OPINION: To Members of the Hingham Recreation Commission and Hingham Select Board

October 17, 2024 By Diana Zuckerman

It has come to my attention that Hingham officials have been misled about the safety of various playground surfaces.  My goal is to provide you with the scientific information that will help you determine what is best for the children and adults in your community.

As President of the National Center for Health Research, I am writing at the request of many of your constituents to share the information we have provided to Members of Congress, state and federal agencies, state and local legislators, parents, and others who want to ensure that our children are not exposed to dangerous chemicals and dangerously hot temperatures on playgrounds.

Our nonprofit think tank is located in Washington, D.C. Our scientists, physicians, and health experts conduct studies and scrutinize research. Our goal is to explain scientific and medical information that can be used to improve policies, programs, services, and products.

We understand that these issues are hotly debated, but some information is more accurate than others. For example, although PIP (poured in place) playground surfaces and playgrounds covered with colorful recycled rubber mulch are attractive and seem safe if children fall, it contains chemicals that are harmful to children and the environment.  The top layer of “virgin rubber” is somewhat safer than recycled tire mulch but has many of the same risks.  And the top layer cracks and wears off, resulting in children’s exposure to recycled tire mulch, which contains lead and other heavy metals and toxic chemicals. I’m sure you know that the American Academy of Pediatrics warns that no level of lead is safe. Lead dust has been found on the surface of these playgrounds, and that is especially unsafe because it will get on children’s hands and clothing, and they will breathe it in their mouth and lungs when they play. Small children put pieces of rubber mulch in their mouths, especially if it is an attractive color.

Although PIP seems to be a solid surface, the top layer of rubber will wear off after a few years (especially in places where children are most active, such as the bottom of a slide) and underneath the tire crumb will seem quite interesting to small children, who will play with it and put it in their mouth and pockets – sometimes even up their noses.

In the last few years, scientists have learned more about lead and PFAS in these playgrounds. Tire mulch has well-known risks, containing chemicals that have the potential to increase obesity; contribute to early puberty; cause attention problems such as ADHD; exacerbate asthma; and eventually cause cancer. Unfortunately, the virgin rubber surface itself has dangerous levels of lead, PFAS, and other toxic chemicals as well. PFAS are of particular concern because they enter the body and the environment as “forever chemicals,” which means that they are not metabolized and do not deteriorate, accumulating over the years. Recent research indicates that PFAS can cause liver damage and other serious health problems. Unfortunately, PFAS from playgrounds can get into the water supply. That is why numerous states and communities, as well as the federal government, are passing laws and regulations to protect our communities from PFAS exposure.

Federal agencies such as the EPA and the U.S. Consumer Product Safety Commission have been investigating the safety of artificial turf but have not conducted appropriate studies of playground surfaces.

Lead
As you probably know, lead can cause cognitive damage even at low levels. Some children are more vulnerable than others, and that can be difficult or even impossible to predict. Since lead has been found in recycled SBR rubber, it is not surprising that numerous playground surfaces made with either tire crumb or PIP have been found to contain lead. The lead doesn’t just stay on the surface. With wear, the materials turn to dust containing lead and other chemicals that are invisible to the eye and are inhaled by children when they play.

Why are chemicals that are banned from children’s toys allowed in artificial turf and rubber playground surfaces?
Synthetic rubber is made with different types of endocrine (hormone) disrupting  chemicals (also called EDCs). There is very good evidence regarding these chemicals in tire crumb, based on studies done at Yale and by the California Office of Environmental Health Hazard Assessment (OEHHA).1 However, rubber playground surfaces like EPDM contain many of the same dangerous chemicals as tire crumb, since they are very similar materials, all made from petroleum.

There are numerous studies indicating that these hormone-disrupting chemicals found in rubber (and plastic) cause serious health problems. Scientists at the National Institute of Environmental Health Sciences (which is part of NIH) have concluded that unlike most other chemicals, hormone-disrupting chemicals can be dangerous at very low levels, and the exposures can also be dangerous when they combine with other exposures in our environment.

That is why the U.S. Consumer Product Safety Commission has banned numerous hormone-disrupting chemicals from toys and products used by children. The products involved, such as pacifiers and teething toys, are banned even though they would result in very short-term exposures compared to playground surfaces.

A report warning about possible harm to people who are exposed to rubber and other hormone-disrupting chemicals at work explains that these chemicals “can mimic or block hormones and disrupt the body’s normal function, resulting in the potential for numerous health effects. Similar to hormones, endocrine-disrupting chemicals can function at very low doses in a tissue-specific manner and may exert non-traditional dose–response because of the complicated dynamics of hormone receptor occupancy and saturation.”

Studies are beginning to demonstrate the contribution of skin exposure to the development of respiratory sensitization and altered pulmonary function. Not only does skin exposure have the potential to contribute to total body burden of a chemical, but also the skin is a highly biologically active organ capable of chemical metabolism and the initiation of a cascade of immunological events, potentially leading to adverse outcomes in other organ systems.

Scientific Evidence of Cancer and Other Systemic Harm
It is essential to distinguish between evidence of harm and evidence of safety. Companies that sell and install PIP playground surfaces often claim there is “no evidence children are harmed” or “no evidence that it causes cancer.” This is often misunderstood as meaning the products are safe or are proven to not cause harm. Neither is true.

It is true that there is no clear evidence that a specific playground has caused specific children to develop cancer, asthma, or other serious diseases. However, the statement is misleading because it is virtually impossible to prove any chemical exposure causes one specific individual to develop a disease. As an epidemiologist, I can also tell you that for decades there was no publicly available evidence that cigarettes or Agent Orange caused cancer. It took many years to develop that evidence, and the same will be true for artificial turf and playground surfaces.

I have testified about the risks of these materials at the U.S. Consumer Product Safety Commission, the Centers for Disease Control and Prevention (CDC), the Environmental Protection Agency (EPA), as well as state agencies, state legislatures, and city councils. I am sorry to say that I have repeatedly seen and heard scientists and lobbyists paid by the PIP and rubber industries say things that are absolutely false. They claim that these products are proven safe (not true) and that federal agencies have stated there are no health risks (also not true). They also claim that the products do not contain PFAS or lead, but independent researchers find those claims are also false.

We know that the materials being used in rubber playground surfaces contain toxic chemicals, and when children are exposed to those chemicals day after day, week after week, and year after year, they increase the chances of our children developing serious diseases, either in the next few years or later as adults. That should be adequate reason not to install them in your community. That’s why I have spoken out about these risks in my community and on a national level. The question must be asked: if they had all the facts, would your community choose to spend millions of dollars on playgrounds that are less safe than those using engineered wood fiber, which is safely used in playgrounds across the country?

Dangerously Hot
Outdoor rubber surfaces become significantly hotter than ambient temperatures. Even when the temperature above the grass or engineered wood fiber is 80 degrees Fahrenheit, rubber playground surfaces can reach 150 degrees or higher. On a sunny 90-degree day, we’ve measured temperatures as high as 180 degrees Fahrenheit just above these surfaces. These temperatures can cause “heat poisoning” as well as burns.

Alternative Playground Surfaces
Engineered wood fiber products are a safe material for playground surfaces and are ADA compliant. If the surface gets uneven, it can easily be raked.  Sidewalks to the playground can also help make them even more easily accessible. Don’t be fooled by other wood products, such as BrockFILL, which has been scientifically tested and found to contain PFAS, the “forever chemicals” that I referred to earlier in this letter. In addition, the Brock shock pad also tested positive to PFAS.

Conclusions  
There have never been any safety tests required prior to sale that prove that PIP or recycled tire crumb playground surfaces are safe for children who play on them regularly. In many cases, some of the materials used are not publicly disclosed, making independent research difficult to conduct. None of these products are proven to be as safe as engineered wood fiber.

I have cited several relevant scientific articles on artificial turf in this letter, and there are numerous studies and growing evidence of the harm caused by these synthetic materials. I would be happy to provide additional information upon request (dz@center4research.org).

I am not paid to write this statement. I am one of the many parents and scientists who are very concerned about the impact of artificial fields on our children. Your decision about playground surfaces can save lives and improve the health of children in your community. You owe it to your community to make sure that you do all you can to protect your children from both the known risks and the suspected risks. Your decisions will be cited by other communities, making it even more important that your decision is based on scientific evidence, not on sales pitches by individuals with conflicts of interest.

Officials in communities all over the country have been misled, erroneously told that these products are safe. On the contrary, there is clear scientific evidence that these materials are harmful. The only question is how much exposure is likely to be harmful to which children? We should not be willing to take such a risk. Our children deserve better.

Sincerely,
Diana Zuckerman, Ph.D.
President
National Center for Health Research

References
[1] State of California-Office of Environmental Health Hazard Assessment (OEHHA), Contractor’s Report to the  Board. Evaluation of Health Effects of Recycled Waste Tires in Playground and Track Products. January 2007.  http://www.calrecycle.ca.gov/publications/Documents/Tires%5C62206013.pdf

[2] Anderson SE and Meade BJ. Potential Health Effects Associated with Dermal Exposure to Occupational  Chemicals. Environmental Health Insights. 2014; 8(Suppl 1):51– 62. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4270264/