Toxic Crumb Rubber: The Dangers Below our Children’s Feet

Welcome back to the GPL Blog.  This month we’ve been talking about toxicity and how the Great Plains Laboratory can help you assess toxic burden.   This week I thought I would talk about a topic that has been getting quite a bit of publicity lately and that is the use of ground up rubber tires for playgrounds and sports fields.

In the last two decades, many playgrounds, soccer fields, and football fields have been replacing their natural surfaces with a synthetic surface of rubber granules made up of ground tires.  Despite the popularity of these types of surfaces many different activist groups have expressed concern that these synthetic materials may be a toxic burden on our children.

In 2006 a commentary was written in Environmental Health Perspectives detailing how little we knew about the material we are having our children play on (Anderson et al, 2006).  In the years since, there have been some insightful studies performed that give clues into how harmful prolonged exposure to these rubber play areas may be.  In 2007, a study from the nonprofit organization Environment and Human Health, Inc. and the Department of Analytical Chemistry at the Connecticut Agricultural Experimental Station produced one of the first reports about chemicals found leaching from artificial surfaces made from rubber tires.  This report indicated that benzothiazole, butylated hydroxyanisole, n-hexadecane, 4-(t-oxtyl) phenol, and zinc was found leaching from the tires.  These chemicals are known carcinogens and neurotoxicants (Brown et al., 2007).

A second report in 2008 in the Journal of Exposure Science and Environmental Epidemiology provided some additional data on the chemicals that could affect children.  The report indicated that the rubber granules have a much higher amount of polycyclic aromatic hydrocarbons (PAHs) than soil.  Zinc and chromium were also found to be much higher in the artificial surfaces than in soil.  The report also stated that although lead was not found to be much higher than in soil the bioaccessibility was much higher (Zhang et al, 2008).  PAHs are known neurotoxic chemicals which have been found in air pollution from fossil fuel combustion.  A recent study published in PLOS One from the University of Columbia discovered a link between PAH exposure and the development of attention deficit and hyperactivity problems (Perera et al., 2014).

So how can we determine if our children are being exposed to these chemicals?  The GPL-TOX profile has two markers that can be used to measure chemicals commonly leached from tires.  These two markers are N-acetyl (3,4-dihydroxybutyl) cysteine (whose parent is 1,3 butadiene) and Phenylglyoxylic acid (whose parent is styrene).   The presence of 1,3 butadieneand styrene in urine have been linked to rubber exposure.  I also recommend doing a hair metals test.  USA Today reported in 2015 that “lead levels high enough to potentially harm children have been found in artificial turf used in thousands of schools, playgrounds and day-care centers.”  By utilizing the GPL-TOX profile and the hair metals test you should be able to determine the amount of tire chemicals your child has absorbed.

In two weeks I will be talking about the detoxification pathways that the body uses to get rid of toxins, and the following week I will discuss which detoxification methods seem to be delivering the best results.  I have been working with several doctors to help develop methods.  I will provide some GPL-TOX results from patients’ pre and post detoxification. 


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