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New Study – Many carcinogens found in Yale analysis of crumb rubber infill and playground mulch surfacing

North Haven, Conn., June 11, 2015—Environment and Human Health, Inc. (EHHI), an organization of physicians and public health professionals, is releasing its study done at Yale University showing that the analysis found 96 chemicals in the rubber tire infill used in synthetic turf and rubber tire mulch used as surfacing in toddler playgrounds.

Of the 96 chemicals detected – a little under a half have had NO toxicity assessments done on them for their health effects - therefore nothing is known about them. The other half have had SOME toxicity testing done on them - but even many of those chemicals had incomplete toxicity testing and therefore all health effects are not fully known.

Of the half that have had toxicity assessments, 20% are probable carcinogens.

As well, 40% of the chemicals in that group were found to be irritants. 24% are respiratory irritants - some causing asthma symptoms; 37% are skin irritants; and 27% can cause eye irritants.

Gaboury Benoit, Ph.D., Yale Professor of Environmental Chemistry and Engineering and lead investigator of the study said, "Not surprisingly, the shredded tires contain a veritable witches brew of toxic substances. It seems irresponsible to market a hazardous waste as a consumer product."

David Brown, Sc.D. Public Health Toxicologist explained that, “Chemicals are usually assessed for their toxicity one chemical at a time. Synergistic affects of being exposed to numerous chemicals at the same time is not known. From the data of this new study, it is reasonable to assume that persons playing on synthetic turf fields with rubber tire infill or toddler playgrounds surfaced with rubber tire mulch are being exposed concurrently to multiple chemicals.”

The 96 chemicals were found in the 14 samples analyzed. Each sample represented either a different synthetic turf supplier or a different unopened bag of rubber playground mulch.

The shredded rubber tire playground mulch samples tested were provided by the manufacturer and were purchased in new bags of rubber mulch for use in gardens and playgrounds. The rubber tire infill for synthetic turf fields was obtained as new infill material from installers of synthetic turf fields. There were 5 samples of infill from 5 different installers of fields and 9 different samples of rubber mulch taken from 9 different unopened bags of playground mulch.

This study did not analyze for the carbon black that makes up to 30% of each tire, nor did it analyze the carbon black nanoparticles or the nanotubes that are now used in the manufacture of tires. The study also did not test for heavy metals. It is known from other studies that rubber tires contain large amounts of zinc.

These additional substances add to the toxicity of the shredded rubber tires that are presently used in both synthetic turf fields and toddler playgrounds.

“This study should give pause to all those schools, towns, and government agencies that have told the public these fields are safe,” said Nancy Alderman, President of Environment and Human Health, Inc. Exposing toddlers, students and athletes to this many chemicals, many at the same time, seems like incredibly irresponsible experiment in people’s health and needs to come to an abrupt end.

Environment and Human Health, Inc. (EHHI), is a non-profit organization composed of physicians, public health professionals and policy experts, dedicated to protecting human health from environmental harms. EHHI does not receive any funds from businesses or corporations.

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