Researchers used silicone wristbands to examine the extent of chemical exposure among a small group of children in Montevideo, Uruguay. The 6- to 8-year-olds wore the bands for seven days. After analyzing the wristbands, researchers found an average of 13 pollutants in each one collected. Some of the wristbands showed exposure to DDT, a harmful pesticide that has been banned for use in many countries, including the U.S., since the 1970s.