Thousands of playgrounds and sports fields around the country have been covered with crumb rubber from recycled tires, and some experts and lawmakers are concerned about possible health effects on children. Dr. Homero Harari, with the Institute for Exposomic Research at Mount Sinai in New York, spoke to The Guardian about the chemicals found in used tires. “The main concern is that there was a lack of safety testing prior to the introduction of the material in playing surfaces,” Harari said. “As scientists, we normally apply the precautionary principle – when we know that there’s concern about a substance or chemical, we normally try to avoid it.” Crumb rubber often breaks apart, spreading into the air children breathe and getting swallowed when kids put their hands in their mouths. To read the full article click here.