When I had my first child, one of the things I wanted to add to our outdoor space was a sandbox. I have fond childhood memories of playing in the sand, dirt and mud and wanted that experience for my children. So, I started my research. First, the sandbox. Some options: a naturally weather-resistant FSC-certified sandbox from Pottery Barn Kids or a composite plastic timbers sandbox made from recycled materials. I’ve learned to avoid sandboxes made with pressure-treated wood. According to the Environmental Working Group (EWG), “Many are made of wood preserved with chromated copper arsenate (CCA), the basis of which is arsenic, a carcinogenic chemical that can leach out of CCA-treated wood onto children’s hands and into soil and groundwater.” Next, the sand. This was a little more complicated than I imagined. I thought you could just go to a store and pick up some sand. Boy, was I off base. As I soon discovered, most play sand contains crystalline silica and traces of tremolite. The Occupational Safety and Health Administration (OSHA) explains, “Crystalline silica is a basic component of soil, sand, granite, and many other minerals. Quartz is the most common form of crystalline silica. Cristobalite and tridymite are two other forms of crystalline silica. All three forms may become respirable-size particles when workers chip, cut, drill, or grind objects that contain crystalline silica.” So, is it OK for a sandbox to be, well… dusty? The OSHA goes on to explain the health concerns: “Crystalline silica has been classified as a human lung carcinogen. Additionally, breathing crystalline silica dust can cause silicosis, which in severe cases can be disabling, or even fatal. The respirable silica dust enters the lungs and causes the formation of scar tissue, thus reducing the lungs’ ability to take in oxygen. There is no cure for silicosis.” Crystalline silica has been deemed a human carcinogen by the International Agency for Research on Cancer. In California, there is a warning label on play sand that contains crystalline silica. Add to that the fibrous mineral tremolite, which is a form of the human carcinogen asbestos, and you have an extremely toxic play environment. Not what I had in mind for my little girls. According to the EWG, there are a few things you can do:
- Test your local playground’s sand for asbestos; find a lab through the EPA’s asbestos info line: (202) 554-1404.
- In home sandboxes, avoid “all-purpose” sand, which has not been washed to screen out breathable particles. Safe Play Sand sells asbestos- and silica-free sand. Replace sand regularly to avoid contamination.
- In indoor sand tables, use beans or rice instead of sand — not great for molding, but nice for pouring, measuring or bulldozing.
- If a wooden play structure has a greenish tinge, it has almost certainly been treated with copper, if not CCA. Test wood and soil for arsenic with a kit like the Arsenic Quick Wood Field Testing Kit ($26); treated wood should be sealed every six months with water-based sealants, like those from AFM, or latex paint. And always wash children’s hands after they have been playing on any wooden structure, particularly before eating.