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PFAS and groundwater

November 26, 2024 By EarthWise Leave a Comment

Per- and polyfluoroalkyl chemicals, more commonly known as PFAS, are a family of human-made chemicals that have been manufactured and used in a variety of industries since the 1940s. They provide water-resistance, oil-resistance, dirt-resistance, and corrosion-resistance to a wide range of products, including food wrappers and packaging, clothing, dental floss, nonstick cookware, textiles, and electronics.

Exposure to PFAS has been linked to birth defects, thyroid disease, liver disease, kidney disease, and cancer. These chemicals do not break down in the environment and therefore, over time, become concentrated in plants, animals, and people.

According to a new first-of-its kind study by scientists at the U.S. Geological Survey, more than 20% of the U.S. population could be drinking groundwater contaminated with PFAS. The study, which was recently published in the journal Science, found that those living in the Eastern U.S. are particularly likely to be exposed.

The study is the first to report national estimates of PFAS in untreated groundwater that supplies drinking water to private and public wells. The USGS research also provides the first estimate of the total number of Americans – anywhere from 71 to 95 million – who might be exposed to this contamination.

The researchers note that their estimates merely measure the existence of PFAS – before the water has undergone any treatment or filtering – meaning that, while they may be present, they may be at very low levels.

To find a link to the detailed USGS map showing the probability of PFAS groundwater contamination in your region, visit our website: EarthWiseRadio.org.

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PFAS in US Groundwater Interactive Dashboard

Predictions of groundwater PFAS occurrence at drinking water supply depths in the United States

Photo, posted January 12, 2008, courtesy of Andrew Kraker via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Sponging up a river

March 20, 2024 By EarthWise Leave a Comment

During the first week of February, an atmospheric river dumped enormous amounts of rain on Southern California. Over the course of four days, Los Angeles received 9 inches of rain. The average annual rainfall in the city is only 14 inches.

But Los Angeles was not the site of a flooding disaster because the city has spent years preparing for this type of deluge by becoming a “sponge city.” By installing lots of green spaces and shallow basins with porous soil, Los Angeles was able to soak up 8.6 billion gallons of water during the storm, enough to meet the water needs of 100,000 people for a year.

Cities covered with impermeable concrete sidewalks and paved areas make storm-related flooding worse because they are unable to absorb water. Instead, the water flows into drains and overwhelms infrastructure.

Natural materials like dirt and plants take in water from storms and can filter it into underground aquifer that cities can then tap into, especially during droughts. Adding green spaces to cities has many other benefits beyond the ability to absorb large amounts of rainwater.

The so-called sponge-city movement is catching on in many other places. Philadelphia is revamping its water systems in a 25-year project that includes green spaces to absorb stormwater runoff. In China, the government has spent more than a decade adding spongy elements to dozens of cities around the country.

Sponge cities are part of a broader effort to combine modern engineering techniques with natural systems. This is known as green-gray infrastructure. Nature knows what it is doing when it comes to flood control as well as to pollution control.

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‘Spongy’ LA Soaked Up Tons of Water From Atmospheric River

Photo, posted December 28, 2011, courtesy of Ron Reiring via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Tracking down PFAS toxins

December 5, 2023 By EarthWise Leave a Comment

PFAS – per- and polyfluoralkyl substances – are a group of organic compounds that have been extensively used to provide water-, oil-, and dirt-resistance to a wide range of products ranging from non-stick pans, clothing, and packaging to paint, car polish, and fire-suppressant foam. Exposure to specific PFAS compounds is associated with multiple adverse health effects, including altered immune and thyroid function, liver disease, kidney disease, poor reproductive and developmental outcomes, and cancer. PFAS compounds do not break down in the environment and therefore, over time, become concentrated in plants, animals, and people.

Government agencies such as the EPA in this country and the EU have set strict limits for allowable levels of PFAS in drinking water. Testing water for the trace amounts of PFAS that constitute the limits is time-consuming and expensive and requires complex equipment and experienced personnel.

Researchers at MIT have now introduced a technique for making a portable, inexpensive test that can easily and selectively detect PFAS in water samples. The test makes use of a special polymer containing fluorinated dye molecules that cause the polymer to fluoresce red. If PFAS are present in the sample, they enter the polymer and displace the dye molecules and switches off the red fluorescence.

The new technique is suitable for on-site detection in highly contaminated regions. Detecting smaller concentrations can be achieved with sufficient precision after pre-concentrating the samples using the process of solid-phase extraction.

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Web Links

Tracking down Environmental Toxins

Photo, posted October 16, 2021, courtesy of Nenad Stojkovic via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Air Pollution And Diabetes

August 9, 2018 By EarthWise 3 Comments

Air pollution is deadly. Studies have found that fine particulate matter, such as airborne pieces of dust, dirt, smoke, soot, and other microscopic particles can enter our lungs and bloodstream, contributing to major health conditions such as heart disease, stroke, cancer, and kidney disease.