I would like to replace my polycarbonate Nalgene bottle or kids sippy cup with a SIGG bottle, but why are SIGG caps made from plastic?
All SIGG bottle caps are made from Polypropylene (#5) – an FDA approved, food safe plastic. This type of plastic will not transfer any harmful substances into the bottle’s contents. Some Nalgene bottles and many kids sippy cups are made with Polycarbonate (#7). Also known as LEXAN, studies have shown that this plastic may leach bisphenol-A (BPA), a chemical that mimics the hormone estrogen. “For years, scientists have been finding that endocrine disrupters like BPA can impair the reproductive organs of rats and mice, reduce sperm counts in rats, and bring about changes in tissue that resemble early-stage breast cancer, among other effects… Normal wear-and-tear and cleaning of polycarbonate plastic bottles in a dishwasher, Hunt says, could cause the chemical to leach, and the amount of leaching increases as the plastic ages and is degraded by use. A separate study published in July in Environmental Health Perspectives confirmed this finding, and also detected leaching from new polycar
