At the open burning sites, some metals were present at concentrations over one hundred times typical background levels for soils, including lead, a highly toxic metal. High levels of other toxic metals, including cadmium and antimony, were also present. Numerous classes of organic chemicals were also present in one or more of the samples, including many halogenated (chlorinated or brominated) chemicals. Many of the compounds identified are intentionally used in electronic devices. These included phthalates, widely used as plasticisers in flexible plastics such as PVC, polybrominated diphenyl ethers (PBDEs) and triphenyl phosphate (TPP) both used as flame retardants, and polychlorinated biphenyls (PCBs) , long banned from.
