April 10, 2024

Today I will talk about Chemicals and Heavy Metals in Artificial Turf, Playgrounds, and Neighborhood Lawns: Policies vs. Scientific  Evidence.

I’m Dr. Diana Zuckerman and I’m president of the National Center for Health Research. Our nonprofit research center and think tank is staffed by scientists, medical professionals, and public health experts. We conduct and explain research that can improve the health and safety of adults and children. We do not accept funding from companies whose products we evaluate, so we have no conflicts of interest.

Artificial turf and rubber tiles, mulch, and rubber playground surfaces contain lead, PFAS and other risky hormone-disrupting chemicals (EDCs) and heavy metals. Crumb rubber is used for turf infill and rubber mulch and tiles and contain lead and EDCs. When we look at the beautiful rubber playground surfaces, such as the one pictured here, they look very inviting. They feel spongy and that seems especially safe when small children fall. But what happens when children are exposed day after day, week after week, and year after year? This is especially true for playgrounds used daily by daycare centers and elementary schools.

Some playground surfaces are covered with recycled tire mulch or “virgin rubber.” contain lead? They vary in color. None are tested for metals or chemicals before they are sold.

Poured in Place (PIP) is a very popular type of surface for playgrounds, and consists of what looks like a solid rubber surface, but underneath the surface is recycled tire mulch. Sometimes the top surface may be virgin rubber, but sometimes it is also made of recycled tire mulch. Testing has shown chemicals and heavy metals, even in dust on the surface.

Rubber playground surfaces contain hormone-disrupting chemicals that can cause or exacerbate:

• Attention deficits
• Early puberty (and infertility in adults)
• Obesity
• Asthma and allergies
• And eventually cancer

Don’t be fooled by how they look when they are new

These photos show what happens to these very attractive rubber surfaces after a few years.  The rubber surfaces deteriorate, especially where children are most active. Some examples are at the foot of a slide, where children land when they go down the slide.  But the top layer also wears off in other areas where children play or when the top layer cracks due to the weather. The black you see is recycled tire mulch.  I’m not sure what the gray color on the ground is – probably the tire mulch washed away and left the hard surface underneath.

What’s below the rubber surface? Recycled tire mulch can be on the top layer of a playground surface or just below the top PIP (poured in place) solid layer.  You can see that in these close-up photos.  The surface on the left is made of pieces of rubber of different colors, whereas the top layer surface on the right looks orange from a distance but is actually from pieces of rubber that are yellow and red.  But look at what is under the surface.  The black is recycled rubber mulch. It looks a bit like licorice.  You can also see some color pieces of rubber that are mixed in with the black.  That looks like candy.  And small children like to play with it, and put it in their mouths.

From the ground into the air

When lead dust is found on the surface of playgrounds, officials often try to solve the problem by power washing the dust off the surface.  But where does the lead dust go when it is washed away?  The lead goes onto the dirt and sometimes into streams and ground water.  And of course, new lead dust will form on the surface after the previous dust is washed off.

In this photo you can see black specks which is tire crumb used as infill in an artificial turf field.  Did any of you watch the Superbowl this year?  That field used artificial turf, and although the plastic grass was nice and green, you could see black areas where the tire crumb infill was very visible.  And you could also see some of that infill flying around the feet of the players during the game.

Whether we’re talking about playgrounds or artificial turf fields, children and athletes breathe in the lead, chemicals, and particulate matter when they play. And small children eat pieces.

In a study of aerosolized particulate matter from artificial turf, a University of Georgia faculty member found particulate matter that contained arsenic, cadmium, chromium, and lead.1

Safety Tests

This photo of a new playground in Maryland shows the surface is made of recycled tire crumb that was dyed green.  Given the chances of tire pieces containing lead ending up in children’s clothes, on their hands, and in their mouths, this is probably the most unsafe playground possible.

No tests on human health were conducted prior to this product getting on the market.   Fortunately, several of us were invited by families in that community to speak at their town forum, and I’m glad to say that all these playground surfaces were replaced with a safe alternative called engineered wood fiber.   But meanwhile, we learned that there is a playground at NIH where very sick children play – kids that are so sick that they are undergoing treatment at NIH – that were also made with loose tire crumb similar to this.

U.S. government agencies restrict lead and some phthalates in numerous other children’s products. Agencies are starting to restrict PFAS. But these substances, VOCs, and other heavy metals are not restricted in artificial turf, rubber tiles, mulch, or playgrounds.

Here’s a sign that the D.C. government put up at artificial turf fields using recycled tire mulch as an infill.  It’s in English and Spanish.  If only toddlers could read!

The Consumer Product Safety Commission has warnings on their website that says:

• Avoid mouth contact with playground surfacing materials, including mouthing, chewing, or swallowing playground rubber. This may pose a choking hazard, regardless of chemical exposure
• Avoid eating food or drinking beverages while directly on playground surfaces, and wash hands before handling food.
• Limit the time at a playground on extremely hot days.
• Clean hands and other areas of exposed skin after visiting the playground, and consider changing clothes if evidence of tire materials (e.g., black marks or dust) is visible on fabrics.
• Clean any toys that were used on a playground after the visit.

These are very clear and important warnings, but how realistic are they.  Will busy parents and caregivers of young children really immediately wash children’s clothes and toys after going to a playground?

Another issue is how hot artificial turf and playgrounds covered with rubber can get. You can see from this photo that on a warm and sunny day in the Washington, DC area, when the air and grass were about 90 degrees, the artificial turf and playground were 180 degrees!  That is unusually hot, but I’ve frequently measured temperatures of 150 or 160 degrees when the air is less hot or the weather is less sunny, which is also dangerously hot.

Where does tire mulch infill go when it rains? Or when they can no longer be used?

In this photo, a heavy rain caused the recycled tire infill to wash off the artificial turf field onto other play areas nearby.  I’m glad to say that the father who took this photo got his kids off the tire crumb right after the photo was taken.  But this gives you an idea of how much tire mulch infill there is, and it has to go somewhere.  And it can’t be recycled, and in many cases it eventually gets into streams and ground water.  And by the way, when the infill washes off like this, the entire artificial turf field has to be replaced.  They can’t just replace the infill that has washed off.  Since these fields cost about $2 million dollars, this is a very expensive problem, because the fields don’t last 10 years as is often promised.

The companies claim that the old synthetic turf and tire crumb are recycled, but most of these materials can’t be recycled. As you can see, it often ends up in a dumpster, and from there to a landfill. They still contain lead and toxic chemicals.

Recycled Tire Crumb at Home

In this photo, you can see floor tiles made of recycled rubber, which are also widely available at Home Depot and other stores. They are proudly described as recycled rubber and therefore environmentally friendly, but if you want to find out that they are made of recycled tires you need to check the manufacturers’ websites to find that information. I don’t mean to pick on Home Depot – I mention it because these stores are in communities across the country. We are especially concerned about these tiles when used in daycare centers, playrooms, exercise rooms, or basements, because those rooms may have no windows or windows that are not usually opened.

Andrea Sun, MS, Cancer Prevention and Treatment Fund

Do you know how to pick out the right makeup or skincare products for yourself? Cosmetic products are used by everyone of all ages. They include shampoo, shaving products, and moisturizing creams, as well as make-up, nail polish, and anti-aging products. Promotional videos for cosmetic products are popular among influencers on social media platforms like YouTube and Instagram. Some studies show that the revenue in the U.S. Beauty & Personal Care market will exceed an astonishing $92 billion by the end of 2023.^[1]

U.S. consumers use an average of 6 to 12 cosmetic products daily, containing nearly 200 chemicals. With so many choices, and so many potentially risky chemicals, it’s essential to know what to look for when buying these products. Current regulations address some safety concerns for cosmetic products, but many gaps remain.

What are some of the regulations that protect us?

The U.S. has some regulations regarding the manufacturing and selling of cosmetics. Let’s look at what makes cosmetics different from drugs and what might be helpful information when you shop or read the label on a product.

The Federal Food, Drug & Cosmetic Act (FD&C Act) defines cosmetics as articles intended to make the human body more attractive. Lipsticks, nail polishes, perfumes, skin moisturizers, toothpaste, deodorants, and shampoos are especially popular cosmetics. However, there are some topical products that are sold without prescriptions in drug stores that are not considered cosmetics – they are considered drugs. Drugs are defined as products that can cure, mitigate, treat, or prevent diseases or affect the body’s function. For example, products such as hair loss treatment shampoo and acne medications are considered over-the-counter drugs instead of cosmetics. They are regulated by the FDA to make sure that they are safe and effective.

If a product makes you look better and treats your disease or improves your body’s function, it is both a cosmetic and a drug. One example is anti-dandruff shampoos, since they clean your hair and treat dandruff. Other products, such as deodorants containing antiperspirants, moisturizers, and makeup with sun-protection claims, are also drugs and cosmetics. These are also regulated by the FDA to determine if they are safe and effective.

The Modernization of Cosmetics Regulation Act of 2022 (MoCRA) requires manufacturers to list products’ ingredients and manufacturing information, report serious adverse events such as life-threatening reactions, and renew registered facility information at FDA. This law will go into effect on December 29, 2023. Another law, the Fair Packaging and Labeling Act (FPLA), works with MoCRA to ensure consumers receive accurate information. It requires clear labeling of essential information, such as the product’s name and manufacturer and sets standards for quantities and measurements to enable easy comparison across different products. The law also protects consumers from misleading information by prohibiting deceptive packaging or labeling and gives various government agencies the authority to enforce these rules.

The effect of cosmetics on environmental pollution is also limited through regulation. The Microbead-Free Waters Act of 2015 prohibits the manufacturing, packaging, and distributing of rinse-off cosmetics containing plastic microbeads. These tiny plastic particles usually appear in personal care products like facial scrubs, toothpaste, and body washes for their exfoliating properties. However, they pose significant environmental problems, since they could easily pass through water treatment facilities and end up in rivers and oceans. Marine animals could mistake them for food, which would endanger the food chain.

Cosmetic substances that cause health concerns

U.S. regulations require the disclosure of ingredients, but do not set limits on what chemicals can be included in these products. That means that ingredients known or suspected to cause cancer could be in cosmetics that are legally sold in the U.S. This includes chemicals like formaldehyde and formaldehyde-releasers, parabens, phthalates, fragrance, diethanolamine (DEA), and other heavy metals.

● Formaldehyde
Formaldehyde is added to many personal care products to prevent bacteria from growing. Customers sometimes find it in nail polish, shampoo, and body washes. Exposure to low levels can irritate people’s eyes, nose, and throat. However, hair stylists and manicurists who are regularly exposed are more likely to eventually develop nose and throat cancers. A 2019 study in Brazil looked at 23 beauty salons to understand the exposure of hairdressers to formaldehyde and its effects. The result shows that 17% of salons had exceeded the formaldehyde level that is considered safe. Over 65% of the hairdressers reported work-related health issues like eye irritation, skin problems, headaches, limb pain, and breathing difficulties. ^[8]

● Parabens
Parabens are preservatives commonly used in water-based products. Shampoos, conditioners, face washes, toothpaste, and other cosmetics contain low levels of parabens. Studies on animals indicate that parabens can imitate the actions of the hormone estrogen.^[3] that paraben exposure may increase the chances of developing breast cancer in women and disturbances in male reproductive systems. ^[2]

● Phthalates
Phthalates are chemicals that mimic hormones and are linked to birth defects in animals, especially in the male reproductive system, and are also considered a potential cause for early puberty in boys and girls. They also can increase obesity in children. Personal care product manufacturers started to phase out the direct use of phthalates in 2018 when the U.S. Consumer Product Safety Commission restricted six types of phthalates in children’s toys and child care products after learning about its risks in hormone function and fertility impairment. However, phthalates are still in many products, especially those that smell good.

● Fragrances
Fragrance ingredients are common in self-care products such as shower gels, shampoos, body lotions, and shaving creams. They sometimes are even in products labeled “unscented.” This is because manufacturers are not obligated to label the fragrance in the ingredient list if the amount added is just enough to cover the unpleasant smell of other ingredients versus giving the product a noticeable scent. In the U.S., manufacturers can list fragrance and flavor ingredients as “Fragrance” or “Flavor.” The fragrance is usually a company’s “trade secret,” so they do not need to disclose it. Diethyl phthalate, or DEP, is the phthalate commonly used in fragrance products and is not proven to harm people’s health.

● Diethanolamine
Diethanolamine, also called DEA, is an emulsifier in creamy or foamy products like shampoos and shaving creams. Its reaction with other preservatives in personal care products will form nitrosamines, a human carcinogen according to the International Agency for Research on Cancer and the U.S. National Toxicology Program. Europe and Canada prohibit DEA in cosmetics. Why doesn’t the U.S. FDA?

● Heavy metals
Personal care products such as lipstick, whitening toothpaste, eyeliner, and nail polish often contain heavy metals, including lead, arsenic, mercury, aluminum, zinc, chromium, and iron. Exposure to some of these metals can raise health concerns, particularly affecting the reproductive, immune, and nervous systems. Though “plant-source derived” might sound safe to many customers, several ingredients, such as cottonseed oils and rice derivatives, may contain heavy metals such as lead and mercury, which can harm fertility, cause brain damage, and harm breathing. Sometimes metals are deliberately added to cosmetics; for example chromium is commonly found in eye shadows, blushes, and concealers.

Cosmetics and the Environment

Ingredients from cosmetics can harm our environment. Products such as makeup remover wipes, exfoliating scrubs with microbeads, face sheet masks, skin-whitening creams, and sprays and mists contain non-biodegradable ingredients and chemicals that can harm the environment, waterways, marine life, and even the ozone layer. A 2023 study suggested that microplastics, tiny plastic particles between 100 nm and 5 mm, can move up the food chain from small sea creatures to larger ones, carrying harmful pollutants that could end up in humans.^[4]

Additionally, triclosan (TCS), an antimicrobial substance that is often in shampoos, detergents, hand soaps, toothpaste, sunscreen, and deodorants, can also damage the environment. A 2020 study shows that people are more likely to have TCS in their blood, urine, and breast milk if they apply personal care products containing TCS.^[5] This can harm human health and our environment, causing an itchy rash, decreased sperm production, and tumors. If TCS is in the environment, it becomes highly poisonous during wastewater treatment, accumulating in animals, plants, and algae, disrupting the ecosystem.

Does consistent exposure to cosmetics harm beauticians’ health?

Hair stylists, manicurists, aestheticians, and other beauticians are constantly exposed to chemicals and heat in their working environments. Do they have a higher risk of some diseases due to these exposures? What can they do to protect themselves from these exposures during work?

A 2021 study examined the chemical and physical conditions in hair salons and assessed the health risks of volatile organic compounds (VOCs) for hairdressers.^[6] VOCs are organic chemical components in hair spray that carry substances that can cause heart disease, irritation, insomnia, and nerve damage. This exposure also increases the chances of developing cancer. Installing exhaust ventilation is one of the most effective methods to lower the VOC concentration in the salon. Nail professionals in U.S. salons are also frequently exposed to dangerous chemicals in adhesives, lacquers, removers, moisturizers, and other salon items that can cause breathing problems, rashes, liver complications, reproductive issues, and even cancer. Chemicals found in nail products, such as acetone in nail polish remover, formaldehyde in nail polish and nail hardener, and toluene fingernail glue, can cause headaches, dizziness, allergic reactions, and harm the fetus during pregnancy. For that reason, nail salons should be required to make sure products are 3-free (free from toluene, formaldehyde, and dibutyl phthalate) and free from acid. Nail professionals should always review product labels and instructions when using nail products. ^[7]

So, what can you do to protect yourself while enjoying personal care products?

1. Read ingredient labels and remember that Ingredients appear in order from highest to lowest concentration. Pay attention to ingredients with higher concentration and avoid those you are allergic to or that can cause environmental problems. See ingredients you want to avoid in cosmetics.
2. When it comes to self-care routine, more is not necessarily better. Skin irritation can occur when layering products. Applying daily makeup without adequately removing it might also disrupt the skin’s protective barrier and cause eye infections and premature aging. Therefore, it is important to build a simple yet effective routine that works well for you and stick with it. Read here for more skin care tips.
3. Choose traditional nail polish over gel polish. Acetone is used to remove gel polish. Traditional nail polish is strong and doesn’t require remover made with acetone. If you use a remover made with acetone, soak a cotton ball in it to remove the polish. Read more here.
4. Cosmetic products that are less dangerous are usually better for the environment as well. Products with sustainable packaging such as refillable and reusable cosmetics can reduce plastic pollution.

All articles are reviewed and approved by Dr. Diana Zuckerman and other senior staff.

1. Beauty & Personal Care – United States. Statista. https://www.statista.com/outlook/cmo/beauty-personal-care/united-states
2. Sheikh, Knvul. Many Personal Care Products Contain Harmful Chemicals. Here’s What to Do About It. New York Times. 2023.
3. Hager, E., Chen, J., & Zhao, L. Minireview: Parabens Exposure and Breast Cancer. International journal of environmental research and public health, 19(3), 1873. https://doi.org/10.3390/ijerph19031873
4. Zhou, Yuwen., Ashokkumar, Veeramuthu., & Amobonye, Ayodeji. Current Research Trends on Cosmetic Microplastic Pollution and Its Impacts on the Ecosystem: A Review. Environmental Pollution. Vol. 320. 2023. https://doi.org/10.1016/j.envpol.2023.121106
5. Bilal, Muhammad., Mehmood, Shahid., & Lqbal, Hafiz. The Beast of Beauty: Environmental and Health Concerns of Toxic Components in Cosmetics. Cosmetics. 2020, 7(1), 13. https://doi.org/10.3390/cosmetics7010013
6. Senthong, P., & Wittayasilp, S. Working Conditions and Health Risk Assessment in Hair Salons. Environmental health insights, 15, 11786302211026772. 2021. https://doi.org/10.1177/11786302211026772
7. Health Hazards in Nail Salons. Occupational Safety and Health Administration. n.d. https://www.osha.gov/nail-salons/chemical-hazards
8. Pexe, M. E., Marcante, A., Luz, M. S., Fernandes, P. H. M., Neto, F. C., Sato, A. P. S., & Olympio, K. P. K. Hairdressers are exposed to high concentrations of formaldehyde during the hair straightening procedure. Environmental science and pollution research international, 2019; 26(26), 27319–27329. https://doi.org/10.1007/s11356-019-05402-9

May 4, 2023

I’m Dr. Diana Zuckerman, president of the National Center for Health Research. Our nonprofit think tank focuses on the safety of medical and consumer products.  We provide research-based information to Congress, federal agencies, and the public and we do not accept funding from companies that make the products we evaluate.

My comment today relies on my research experience at Yale and Harvard and in my current position, as well as my policy expertise from working in the House, Senate, federal agencies, and the White House.

We agree that this proposed rule will improve public health, reducing cancer, heart disease, stroke, low birth weight, and other harms to adults and children.  It will save lives. But we have recommendations to improve it.

1. We disagree that 4 ppt is the lowest level that can be reliably tested and removed. Eurofins routinely and reliably measures 2 ppt in water. And it is likely that 2 ppt will be widely usable to measure and remove PFOA and PFOS well before this rule is finalized.  Since EPA acknowledges that no level of PFOA and PFOS is safe, the limit should be 2 ppt.
2. We understand the agency’s desire to be flexible, but flexibility to satisfy monitoring requirements will likely generate a huge loophole.  EPA needs more explicit limits to prevent a weakening of these regulations
3. This proposed rule is an important first step, but it is long past time for the EPA to define PFAS broadly, regulate them as a class, and ban all non-essential uses.
4. Lastly, we appreciate the law that provides funding for these efforts, but it’s time to start shifting the costs to the companies that have made these chemicals. When  companies are held financially responsible, they will be less likely to inundate us with PFAS in products. Taxpayers are already stuck with the health risks. It is not fair for municipalities and taxpayers to get stuck with the work and the cost.

Diana Zuckerman, PhD, National Center for Health Research

Is your child playing on rubber and plastic instead of grass?  Grass has been replaced with artificial materials at schools and parks all over the country and especially in Washington D.C., Maryland, and Virginia. but there is growing evidence they can be harmful to children and adults.

Regardless of what they look like, all artificial fields and playgrounds are made with materials that can be dangerous to people of all ages.

Many athletes don’t like artificial turf, and only 2 professional ballparks now use it.  In addition to plastic “grass,” rubber, silica, and other materials are used to keep the “grass” in place and provide more cushioning.  Unfortunately, artificial turf increases “turf burn” abrasions from sliding, puts additional stress on joints, and can become dangerously hot in the sun.  It may also cause cancer and other serious long-term health problems.

 Recycling Tires from Playgrounds

More than 20 million recycled rubber tires are processed every year for playground surface cover and sports surfaces. Using tire scraps seemed like a great idea at first – keeping them out of landfills and providing a potentially softer landing on the playground. It was known that burning old tires released harmful, smelly chemicals into the air and ground water, but parents didn’t realize that recycled tires and new rubber used on fields and playgrounds (such as pictured below) can also be dangerous. You may think of rubber as a natural product from rubber trees – but rubber is a mix of latex from rubber trees mixed with petroleum products.  That means it can include lead, phthalates, polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), and other chemicals known or suspected to harm human health. For example, phthalates are chemicals that affect hormones and many have been banned from children’s toys because they can increase the risks of obesity, early puberty, attention problems, and cancer. The EPA warns that breathing air contaminated with PAHs may increase the chance of developing cancer, and the U.S. Agency for Toxic Substances and Disease Registry warns that PAHs may increase the risk of cancer and birth defects.

 Why Aren’t They Proven Safe?

There is no government agency that requires synthetic playground surfaces to be tested before they can be sold. In fact, the materials used are often not made public — justified as “trade secrets.”  However, some researchers independently have examined the safety of these playground surfaces, resulting in signs like the local one below.

It would not be ethical to conduct a study exposing children to tire shreds, knowing they could be unsafe, so the California Office of Environmental Health Hazard Assessment conducted three studies that mimicked children’s exposures instead.  Results showed that a single incident of eating or touching tire shreds would probably not harm a child’s health, but repeated or long-term exposure might. Five chemicals, including four PAHs, would get on children’s skin if they played on these surfaces. One of the PAHs, “chrysene,” was higher than the level considered safe, and could increase the chances of a child developing cancer.

In addition, only 10 of the 32 playgrounds studied met California’s safety standard for falls, which meant that falling on these hard surfaces could cause a brain injury of other serious harm. In contrast, all five surfaces made of wood chips met the safety standard.

In Washington, D.C., 37 of their 51 artificial turf fields failed 2017 safety tests, due to hardness scores above 165 (see the sign above). In 2019, Washington, D.C. admitted that 17 of their playgrounds have dangerously high levels of lead.  Also in 2019, the nonprofit Ecology Center tested the crumb rubber that was found on the broken rubber surfaces of several playgrounds in Washington, D.C.  They found that some of the pieces had dangerously high levels of lead.

A 2015 report by Yale scientists analyzed 14 different samples used for school athletic fields and playgrounds.  They detected 96 chemicals, most of which have never been carefully studied, so their health risks are unknown.  However, 20% of the chemicals that had been tested are considered to probably cause cancer.  In addition, 40% are irritants that can cause breathing problems such as asthma, and can irritate skin or eyes.

What About your Schools or Parks?

These are a few of the many materials to be concerned about:

• Loose tire shred (rubber mulch) or “crumb” on a surface that can be raked, including artificial “grass” fields.
• Tire shreds that are combined with a binder and then poured onto a permanent surface.
• Tiles made from tire shreds and binder that have been factory-molded, then glued to a playground surface.
• Colorful rubber that is “poured in place” (PIP), which is not necessarily made from tires but can contain many of the same dangerous materials.

How to Protect your Children

Children are much more likely to be harmed by exposure to chemicals in their environment than adults because they are smaller (so the exposure is greater) and because their bodies are still developing. Pregnant women should be even more careful to avoid these exposures.

Parents in many communities are persuading local officials to conduct safety tests on artificial turf fields every year, and to  install grass or wood chips because they are safer in terms of chemical exposure, heat, and if their children fall.

Meanwhile, here are some tips for parents from the Consumer Product Safety Commission: 

1. Children should avoid mouth contact with playground surfacing materials. Some of these materials are small and look like seeds, mulch, or small candies. They may pose a choking hazard as well as a dangerous chemical exposure.
2. Avoid eating food or drinking beverages while directly on playground surfaces, and wash hands before handling food.
3. Limit the time at a playground on hot days. Children tell us they can often see the heat waves rising off the fields on warm, sunny days.
4. Clean hands and other exposed skin after visiting the playground, and consider changing clothes if marks or dust from the rubber is visible on fabrics.
5. Clean any toys that were used on a playground after the visit.

These safeguards will help reduce your child’s exposure, but if they are playing on one of these fields or playgrounds for hours every week, there is still reason for concern.

That’s why our Center has testified before the Washington, D.C. City Council and the Maryland Senate and House of Delegates and why we are working with parents across the country who seek our help in convincing their communities to choose grass and avoid artificial turf.

If you would like to download and print a PDF version, click here.

References:

1. Llompart M, Sanchez-Prado L, Lamas JP, Garcia-Jares C, et al. Hazardous organic chemicals in rubber recycled tire playgrounds and pavers. Chemosphere. 2013;90(2):423-431. http://www.sciencedirect.com/science/article/pii/S0045653512009848
2. US Environmental Protection Agency (EPA). Polycyclic Aromatic Hydrocarbons (PAHs)-Fact Sheet. November 2009. https://www.epa.gov/north-birmingham-project/polycyclic-aromatic-hydrocarbons-pahs-fact-sheet Accessed May 2016.
3. Agency for Toxic Substances and Disease Registry (ATSDR). Polycyclic Aromatic Hydrocarbons. September 1996. http://www.atsdr.cdc.gov/toxfaqs/tfacts69.pdf Accessed May 2016.
4. 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 Accessed May 2016.
5. Yale Study Reveals Carcinogens and Skin Irritants in Synthetic Turf. http://wtnh.com/2015/09/03/new-yale-study-reveals-carcinogens-and-skin-irritants-in-synthetic-turf/

Nyedra W. Booker PharmD MPH and Stephanie Fox-Rawlings PhD, National Center for Health Research.

Is your child playing on rubber instead of grass at the playground? The use of human-made surfaces on playgrounds has increased dramatically over the years. First developed in 1964, the first artificial turf was marketed as “Chemgrass” by Monsanto, and renamed Astroturf more than 2 years later when it was installed at the Houston Astro’s Astrodome football field.¹ 

In recent years, the use of artificial grass has become common, and playgrounds for young children are also made of artificial surfaces that look and feel like colorful rubber. When artificial turf was introduced in the 1960’s and rubber playground surfaces were introduced years later, nobody was concerned about microplastics in our bodies, PFAS forever chemicals, or lead in rubber mulch made from recycled tires.  But, research tells us that regardless of what they look like, artificial turf and rubber playground surfaces are all made with materials that can be dangerous for children and adults, and for our environment.

As the use of artificial turf for various sports activities increased significantly over the years, so did the concerns. Athletes began to complain that the surface was much harder than natural grass, and some studies began to show that the use of artificial turf could increase the risk of sports-related injuries. This prompted a ban on the use of artificial turf by the English Football Association in 1988, and many ballparks and professional sports stadiums in the United States began converting back to using natural grass during the 1990s. Over time,“infill” material such as recycled tire rubber was added to keep the blades of “grass” in place and provide more cushioning.¹ Artificial turf containing rubber and other cushioning materials was also assumed to reduce sports-related injuries, but study results have not supported that assumption.² Many professional athletes dislike playing on artificial turf. It increases the severity of abrasions due to sliding, puts additional stress on joints, and heats up much more than grass does in the sun – and can become dangerously hot.^3,4 Following their failure to force soccer’s international governing body (FIFA) to use sod instead of artificial turf for the 2015 Women’s World Cup, an international group of women players sued FIFA, although they ultimately dropped the law suit when FIFA refused to budge.⁵

Unwanted used tires used to be burned, but doing so released many different harmful chemicals into the air and ground water. We now know that tire rubber doesn’t need to be on fire to release chemicals into the air we breathe.⁶ Those chemicals can also get on our skin and clothes and even be inhaled into our lungs. 

Recycled tire crumb is often still used as an infill for artificial turf, although it is much more controversial than it used to be. Recycled tire material and other rubber is also used on playground surfaces for young children.

Recycling tires for use in artificial turf and playground surfaces seemed like a good idea, because it is a relatively soft surface that seems safer than dirt or grass. And recycling keeps old tires out of landfills where they take up space, harbor rodents and other animals, and trap standing water that serve as breeding grounds for mosquitoes and other disease-bearing insects.

Are Playground Surfaces Made With Rubber or Tire Crumb Safe?

Do you remember when children used to play on tire swings in the backyard or at the park? Those same tires are now being put to use in playgrounds for young children across the country. Recycled rubber tires have become one of the top choice materials for surfacing children’s playgrounds.⁸ Approximately 290 million tires are discarded in the U.S. annually,⁶ of which approximately 12% were processed for sports fields and playground surfaces.⁹

Did you think that rubber comes from a rubber plant and is therefore a safe and natural product? While rubber sold in the U.S. includes some natural rubber (called latex) from rubber trees, it also contains phthalates (chemicals that affect hormones), polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs) and other chemicals known or suspected to cause adverse health effects.¹⁰ PAHs, for example, are natural or human-made chemicals that are made when oil, gas, coal or garbage is burned.¹¹ According to the EPA, breathing air contaminated with PAHs may increase a person’s chance of developing cancer, and the Agency for Toxic Substances and Disease Registry (ATSDR) states that PAHs may increase the risk for cancer and also increase the chances of birth defects.^11,12

There are several different ways that recycled tire mulch and new rubber is
used on children’s playgrounds:

• Loose tire shred (rubber mulch) or “crumb” on a surface 
•  Tire shreds that are combined with a binder and then poured onto a surface that looks like solid rubber (called “Pour in Place”, or PIP)
•  Tiles made from tire shreds and binder that have been factory-molded, then glued to a playground surface.⁸
• Colorful rubber that is “poured in place” (PIP) that is not necessarily made from tires but contains many of the same dangerous materials.

Engineered Wood Fiber is a natural alternative to rubber surfaces for playgrounds and feels surprisingly soft and spongy. It looks like wood mulch but is made in a way that does not cause splinters, and they are not made with dangerous chemicals. Researchers at Harvard School of Public Health examined levels of lead in poured-in-place rubber playground surfaces and compared them to levels in soil, sand, and wood mulch materials from 28 randomly selected playgrounds in Boston.¹³ They found that average lead levels were more than twice as high for rubber as for sand or wood mulch. They concluded that the lower concentrations of lead in sand and wood mulch “should be used to inform playground design to optimize children’s health.”

What the Scientific Studies Say About Tire Waste

The California Office of Environmental Health Hazard Assessment (OEHHA) conducted three laboratory studies in 2007 to investigate the potential health risks to children from playground surfaces made from tire waste. One study evaluated the level of chemicals released that could cause harm to children after they have had contact with loose tire shreds, either by eating them or by touching them and then touching their mouth. The other two studies looked at the risk of injury from falls on playground surfaces made from tire waste compared to wood chips, and whether tire shreds could contaminate air or water.¹⁴

It would not be ethical to ask children to eat tire shreds, so the researchers created a chemical solution that mimicked the conditions of a child’s stomach and placed 10 grams of tire shreds in it for 21 hours at a temperature of 37°C. Researchers then measured the level of released chemicals in the solution and compared them to levels EPA considered risky.¹⁴ The study also mimicked a child touching the tire shreds and then touching her mouth by wiping recycled tire playground surfaces and measuring chemical levels on the wipes. To evaluate skin contact alone, the researchers tested guinea pigs to see if rubber tire playground samples caused any health problems. This study assumed that children would be using the playground from the ages of 1 through 12. Results of the OEHHA studies showed that a single incident of eating or touching tire shreds would probably not harm a child’s health, but repeated or long-term exposure might. Five chemicals, including four PAHs, were found on wipe samples. One of the PAHs, “chrysene,” was higher than the risk level established by the OEHHA, and therefore, could possibly increase the chances of a child developing cancer.

It is difficult to determine the level of exposure that can cause cancer. Just think of how many decades it took to prove that smoking causes lung cancer, and how many years after that before research showed that smoking causes breast cancer and other cancers as well. But in 2022, a study published in the Journal of the National Cancer Institute found that greater exposure to phthalates while in utero through age 19 years increased the chances of developing childhood cancer.¹⁵ Although the study is specifically about the phthalates used in medical products, the exposure is clearly relevant to other types of phthalate exposure, including phthalates in artificial turf.

A study for the New Jersey Department of Environmental Protection analyzed lead and other metals in particulate matter (dust) that is kicked up into the air by activity on the field, and thus, able to be inhaled, on 5 artificial turf fields.¹⁶ The study found that there was more particulate matter that could be inhaled in the air around a moving object (such as a child soccer player) than a stationary collection system on the side of the field. This suggests that studies using stationary collection systems underestimate exposures. It also suggests that even low levels of activity on the field can cause particulate matter to get into the air where it can be inhaled and thus be harmful. The oldest field studied (8 years old) had more inhalable particulate matter than the younger fields (1-3 years old) in this study. The authors concluded that, “the results suggest that there is a potential for inhalable lead to be present on turf fields that have significant amounts of lead present as detectable by surface wipes. Since no level of lead exposure is considered safe for children, “only a comprehensive mandated testing of fields can provide assurance that no health hazard on these fields exists from lead or other metals used in their construction and maintenance.”

A 2013 study analyzing rubber mulch taken from children’s playgrounds in Spain found harmful chemicals in all, often at high levels.¹⁰ Twenty-one samples were collected from 9 playgrounds in urban locations. The results showed that all samples contained at least one hazardous chemical, most contained high concentrations of several PAHs, and all released hazardous chemicals into the air, where they can be inhaled. Several of the identified PAHs can be released into the air by heat, and when that happens children are likely to inhale them. While the heat needed to do this was very high in some cases (140ºF/ 60ºC), many of the chemicals also became airborne at a much lower temperature of 77ºF (25ºC). The authors concluded, “The present study highlights the presence of a high number of harmful compounds, frequently at high or extremely high levels, in these recycled rubber materials. Therefore, they should be carefully controlled, and their final use should be restricted or even prohibited in some cases.” ¹⁰

A 2014 study evaluated recycled rubber infill that was either already installed or was yet to be installed, as well as one new sample from new “virgin” rubber.¹⁷ It found that levels of cadmium and zinc exceeded regulatory requirements for some or all samples, respectively. It also found very high levels of PAHs released into the air from some samples. After calculating a risk assessment for PAH inhalation from synthetic fields, the authors stated that “the quantity of toxic substances it releases when heated does not make it safe for public health.”

A 2018 study examined particulate matter and chemicals from 1 sample of recycled tire rubber, 2 new tire rubber, a single 7-year-old sample of natural rubber, and 1 sample of last-generation thermoplastic elastomer crumb (TPE).¹⁸ The recycled tire rubber had a greater concentration of toxic elements, such as heavy metals. TPE released the lowest amount of elements with high concentrations of only magnesium and calcium. Natural rubber was more sensitive to aging and more easily broke down into small pieces that could be inhaled. The authors concluded, “The use of natural rubber and of not-recycled thermoplastic materials, which are progressively replacing recycled tire scraps as synthetic turf fillers, does not seem to be adequately safe for human health, particularly when considering that children are the most exposed bracket of population. Exposure risks arising from the use of these materials deserve to be further deepened.”

A 2018 study in Spain evaluated the amount of chemicals released into the air from samples of recycled tire rubber infill from 15 soccer fields.¹⁹ They found high levels of PAHs, including the highly toxic B[a]P. The levels of PAHs exceeded REACH Regulations for consumer products. The study also found heavy metals such as cadmium, chromium and lead, as well as phthalates, adipates, vulcanizing agents and antioxidants that could leach into runoff. They concluded that “The environmental and health risks derived from the use of these surfaces have to be considered and some regulations should be adopted.

A 2018 report by Yale University scientists analyzed the chemicals found in 6 samples of tire crumbs from different companies that install school athletic fields, and 9 different samples taken from 9 different unopened bags of rubber mulch intended for household use.²⁰  The researchers detected 92 chemicals in the samples. A little under a half have never been studied for their health effects, so their risks are unknown, and the other chemicals have been tested for health effects, but those tests were not thorough. Based on the studies that were done, 20% of the chemicals that had been tested are considered to probably can cause cancer, and 40% are irritants that can cause breathing problems such as asthma, and/or can irritate skin or eyes. They concluded that “ people routinely ingest, inhale, handle, and have abrasions which contact ground tire material. That being so, it is prudent to assume that any chemicals in the tires or released by them can be transferred to exposed individuals. This study shows that a large number of compounds, many of them carcinogenic or irritants, are released from shredded recycled tires through several potential routes. Caution would argue against use of these materials where human exposure is likely, and this is especially true for playgrounds and athletic playing fields where young people may be affected.”

A 2019 Yale study based on previously published research, identified 306 chemicals found in crumb rubber.²¹ Fifty-two of these chemicals were classified as carcinogens by the U.S. EPA and/or the European ECHA. Then the researchers used the known characteristics of each chemical, such as the structure, to predict whether or not it was likely to be a carcinogen. Using this process, 197 were predicted to be carcinogens. They concluded, “Our study highlights a vacuum in our knowledge about the carcinogenic properties of many chemicals in crumb rubber infill.” “The crumb rubber infill of artificial turf fields contains or emits chemicals that can affect human physiology.”

In the last few years, scientists have learned more about lead and PFAS in artificial turf, as well as the risks of some of the newer infill materials that are available to replace tire crumb. Tire crumb has well-known risks, as noted in the studies above, containing “hormone-disrupting chemicals” also known as “endocrine-disrupting chemicals.” By affecting the hormones that children need for healthy development, these chemicals have the potential to increase obesity; contribute to early puberty; cause attention problems such as ADHD; exacerbate asthma; and eventually cause cancer. 

The use of silica sand and other infill materials also has substantial risks.  For example, it is well known that tiny, often microscopic particles known as “particulate matter” can cause lung problems and eventually cause lung cancer.  For that reason, silica sand and zeolite used as infill are of great concern. Envirofill is a brand of infill that used to advertise its product as made of polymer coated “silica sand” but now that the American Lung Association and other experts explain that inhaling silica can cause lung damage and even lung cancer, the company now refers to their product as containing “sand” instead of “silica sand.” The manufacturers and vendors of these products claim that the silica stays inside a plastic coating. However, sunlight and the grinding force from playing on the field breaks down the plastic coating. For that reason, the Envirofill product warranty used to specify that only 70% of the silica will remain encapsulated, which would imply that the other 30% can be very harmful as children are exposed to it in the air as particulate matter that can harm the lungs. The currently worded warranty states that the warranty lasts 16 years but does not specify the percentage of pieces of infill where the sand remains intact inside the plastic coating.

PFAS chemicals 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. Although manufacturers often claim that their products do not contain PFAS, that is based on very limited testing. There are thousands of PFAS chemicals, and some worrisome PFAS chemicals have been found by independent researchers studying artificial turf, including but not limited to BrockFILL artificial turf.  Please note that while the manufacturer claims that BrockFILL “meets the requirements of the FIFA quality programme for synthetic turf systems as well as those of World Rugby” those requirements do NOT evaluate long-term safety for either children or adults. Unfortunately, there are zero testing criteria for artificial turf materials’ long-term safety, making such claims misleading as well as meaningless.

In addition to the infill, the plastic grass itself exposes children and adults to dangerous levels of PFAS, microplastics, and other toxic chemicals as well.

Injuries

Out of the 32 playgrounds surfaced in recycled tires that researchers in California looked at, only 10 met that state’s 2007 standard for “head impact safety” to reduce brain injury and other serious harm in children who fall while playing.¹⁴ In contrast, all five surfaces made of wood chips met the safety standard.

Artificial turf fields get hard over time which is why they need to be watered regularly to comply with the warranty. Turf companies recommend annual tests at 10 locations on each turf field, using something called a Gmax score. A Gmax score over 200 is considered extremely dangerous, and it is considered by industry to pose a death risk. However, the synthetic turf industry and American Society for Testing and Materials (ASTM), suggest scores should be even lower — below 165 to ensure safety comparable to a grass field. When concerned parents and public health advocates convinced Washington, D.C. government officials to test the hardness of artificial turf fields at schools, more than 20% of the 52 fields tested failed, even though the city used less stringent standards for failing than the turf industry recommends.²²

The hardness of natural grass fields is substantially influenced by rain and other weather; if the field gets hard, rain or watering will make it safe again. In contrast, once an artificial turf field has a Gmax score above 165, it needs to be replaced because while the scores can vary somewhat due to weather, the scores will inevitably get higher because the turf will get harder. 

It is well known that artificial turf fields and rubber surface playgrounds are much hotter than the air or grass on summer days. Our own research found that on warm or sunny days, the heat of the air just above artificial turf and rubber playground surfaces can be 50-60 degrees hotter than the temperature of the air or of natural grass. So, for example on a 90 degree day, the grass is also approximately 90 degrees, but artificial turf and rubber playgrounds often exceed 150 degrees Fahrenheit. That can cause “heat poisoning” as well as burns.

Lead

The American Academy of Pediatrics states that no level of lead exposure should be considered safe for children, because lead can cause cognitive damage even at low levels.²³ Some children are more vulnerable than others, and that can be difficult or even impossible to predict. The Centers for Disease Control and Prevention (CDC) warns that the “plastic grass” made with nylon or some other materials also contains lead.²⁴ Whether from infill, plastic grass, or rubber playground surfaces (including PIP, which is made with tire crumb on the top layer or underneath the top “poured in place” layer), the lead doesn’t just stay on the surface. With wear, the materials used in rubber playground surfaces turn to dust containing lead and other chemicals that is invisible to the eye and is inhaled by children when they play. In addition, PIP surfaces wear out and crack, and the tire crumb are then on the surface where small children like to play with it and put it in their mouths.

Why are chemicals that are banned from children’s toys allowed in artificial turf and rubber playground surfaces?

As noted earlier in this article, numerous studies indicate that the hormone-disrupting chemicals found in rubber and plastic cause serious health problems. That is why the Consumer Product Safety Commission has banned several endocrine-disrupting chemicals from toys and products used by young children. The products involved, such as pacifiers and teething toys, are banned even though they would result in very short-term exposures compared to artificial turf or playground surfaces.

Scientific Evidence of Cancer and Other Serious Harm

It is essential to distinguish between evidence of harm and evidence of safety. Companies that sell and install artificial turf often claim there is “no evidence children are harmed” or “no evidence that the fields cause 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 conclusive evidence that a specific artificial turf field has caused specific children to develop cancer. However, the statement is misleading because it is virtually impossible to prove any chemical exposure causes one specific individual to develop cancer. For example, for decades there was no evidence that smoking or Agent Orange caused cancer. It took many years to develop that evidence, and the same will be true for artificial turf.  We know that the materials being used in artificial turf and rubber playground surfaces contain carcinogens, and when children are exposed to those carcinogens day after day, week after week, and year after year, they increase the chances of our children developing cancer, either in the next few years or later as adults.

We are sorry to say that when NCHR experts have testified at public meetings, we have seen and heard scientists paid by the artificial turf industry 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).

What the U.S. Government Says

Federal agencies such as the EPA and the U.S. Consumer Product Safety Commission have been investigating the safety of these products. Despite claims to the contrary, no federal agencies have concluded that artificial turf is safe. For example, the 2024 EPA report that the artificial turf industry claims as proof that artificial turf is safe was not a “risk assessment” evaluating the impact of artificial turf fields on children. If focused only on tire crumb, not on PFAS, microplastics, or other exposures typical of artificial turf fields whether or not they have tire crumb infill.  Unfortunately, the EPA report was focused on issues that were selected many years ago, and not on the exposures or the health issues and environmental issues of greatest concern today.

The EPA created a working group that collected and analyzed data from playgrounds and artificial turf fields that used tire material. Samples were collected at six turf fields and two playgrounds in four study sites (Maryland, North Carolina, Georgia and Ohio). In a report released in 2009, the agency concluded that the level of chemicals monitored in the study and detected in the samples were “below levels of concern.” However, the study did not measure the concentration of organic chemicals that are known to vaporize during summer heat (called SVOCs). SVOCs include PAH. And, the EPA concluded that while there were currently no human studies available to determine the effects of PAHs at various levels, based on laboratory findings, “breathing PAHs and skin contact seem to be associated with cancer in humans.” ¹¹

What is the Impact on Our Environment?

Although this article focuses on the impact of artificial turf on health, it is worth noting that artificial turf also has a negative impact on the environment. Artificial turf fields are made of polyethylene and sometimes nylon so they produce greenhouse gasses.²⁵ The “outgassing” from the plastic is higher during the day but continues at lower levels at night. Because the artificial turf fields have millions of fragments, they have a very high surface area that produces much more greenhouse gas than a flat carpet would.

Approximately three tons of infill materials migrate off each synthetic turf field into the surrounding environment each year. About 2-5 metric tons of infill must be replaced every year for each field, meaning that tons of the infill have migrated off the field into grass, water, and our homes.²⁶ The fields also continuously shed microplastics as the plastic blades break down.^{27, 28} These materials may contain additives such as PAHs, flame retardants, and UV inhibitors, which can be toxic to marine and aquatic life. Microplastics are known to migrate into the oceans, the food chain, and drinking water, and they can absorb and concentrate other toxins from the environment.^{29, 30, 31}Tire crumb from artificial turf washes away into nearby grass and waterways, and when the fields are replaced after approximately 8 years, the plastic and the rubber end up in landfills. Despite claims to the contrary, most artificial turf is not recycled because most of the components cannot be recycled.⁷ 

Synthetic surfaces also create heat islands.^{32, 33} In contrast, organically managed natural grass saves energy by dissipating heat, cooling the air, and reducing energy to cool nearby buildings. Natural grass and soil protect groundwater quality; biodegrade polluting chemicals and bacteria; reduce surface water runoff; abate noise; and reduce glare.³⁴

How to Protect your Children

So how can you protect your child at the playground? Remember that children are much more likely to be harmed by exposure to chemicals in their environment than adults because they are smaller (so the exposure is greater) and because their bodies are still developing. This is why it’s important to significantly reduce (or try to eliminate) any contact your child may have with substances that are known or suspected to be harmful. If you have more than one playground in your area, choose the one that doesn’t have a recycled rubber play surface or other types of rubber or synthetic surface.

Parents can actively persuade local officials that playgrounds should use wood chips rather than rubber or other substances that are less safe when children fall, and more dangerous in terms of chemicals that they breathe or get on their hands.

The CDC, Consumer Product Safety Commission (CPSC) and EPA all recommend that you teach your child the importance of frequent hand washing, especially after playing outside and before eating.²⁰ The President’s Cancer Panel advised to “minimize children’s exposure to toxics” and “both mothers and fathers should avoid exposure to endocrine-disrupting chemicals and known or suspected carcinogens prior to a child’s conception and throughout pregnancy and early life, when risk of damage is greatest.” ³⁵

The Consumer Product Safety Commission recommends the following precautions:

1. Avoid mouth contact with playground surfacing materials, including mouthing, chewing, or swallowing playground rubber. This may pose a choking hazard, regardless of chemical exposure.
2. Avoid eating food or drinking beverages while directly on playground surfaces, and wash hands before handling food.
3. Limit the time at a playground on extremely hot days.
4. Clean hands and other areas of exposed skin after visiting the playground, and consider changing clothes if evidence of tire materials (e.g., black marks or dust) is visible on fabrics.
5. Clean any toys that were used on a playground after the visit.³⁶

To learn more about artificial turf and concerns about cancer risks for kids and young adults, watch this ESPN news video here.

Conclusions

There have never been any safety tests required prior to sale that prove that any artificial turf products or rubber playground surfaces are safe for children who play on them regularly, given normal use. In many cases, the materials used are not publicly disclosed, making independent research difficult to conduct. None of these products are proven to be as safe as natural grass in well-constructed fields, or Engineered Wood Fiber for playground surfaces.

Related Articles

NCHR Letter to the DC City Council on Artificial Turf
Risks of Head Injuries on Artificial Turf Fields in Washington, DC
Nearly a Dozen Artificial Turf Fields in DC Failed Last Round of Safety Tests

All articles on our website have been approved by Dr. Diana Zuckerman and other senior staff.

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