The science of safer chemical ingredients

By Andrew Wineke, communications manager, Hazardous Waste and Toxics Reduction

Earlier this week, we told you about Washington’s progress in fighting copper pollution by working with brake manufacturers to cut copper in vehicle brake pads and shoes. Copper is toxic to salmon and other aquatic species, and brakes are a major source for the copper getting into our streams, rivers, lakes and Puget Sound.

Washington’s push has already reduced copper content in brakes by 25 percent since 2011. After seeing the good news, however, an astute reader asked, “Brake manufacturers replaced asbestos with copper – what’s replacing copper?”

And that’s a great question.

Asbestos is a mineral that was widely used for decades because of its ability to resist heat and fire. Widely used, that is, until it became clear that asbestos exposure could cause lung cancer and other serious health problems.

Replacing one toxic chemical with another is called a “regrettable substitution.” Sometimes, switching from a toxic chemical to a somewhat less-toxic substitute is the best option available.

Ideally, we can find alternatives that do not pose a threat to human health or the environment. At Ecology, we work with industry to tackle this challenge in several ways:

• First, we offer training and technical assistance in conducting chemical hazard assessments – these are rigorous comparisons that allow us to show we’ve looked at the full range of potential effects of a chemical. 
• We also work with industry on much broader reviews called alternatives assessments, which compare not only the toxicity of chemical ingredients, but also their cost, availability and performance.
• Lastly, we are partnering with industry and academic researchers to develop the science of green chemistry, which is the design of chemicals and processes so that they are safer, healthier and more sustainable. Green chemistry prevents pollution at its source by creating chemicals that are not toxic. 

 So now, back to the original question – how do we know we’re not repeating history, and that the minerals or compounds replacing copper won’t turn out to be harmful somehow in the future? We put the question to Ian Wesley, Ecology’s Better Brakes coordinator. Here’s what he told us:

“You’re correct that copper was introduced, in part, to replace asbestos in brake pads. Manufacturers have told us that they are using a number of strategies in reducing copper content.

They are using more ceramics, synthetic aramid fibers (like Kevlar), carbon, and other less-hazardous materials. Manufacturers are keenly aware of the dangers of regrettable substitution.

This is the second time in the 30 years they have had to completely reformulate their products. Many manufacturers are doing comprehensive toxicological screenings on the materials they use.

Manufacturers are also required to report on the content of nickel, zinc, and antimony in their products under the Better Brakes Law. Like copper, these metals are toxic to aquatic life and we are monitoring the amount of these metals released from brake products.” 

 At Ecology, we know that getting toxic chemicals out of the products we use is extremely important. Jumping from one toxic chemical to another, though, isn’t a smart investment. We’re doing everything we can to find the safest alternatives available.