PFAS ‘forever chemicals’ are widespread and threaten human health – here’s a strategy for protecting the public



Firefighting foam left after a fire in Pennsylvania. These foams often contain PFAS chemicals that can contaminate water supplies.
Bastiaan Slabbers/NurPhoto via Getty Images

Carol Kwiatkowski, North Carolina State University

Like many inventions, the discovery of Teflon happened by accident. In 1938, chemists from Dupont (now Chemours) were studying refrigerant gases when, much to their surprise, one concoction solidified. Upon investigation, they found it was not only the slipperiest substance they’d ever seen – it was also noncorrosive and extremely stable and had a high melting point.

In 1954 the revolutionary “nonstick” Teflon pan was introduced. Since then, an entire class of human-made chemicals has evolved: per- and polyfluoroalkyl substances, better known as PFAS. There are upward of 6,000 of these chemicals. Many are used for stain-, grease- and waterproofing. PFAS are found in clothing, plastic, food packaging, electronics, personal care products, firefighting foams, medical devices and numerous other products.

But over time, evidence has slowly built that some commonly used PFAS are toxic and may cause cancer. It took 50 years to understand that the happy accident of Teflon’s discovery was, in fact, a train wreck.

As a public health analyst, I have studied the harm caused by these chemicals. I am one of hundreds of scientists who are calling for a comprehensive, effective plan to manage the entire class of PFAS to protect public health while safer alternatives are developed.

Typically, when the U.S. Environmental Protection Agency assesses chemicals for potential harm, it examines one substance at a time. That approach isn’t working for PFAS, given the sheer number of them and the fact that manufacturers commonly replace toxic substances with “regrettable substitutes” – similar, lesser-known chemicals that also threaten human health and the environment.

Graphic showing how PFAS moves from many sources into soil and water
As PFAS are produced and used, they can migrate into soil and water.
MI DEQ

Toxic chemicals

A class-action lawsuit brought this issue to national attention in 2005. Workers at a Parkersburg, West Virginia, DuPont plant joined with local residents to sue the company for releasing millions of pounds of one of these chemicals, known as PFOA, into the air and the Ohio River. Lawyers discovered that the company had known as far back as 1961 that PFOA could harm the liver.

The suit was ultimately settled in 2017 for US$670 million, after an eight-year study of tens of thousands of people who had been exposed. Based on multiple scientific studies, this review concluded that there was a probable link between exposure to PFOA and six categories of diseases: diagnosed high cholesterol, ulcerative colitis, thyroid disease, testicular cancer, kidney cancer and pregnancy-induced hypertension.

Over the past two decades, hundreds of peer-reviewed scientific papers have shown that many PFAS are not only toxic – they also don’t fully break down in the environment and have accumulated in the bodies of people and animals around the world. Some studies have detected PFAS in 99% of people tested. Others have found PFAS in wildlife, including polar bears, dolphins and seals.

Attorney Robert Billott describes suing Dupont for knowingly releasing millions of pounds of hazardous PFOA in Parkersburg, West Virginia.

Widespread and persistent

PFAS are often called “forever chemicals” because they don’t fully degrade. They move easily through air and water, can quickly travel long distances and accumulate in sediment, soil and plants. They have also been found in dust and food, including eggs, meat, milk, fish, fruits and vegetables.

In the bodies of humans and animals, PFAS concentrate in various organs, tissues and cells. The U.S. National Toxicology Program and Centers for Disease Control and Prevention have confirmed a long list of health risks, including immunotoxicity, testicular and kidney cancer, liver damage, decreased fertility and thyroid disease.

Children are even more vulnerable than adults because they can ingest more PFAS relative to their body weight from food and water and through the air. Children also put their hands in their mouths more often, and their metabolic and immune systems are less developed. Studies show that these chemicals harm children by causing kidney dysfunction, delayed puberty, asthma and altered immune function.

Researchers have also documented that PFAS exposure reduces the effectiveness of vaccines, which is particularly concerning amid the COVID-19 pandemic.

Regulation is lagging

PFAS have become so ubiquitous in the environment that health experts say it is probably impossible to completely prevent exposure. These substances are released throughout their life cycles, from chemical production to product use and disposal. Up to 80% of environmental pollution from common PFAS, such as PFOA, comes from production of fluoropolymers that use toxic PFAS as processing aids to make products like Teflon.

In 2009 the EPA established a health advisory level for PFOA in drinking water of 400 parts per trillion. Health advisories are not binding regulations – they are technical guidelines for state, local and tribal governments, which are primarily responsible for regulating public water systems.

In 2016 the agency dramatically lowered this recommendation to 70 parts per trillion. Some states have set far more protective levels – as low as 8 parts per trillion.

According to a recent estimate by the Environmental Working Group, a public health advocacy organization, up to 110 million Americans could be drinking PFAS-contaminated water. Even with the most advanced treatment processes, it is extremely difficult and costly to remove these chemicals from drinking water. And it’s impossible to clean up lakes, river systems or oceans. Nonetheless, PFAS are largely unregulated by the federal government, although they are gaining increased attention from Congress.

Water treatment tanks
Part of a filtration system designed to remove PFAS from drinking water, Horsham Water and Sewer Authority, Horsham, Pennsylvania.
Bastiaan Slabbers/NurPhoto via Getty Images

Reducing PFAS risks at the source

Given that PFAS pollution is so ubiquitous and hard to remove, many health experts assert that the only way to address it is by reducing PFAS production and use as much as possible.

Educational campaigns and consumer pressure are making a difference. Many forward-thinking companies, including grocers, clothing manufacturers and furniture stores, have removed PFAS from products they use and sell.

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State governments have also stepped in. California recently banned PFAS in firefighting foams. Maine and Washington have banned PFAS in food packaging. Other states are considering similar measures.

I am part of a group of scientists from universities, nonprofit organizations and government agencies in the U.S. and Europe that has argued for managing the entire class of PFAS chemicals as a group, instead of one by one. We also support an “essential uses” approach that would restrict their production and use only to products that are critical for health and proper functioning of society, such as medical devices and safety equipment. And we have recommended developing safer non-PFAS alternatives.

As the EPA acknowledges, there is an urgent need for innovative solutions to PFAS pollution. Guided by good science, I believe we can effectively manage PFAS to reduce further harm, while researchers find ways to clean up what has already been released.The Conversation

Carol Kwiatkowski, Adjunct Assistant Professor of Biological Sciences, North Carolina State University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The battle against bugs: it’s time to end chemical warfare



File 20190215 56220 4e8qzx.jpg?ixlib=rb 1.1
Does it really pay to spray?
Dmitry Syshchikov/Shutterstock

Lizzy Lowe, Macquarie University; Cameron Webb, University of Sydney; Manu Saunders, University of New England, and Tanya Latty, University of Sydney

Insects are important wildlife often overlooked in urban habitats. What we do notice are the cockroaches, ants and mosquitoes in and around our homes. All too often we reach for the insect spray.

But not all insects are pests – a wide variety of them help keep our cities healthy. They pollinate plants, feed other wildlife, recycle our rubbish, and eat other insect pests. Insects are vital to our well-being.

Unfortunately, like many other wild animals, insects are under threat. A recent study warned that 40% of the world’s insect species face the prospect of extinction, amid threats such as climate change, habitat loss, and humanity’s overenthusiastic use of synthetic chemicals.

Australians use large amounts of pesticides to tackle creepy crawlies in their homes and gardens. But our fondness for fly spray has potentially serious impacts on urban ecosystems and public health.

We need a more sustainable way to deal with urban insect pests. Our recently published article in the Journal of Pest Science outlines some of the ways to do it.

What’s wrong with pesticides anyway?

Since becoming publicly available in the 1950s, insect sprays have been a popular way to deal with cockroaches, flies, moths, and ants around the home and backyard, and are also widely used by local councils to keep pests at bay. But what may have been effective in the past won’t necessarily work in the future, or may have unintended consequences.

Many pests, such as mosquitoes, are now becoming resistant to commonly used products. In parts of the world affected by diseases such as dengue, this jeopardises our ability to control outbreaks.




Read more:
Chemical or natural: what’s the best way to repel mozzies?


Another, perhaps wider, problem is that indiscriminate use of insecticides can kill more than just pests. Many species on which we rely for keeping our backyard gardens, bushland, wetlands and parks healthy can become collateral damage. This includes predatory species that can themselves help keep pests under control. As pest species often reproduce faster than their predators (a pattern that’s likely to be reinforced by climate change), we can get trapped in a cycle in which pest numbers bounce back higher than ever.

Many wasps are predatory and specialise in eating insects that can be pests around the home.
Manu Saunders



Read more:
Five reasons not to spray the bugs in your garden this summer


How do we do things differently?

Fortunately, there are alternatives to chemical pest control that don’t harm your household or the environment. For centuries, sustainable agriculture systems have used environmentally friendly approaches, and city-dwellers can take a leaf from their books.

Integrated pest management is one such sustainable approach. It focuses on prevention rather than treatment, and uses environmentally friendly options such as biological control (using predators to eat pests) to safeguard crops. Chemical insecticides are used only as a last resort.

There are many other farming practices that support sustainable pest control; these focus on behavioural change such as keeping areas clean, or simple physical controls such as fly mesh or netting around fruit trees.

Adopting these methods for urban pest control isn’t necessarily straightforward. There might be local regulations on particular pest control activities, or simply a lack of knowledge about urban pest ecology.

For urgent pest situations, it may be more expensive and time-consuming to set up a biological control program than to arrange the spraying of an insecticide. Insecticides take effect immediately, whereas biological control takes longer to have an effect. Prevention, the cornerstone of integrated pest management, requires careful planning before pests become a nuisance.

The goal of integrated pest management is not to eliminate insect pests entirely, but rather to reduce their numbers to the point at which they no longer cause a problem. By this logic, chemical insecticides should only be used if the economic damage caused by the pests outweighs the cost of the chemicals. If you hate the idea of a single cockroach living anywhere nearby, this might require you to adjust your mindset.

What can I do at home?

Don’t give pests opportunities. Be mindful of how we produce and dispose of waste. Flies and cockroaches thrive in our rubbish, but they can be effectively managed by ensuring that food waste is stored in insect-proof containers, recycled, or properly disposed of. Don’t leave buckets of water around the backyard, as this invites mosquitoes to breed.

Don’t open your door to pests. Seal cracks and crevices in the outside of your house, and ensure there are screens on your doors and windows.

Support the animals that control insect pests – they’ll do the hard work for you! In particular, don’t be so quick to kill spiders and wasps, because they prey on pests in your home and garden.

Spiders like this leaf curler will happily eat a range of pests, including ants, around your home.
jim-mclean/flickr



Read more:
The secret agents protecting our crops and gardens


What can we do as a community?

Urban communities can learn a lot from sustainable farming. First, there needs to be better education and support provided to the public and policy makers. Workshops run by local councils and information sessions with local gardening groups are a great way to start.

We can also work together to help debunk the popular myth that most insects are damaging or unwanted pests. Reaching for the fly spray might be easy, but remember you may end up killing friends as well as foes.The Conversation

Lizzy Lowe, Postdoctoral researcher, Macquarie University; Cameron Webb, Clinical Lecturer and Principal Hospital Scientist, University of Sydney; Manu Saunders, Research fellow, University of New England, and Tanya Latty, Senior Lecturer, School of Life and Environmental Sciences, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.