I have always enjoyed the aesthetics of a wooden playground over metal and plastic play structures, but in order for the wood to hold up to the elements, it is treated with chemicals that are toxic. The Safe Playgrounds Project explains:
Arsenic-treated wood has been used to build many outdoor structures such as decks, picnic tables and play equipment. Chromated-copper arsenate (CCA) was widely used over the last thirty years as an insecticide and preservative in pressure-treating wood for outdoor structures. Of the 3 chemicals (arsenic, copper and chromium), arsenic is considered the most toxic.
Arsenic causes cancer and other serious health risks. Arsenic is a far more potent skin, bladder, and lung carcinogen than previously thought. It is also linked to suppression of the immune system, cardiovascular disease, and diabetes.
Although the EPA and wood products industry has mutually agreed to phase out CCA lumber in residential applications, this toxic lumber remains in our homes and playgrounds. Pressure-treated lumber often has a greenish tinge to it from the chemicals injected into it to preserve the wood.
Unfortunately, many older playgrounds still exist and the CPSC has refused to completely ban CCA lumber, even though CPSC staff scientists found that some children may face an increased risk of developing lung or bladder cancer from playground equipment made from CCA wood.
Children come in contact with arsenic residue from hand to the mouth after playing on CCA pressure-treated wood playground equipment. The Environmental Working Group reports:
We know that arsenic in drinking water is dangerous for children, but what we found was that the arsenic in lumber is an even greater risk. In less than two weeks, an average five-year-old playing on an arsenic-treated playset would exceed the lifetime cancer risk considered acceptable under federal pesticide law.
A new study published in the journal Environmental Science & Technology contradicts these findings. According to the study’s abstract:
Children may be exposed to arsenic during contact with structures treated with chromated copper arsenate (CCA). A high frequency of hand-to-mouth activity may increase their risk of ingesting arsenic. Previous work showed that arsenic concentrations in the hand-wash samples of children playing on CCA playgrounds were four times higher than those playing on non-CCA playgrounds. It is not clear whether playing on CCA playgrounds results in elevated overall exposure to arsenic. The objective of this study was to perform arsenic biomonitoring in children to determine whether playing on CCA-treated playgrounds substantially contributes to their overall exposure to arsenic. One hundred and twenty five saliva samples from 61 children and 101 urine samples from 45 children were collected after children played on 8 CCA and 8 non-CCA playgrounds. Arsenic speciation analysis was conducted using high performance liquid chromatography combined with inductively coupled plasma mass spectrometry. The arsenic species detected in the urine and saliva samples from children playing on CCA and non-CCA playgrounds were similar. These results show that there is no significant difference in the concentration or speciation of arsenic between the samples from children playing on CCA and non-CCA playgrounds. Contact with CCA playgrounds is not likely to significantly contribute to the overall arsenic exposure in children; other sources such as dietary arsenic may be a main contributor to their overall exposure.
It is scary to consider dietary arsenic is to blame for children’s exposure, and I know that it occurs naturally in our local water. Although this study found “no significant difference” between CCA and non-CCA playgrounds, I still do not want to risk my children playing on these toxic structures. Furthermore, pressure-treated lumber manufacturing sites are huge sources of pollution and some are classified as superfund sites.
I’d like to see a more comprehensive, long-term study completed with a larger sampling, and I hope the results of this study are not used to avoid protecting our children from pressure-treated lumber. Hopefully, the results will cause further investigation of the dietary sources, which I suspect could be from CCA lumber leaching into drinking water and agricultural irrigation sources.