to maintain them to ensure effective filtering. They also compare the two types of filter installations: "point of use," which are installed under the kitchen sink or in the refrigerator, and "point of entry," which treat the water for the whole house.
In communities with the worst contamination, such as in Minnesota or Michigan, whole-house filtration is often used. It is effective, but expensive in comparison to point-of-use filtration and may not be necessary in most cases. Further, since whole-house systems also remove chlorine, they may introduce additional risks of harmful bacterial growth in plumbing.
Filters Certified for PFAS Chemical Removal
NSF International, a testing and certification company, developed a certification standard for removal of PFOS and PFOA in 2016. The certification requires that the filter reduce these two chemicals only to EPA's health advisory level of 70 ppt. Currently, 71 products from seven manufacturers are certified to meet this standard.
However, drinking water can contain other PFAS chemicals, sometimes at higher levels than PFOS and PFOA. PFOS and PFOA, which are now banned, are called 'long-chain' compounds because they have eight carbon atoms, while the chemicals that have replaced them are called 'short-chain' compounds because they have fewer carbon atoms. While similar, these so-called "next-generation" compounds have different molecular structures, and the effectiveness of filters certified for PFOS and PFOA for removal of replacement PFAS chemicals is unknown.
Filter Testing by State Agencies
In 2007, the Minnesota Department of Health commissioned testing of home water filters to determine their efficacy in removing PFAS. Six activated carbon filters and eight reverse osmosis filter types were tested. The tests determined that four of the six carbon filters and seven of the eight reverse osmosis filters provided sufficient reduction of PFAS chemicals. In field testing, four activated carbon devices and seven reverse osmosis systems, all equipped in tandem with activated carbon filters, removed PFOA, PFOS and PFBA to the detection limit of 50 ppt.
The study noted that for the carbon filters, the effectiveness of removal of PFOA, PFOS and another chemical, PFBA, decreased over operating life in five of the six filters tested in laboratory conditions. That means that users will have to replace the filters on the recommended schedule to ensure effective filtration of PFAS chemicals.
In 2017, Minnesota released the results of a study for a faucet-mounted carbon filter made by PUR. The filter was tested for seven PFAS chemicals typically seen in groundwater in Washington County in Minnesota. The state concluded that this low-cost filter could be used to effectively reduce PFAS contamination. Six of seven contaminants including PFOA and PFOS were removed below the reporting limits of 5 and 10 ppt, respectively, achieved in the 2017 study. In contrast, levels of the shorter chain PFBA were only reduced by 75 percent.
Filter Testing by Academic Institutions
Last year, Knappe told the Star News of Wilmington, N.C. that an under-sink reverse osmosis filter was probably the best choice for home treatment. He said it's not only effective, but its continued effectiveness can be easily verified with an electrical conductivity tester, an inexpensive tool that people can use at home.
Detailed testing results were publicly presented in 2017 for four under-sink reverse osmosis filters and one whole-house activated carbon filter. These filters that were tested for removal of a dozen PFAS chemicals, including both long-chain and short-chain compounds.
Three out of four reverse osmosis filters reduced the long-chain compounds to below 10 ppt, with the other filter reducing them to a slightly higher level. The four reverse osmosis systems also removed between 95 and 99 percent of short-chain compounds.
One whole-house activated charcoal filter from Aquasana was tested. It provided no reduction of PFAS levels. In contrast, an activated carbon filter made by Hydroviv delivered results similar to the reverse osmosis filters.
EWG Contacted Water Filter Companies
EWG surveyed 51 water filter companies to find out about their filters' capabilities to remove PFAS. We heard back from 14 companies, but only four of them verified that their filters remove any PFAS chemicals.
Only Berkey provided EWG with test data for their carbon filters, which reported removal of nine PFAS chemicals, including PFOA and PFOS, all below the detection limit of 2 ppt. However, only 25 gallons of water were filtered, instead of the recommended 6,000 gallons to measure lifetime efficacy. Aqua Systems and Triple Clear stated that removal for their products was only to the EPA advisory levels and Crystal Quest reported that removal was variable.
Reverse Osmosis Filters vs. Activated Carbon Filters
In general, reverse osmosis systems more consistently removed PFAS compared to activated carbon systems.
Most reverse osmosis systems also have the benefit of an additional activated carbon filtration stage included in the system. Reverse osmosis systems remove a wider range of other contaminants from drinking water and their effectiveness can be tested at home using an electrical conductivity meter. But activated carbon filter systems are significantly less expensive than reverse osmosis systems. Carbon filters must be changed on schedule as they will lose their effectiveness over time.
- Check out EWG's interactive PFAS map to see if your drinking water has high levels of PFAS chemicals or if there is a contamination site near your community.
- If you live in an area with contamination, contact your local health department for current information.
- If you have a private well and suspect PFAS contamination, consult your state health department about having your well tested.
- The best bet to filter PFAS chemicals out of your water is an in-home reverse osmosis filter under your sink or at your tap. To ensure that the reverse osmosis filter is working, use an inexpensive conductivity meter. These filter systems remove ions and total dissolved solids in addition to other contaminants, and a low conductivity reading for the filtered water indicates that the filter is overall effective.
- You can also consider an activated carbon filter that will most often provide effective removal. Results have been inconsistent and the filters become less effective with time. If possible, choose a filter that has been tested for PFOS, PFOA and additional PFAS chemicals that may be present in your water.
EcoWatch Daily Newsletter
By Zahida Sherman
Cooking has always intimidated me. As a child, I would anxiously peer into the kitchen as my mother prepared Christmas dinner for our family.
Falling in Love With Food All Over Again<p>Slowly, through my most intimate relationships with friends and partners, I began to see the beauty — and rewards — of cooking.</p><p>I got tired of giving in to defeat and always bringing chips or paper products to social gatherings. I started asking my mom to send me her Christmas and Thanksgiving recipes. I even volunteered to host Thanksgiving dinner at my place.</p><p>Each time I heard my loved ones sing the praises of the foods I prepared for them, I felt a tinge more confident that I could carry out our traditions my way.</p><p>In reaching out to other relatives for their favorite recipes, I learned that they had a little help of their own. They didn't rely solely on their ancestral cooking instincts. They turned to Black chefs for guidance.</p><p>These 7 cookbooks by Black chefs have inspired my family and fed us in nutrients, joy, and spiritual sustenance. They're also helping me overcome my personal fears of cooking.</p>
Get CookingWhether you're in recovery from cooking fears like me, or are just looking to expand your culinary confidence with dishes honoring Black heritage, these Black chefs are here to support you on your journey.Turn on some music, give yourself permission to make mistakes, and throw down for yourself or your loved ones. Glorious flavors await you.
- 18 Cookbooks for Building a Diverse and Just Food System ... ›
- 19 Individuals and Groups Building Stronger Black Communities ... ›
- 8 Cookbooks We're Reading This Fall - EcoWatch ›
The Food and Drug Administration (FDA) has expanded its list of potentially toxic hand sanitizers to avoid because they could be contaminated with methanol.
- Here's How to Clean Your Groceries During the COVID-19 Outbreak ... ›
- Why Hand-Washing Really Is as Important as Doctors Say - EcoWatch ›
- If You're Worried About the New Coronavirus, Here's How to Protect ... ›
- Vodka Won't Protect You From Coronavirus, and 4 Other Things to ... ›
By Tara Lohan
The conclusion to decades of work to remove a dam on the Middle Fork Nooksack River east of Bellingham, Washington began with a bang yesterday as crews breached the dam with a carefully planned detonation. This explosive denouement is also a beginning.
The History<p>The Middle Fork Nooksack drains glacier-fed headwater streams that run off the icy summit of 10,778-foot Mt. Baker. The Middle Fork joins the North Fork and then the mainstem of the Nooksack River, which travels to Bellingham Bay and Puget Sound. The entire Nooksack watershed stretches 830 square miles across Washington and into British Columbia.</p>
A Plan Comes Together<p>The Middle Fork dam is not a pool dam built for water storage. Much of the time, water flows over the top until dam operators drop a floodgate to divert water to new locations. That water travels about 14 miles through tunnel and pipeline to Mirror Lake, then Anderson Creek, and to Lake Whatcom before finally being delivered to residents' taps.</p><p>Before removing the dam, engineers had to move the water intake 700 feet upstream and situate it at an elevation that still enabled city water withdrawals throughout the year, regardless of flow conditions.</p><p>They also needed to make sure that the rushing water didn't sweep up fish and accidentally send them through the water-supply system.</p><p>"The solution required a fairly complex design in the intake structure, including a fish exit pipe out of that structure to put fish back into the river in a way that meets current environmental permit standards," explains LaCroix.</p>
Project layout for the removal of the Middle Fork Nooksack diversion dam and rebuilding of water intake. City of Bellingham<p>Despite the cost and the work, she says, being able to continue to meet their municipal water obligations while opening up habitat for threatened species has been a win-win.</p><p>"I think there's a lot of benefits to having a dam removal versus fish passage — the main one being that you get a free-flowing river that can be a dynamic ecosystem and change over time," she says. "A static fish ladder just can't provide that same level of ecosystem benefit."</p>
Restoration Success<p>Despite local authorities' championing dam removal on the Middle Fork, the project has largely flown under the radar, overshadowed in the Pacific Northwest by heated discussions about a much larger potential project — removing <a href="https://www.seattletimes.com/seattle-news/feds-reject-removal-of-4-snake-river-dams-in-key-report/" target="_blank">four federal hydroelectric dams on the lower Snake River</a>, a major tributary of the Columbia River.</p><p>Proponents of dam removal there see it as the best chance for recovering threatened salmon populations, including Chinook, which could help starving Southern Resident killer whales. Those dams also provide irrigation water, barge navigation and hydropower, so there's been more pushback against removal efforts.</p><p>Previous dam removals around the country, however, have proved successful at aiding fish recovery and river restoration.</p><p>Most notably the 1999 demolition of <a href="https://therevelator.org/edwards-dam-removal/" target="_blank">Edwards Dam on Maine's Kennebec River</a> restored the annual run of alewives, a type of herring essential to the food web. The fish run has gone from zero to 5 million in the two decades since dam removal. Blueback herring, striped bass, sturgeon and shad have also extended their reach. And the resurgence has brought back osprey, bald eagles and other wildlife, too.</p><p>The overwhelming success of river restoration on the Kennebec helped to spur a nationwide dam removal movement that's now seen 1,200 dams come down since 1999. Last year a record <a href="https://www.americanrivers.org/conservation-resource/a-record-26-states-removed-dams-in-2019/" target="_blank">90 dams</a> were removed in 26 states, including <a href="https://therevelator.org/cleveland-forest-dam-removal/" target="_blank">20 dams in California's Cleveland National Forest</a>.</p>
Spider excavators remove on dam on San Juan Creek in California's Cleveland National Forest. Julie Donnell, USFS<p>The results have been seen in the Pacific Northwest, as well, which boasts the largest dam removal thus far in the country. In 2011 and 2014, the demolition of <a href="https://therevelator.org/elwha-dam-removal/" target="_blank">two dams</a> on Elwha River, which runs through Washington's Olympic National Park, opened up 70 miles of habitat that had been blocked for a century. Scientists have started seeing all five species of salmon native to the river coming back, particularly Chinook and coho. Bull trout, they've observed, have increased in size since the dams were removal.</p>
Benefits on the Middle Fork Nooksack<p>McEwan hopes to see a similar outcome on the Middle Fork.</p><p>Like the Elwha the Middle Fork Nooksack is a relatively pristine river with little development, and dam removal is expected to provide a big boost to fish. The additional miles of spawning habitat are important, but so is the temperature of that water.</p><p>The dam removal will open access to cold upstream waters, which are ideal for salmon and getting harder to come by as climate change warms waters and reduces mountain runoff.</p><p>"This is really great for the climate change resiliency for these species," says McEwan.</p><p>Steelhead will get back 45% of their historic habitat in the river, and scientists expect Chinook populations to increase in abundance by 31%.</p><p>That <em>could</em> help Southern Resident killer whales.</p><p>"When you get to the ocean, it's a little bit of a black box in terms of what you can model and say definitively is going to help, but more fish is better for orcas," McEwan says.</p><p>Upstream habitat will see benefits, too.</p><p>Oceangoing fish like salmon enrich their bodies with carbon and nitrogen while at sea. When they return to their natal rivers to spawn and die, the marine-derived nutrients they carry back upriver become important food and fertilizer for both riverine and terrestrial ecosystems — aiding everything from trees to birds to bears.</p><p>"Once the fish start making their way back, it will start changing the whole ecological system," says Delgado.</p><p><span></span>But any ecological benefit from salmon restoration, either in the ocean or the upper watershed, won't be immediate.<br></p><p>"The population of salmon on the Middle Fork is so low that we expect it's going to take quite a while to rebound," she says. "But the big picture is that what's good for salmon is good for the region — our history and our destiny are intricately intertwined."</p><p>After decades of work, that process of restoration has finally begun.</p>
- 4 Exciting Dam-Removal Projects to Watch - EcoWatch ›
- Jump-Starting the Dam Removal Movement in the U.S. - EcoWatch ›
- Boom: Removing 81 Dams Is Transforming This California Watershed ›
- Sea Level Rise Is Speeding up Along Most of the U.S. Coast ... ›
- Protecting Mangroves Can Prevent Billions of Dollars in Global ... ›
- Flooding Risk for U.S. Homes: Millions More Are Vulnerable Than ... ›
- 300 Million People Worldwide Could Suffer Yearly Flooding by 2050 ... ›
- Sea Level Rise Could Put 2.4 Million U.S. Coastal Homes at Risk ... ›
By Katie Howell
A new tool called The Food Systems Dashboard aims to save decision makers time and energy by painting a complete picture of a country's food system. Created by the Johns Hopkins' Alliance for a Healthier World, the Global Alliance for Improved Nutrition (GAIN), and the U.N. Food and Agriculture Organization (FAO), the Dashboard compiles food systems data from over 35 sources and offers it as a public good.
By Manuela Callari
It can grow to a maximum of six inches (16 centimeters), change color depending on mood and habitat, and, like all seahorses, the White's seahorse male gestates its young. But this tiny snouted fish is under threat.
Building an Ocean Seahorse Destination<p>Seahorses are found in tropical and temperate coastal water worldwide, but are most abundant around Australia, China and the Philippines. </p><p>Trade in the tiny creatures is strictly regulated because of their use in traditional medicine, aquariums and their sale as dried curios. But because they are poor swimmers and cannot easily move elsewhere, habitat loss is a particular threat for these curious animals. </p><p>Seahorses wrap their tails around seagrass and corals to avoid being carried away on currents. They use the habitat to spawn and hide from predators such as crabs, while also feeding on riches of plankton and small crustaceans living in the reef.</p><p><span></span>Where corals aren't available, <a href="https://onlinelibrary.wiley.com/doi/abs/10.1002/aqc.1217" target="_blank">scientists</a> found seahorses taking up residence in fishing nets and old crab traps abandoned at the bottom of the ocean. </p>
Mixing With the Locals<p>Baby seahorse mortality is high in the wild because they are easily caught, so those bred in the protected environment of the aquarium weren't ready to be released into the wild until early May.</p><p>The team released 90 new arrivals into Sydney Harbor, placing some directly into the purpose-built hotels, and others onto a net that wild seahorses had already settled on.</p><p>Before setting them free, the researchers marked each young seahorse with a fluorescent tag with unique IDs inserted just beneath the skin to track how they get on in the different environments. </p><p>"The most exciting part was being able to put these animals into the wild and then go back a month later and still see them surviving and growing," said McCracken. </p><p>The seahorses will be old enough to mate and reproduce around October or November 2020. And researchers hope that by then, they will be able to breed with the wild population. </p>
Building a Global Seahorse Hotel Chain<p>With seahorses everywhere facing the loss of their coral reef homes, similar projects have sprung up in places like Greece and South Africa, home to the world's most endangered seahorse, the Knysna seahorse. </p><p>"The endangered South African seahorse is benefiting from something quite similar, even though it wasn't intentional," said Peter Teske, professor at the Department of Zoology, University of Johannesburg.</p><p>In the South African <a href="https://www.researchgate.net/publication/322649251_An_endangered_seahorse_selectively_chooses_an_artificial_structure" target="_blank">case</a>, seahorses have bedded down in "Reno mattresses" — wire cages filled with rocks — that were used to build a new marina. Researchers from NGO Knysna Basin Project found the structures acted as a refuge for the animals.<span></span></p><p><span></span>While Teske describes the seahorse hotels as "a positive news story" and a great way to create public awareness of conservation, he added that establishing artificial habitats in some areas will only prevent the extinction of local populations.</p><p>"For a complete recovery, it is necessary to give the natural habitat a chance to regenerate," said the seahorse expert. </p>
Underwater Mascot<p>In Australia, the researchers hope the project could provide an opportunity to raise awareness not only of the plight of the Sydney seahorses but the other animals with which it shares its ocean habitat.</p><p>The waters around Sydney and the east coast are rich in biodiversity and include several threatened species like the weedy seadragon — a relative of the seahorse — and the grey nurse shark. Like the seahorse, they're also under pressure from pollution, ocean traffic and habitat loss through storms and coastal construction. </p><p>"It's a good thing to get people's support and interest. The seahorses are a useful vehicle to get people concerned if the harbor is in trouble," said David Booth, professor of marine ecology at the University of Technology Sydney who is also working on the project. </p><p>The hotels have become an attraction for divers hoping to catch a glimpse of these small but near mythical creatures. </p><p>"Everyone loves seahorses," added Booth, "they are so popular." </p>
- 7 Amazing New Fish Species Discovered in 2017 - EcoWatch ›
- Millions of Seahorses Wind Up Dead on the Black Market for This ... ›
Presidential hopeful Joe Biden announced a $2 trillion plan Tuesday to boost American investment in clean energy and infrastructure.
- Green New Deal Champion AOC Will Serve on Biden Climate Panel ... ›
- Biden-Sanders Unity Task Forces Unveil Improved Climate Policy ... ›