Tire crumb is recycled rubber from old tires that is ground up into crumbs. These crumbs are used to make playground surfaces for cushioning under swings, slides and other play equipment. Tire crumbs also are used to make synthetic turf—green plastic grass blades suspended in a thick layer of tire crumb, which looks like soil.
Recycling old tires this way seemed like a good idea because tires aren’t biodegradable and can’t go in landfills. But many experts worry that tire crumb hasn’t been properly evaluated and could be a health hazard for children and student athletes.
Because tire crumb is made from used tires, it probably contains the same chemicals found in tires. Chemicals are added to rubber during the manufacturing process. These may include zinc, sulfur, carbon black and oils that contain polyaromatic hydrocarbons (PAHs).
A Yale University researcher tested tire crumb samples and identified 96 different chemicals. About half of these chemicals had not been evaluated to see if they were health hazards. Of the chemicals that had been tested, 10 to 20 percent can cause cancer. About 40 percent of these chemicals can irritate the respiratory tract. Some can cause asthma.
What’s Being Done
Public concern about the safety of recycled rubber tire crumb used in playground surfaces and playing fields in the US has prompted action by federal agencies. The Environmental Protection Agency (EPA), Centers for Disease Control (CDC), the Agency for Toxic Substances and Disease Registry (ATSDR) and the Consumer Product Safety Commission (CPSC) are currently working to find answers. Scientific information evaluating health risks from tire crumb are limited. To fill this gap in knowledge and data, these agencies are conducting a large study across the US—the first one of its type.
“We are committed to supporting more comprehensive efforts to assess risk from tire crumb,” says the EPA.
The final results of the study, which began in early 2016, are expected to be released this year. Hopefully, it will answer questions about whether children who play on tire crumb surfaces and fields are exposed to these health hazards.
- Chemical Risk. The study is analyzing chemicals found in recycled tire crumb. Because not all tire crumbs are made the same way, they’re testing samples from different manufacturers. Samples have been collected from 40 indoor and outdoor
playing fields and 9 recycling plants.
- Exposure Risk. The study will identify ways in which people can be exposed to tire crumb and associated risks. Children’s skin can come in contact with tire crumb if they fall or slide on the surface. Tire crumb dust can get on children’s shoes or clothes. Some children might swallow tire crumb pieces or dust without meaning to. Chemicals found in tire crumb can be inhaled. To understand the impact of heat, the study will look at exposure during the hottest months of 2017.
How to Protect Your Child
The CPSC recommends taking precautions when your child plays on a surface containing tire crumb. Some commonsense steps are:
- Wash hands after playing on a tire crumb surface and before handling food.
- Clean other areas of exposed skin (in addition to washing hands).
- Don’t eat food or drink beverages while standing or sitting on tire crumb surfaces.
- Clean any toys that come in contact with the tire crumb surface.
- Change clothes if you see signs of tire crumbs, such as black marks or dust.
- Remove and clean shoes contaminated with tire crumb dust before going in the house.
- Keep tire crumb material out of your child’s mouth. Don’t let your child chew on it or swallow it.
- Limit the time your child is on a tire crumb surface on extremely hot days.
- Promptly clean any skin cuts and abrasions to reduce the risk of infection.
For more information, see the “Federal Research on Recycled Tire Crumb Used on Playing Fields” on the EPA website.
Brenda Schoolfield is a freelance medical writer who splits her time between Austin and Seattle.