Why Is a 50-Year-Old Problem Still Threatening Our Birds?
For years, I’ve been inspired by Rachel Carson and motivated to follow in her footsteps by highlighting and addressing the health effects of chemical exposures, but I didn’t think that I would ever be discussing issues that so closely mirror her own life’s work. More than fifty years have passed since she wrote her iconic book Silent Spring, yet because of our broken chemical regulatory system, we are still facing the same problems. A recently released study by the US Geological Survey (USGS) suggests that, just as in Carson’s time, synthetic chemicals in the environment are interfering with reproduction in bird populations.
In Silent Spring, released in 1962, Carson described the harmful effects of synthetic pesticides and cautioned us that the indiscriminate use of these compounds could lead to a world devoid of the sweet sounds of songbirds that usually mark the arrival of springtime. She focused in particular on DDT, a long-lived pesticide that builds up, or “bioaccumulates,” in the bodies of animals. Birds with high concentrations of DDT in their bodies produce weakened eggshells that often break before the hatching of the offspring. Carson warned that these chemicals threatened future generations of birds and other animals, including our own species.
They say history repeats itself, and the USGS study released this fall suggests this old adage is as true as ever. Scientists have found that certain chemicals used to make common consumer products, including nonstick cookware and water-resistant clothing, are reducing the reproductive success of tree swallows. Specifically, higher levels of chemicals known as perfluoroalkyl substances (PFASs) in tree swallow eggs were associated with a decreased chance of egg hatching.
A different chemical, but an eerily similar story.
So while we can applaud some successful battles to phase out particularly harmful chemicals (in the case of DDT, EDF played an important role in fighting for this ban), it seems like we are losing the war. One dangerous chemical is eliminated, but another problematic one crops up.
Furthermore, even after their production or use is banned, many toxic chemicals persist in the environment for long periods of time. Because of global concerns about exposures and effects on humans and wildlife, some members of the chemical family that are the subject of the recent USGS study have been or are being phased out of production. However, this study suggests that even chemicals no longer in use may still be interfering with ecosystem health today.
It’s not just about birds. It’s about us, too. As I highlighted in a previous post, PFASs (referred to in that post as “PFCs,” an alternative name for the same group of chemicals) are also associated with numerous adverse health effects in humans, including decreased male reproductive health.
The scale of the bigger problem here is such that we cannot succeed by working case-by-case to remove harmful chemicals from the market after widespread exposure. Instead, we need a system that ensures that all chemicals in use are safe.
That’s why EDF has been working for nearly 20 years to reform the Toxic Substances Control Act (TSCA). Passed in 1976, this outdated and ineffective law fails to protect Americans from potentially harmful chemicals used in their homes and workplaces.
EDF is now working to improve and pass a bipartisan Senate bill to reform TSCA. If the needed improvements can be made, it offers our best chance in decades to improve chemicals regulation and management in this country.
The alternative is to see the Silent Spring story of the 1960s repeat itself over and over again.
This article originally appeared on the EDF Voices blog and is reprinted with permission.
Photo Credit: Environmental Defense Fund