Hazardous properties of mineral and organo-mineral plastic additives and management of hazardous plastics

Many plastic additives are mineral or organo-mineral substances having functions as pigments, heat stabilizers, flame retardants, process adjuvants and the like. Are additivated plastics hazardous when they become waste? Data from the Plastic Additives Initiative, a joint industry and EU effort, was used, along with substance hazard statements from the ECHA website and hazard properties from the waste classification. 20 elements of 91 substances, namely Al, B, Ba, Bi, Cd, Co, Cr, Cu, F, I, Li, Mn, Ni, Pb, Pr, Sb, Sn, Ti, V and Zn were selected, and their additives used in 11 polymers, considered. Of the 91 substances selected, 57 are non-hazardous or are hazardous but used at too low concentration to render the plastic hazardous when it becomes waste. 34 substances (= 37% of 91) are hazardous and make plastics hazardous as waste. These are mainly heat stabilizers (for PVC), or pigments and flame retardants (for all polymers). The sorting of these plastics by the mineral concentration of their additives with online XRF is theoretically achievable. With data from previous papers, 63 additives (= 27% of 233) make plastic hazardous. The brominated flame retardants are the less documented. Only essential use should be encouraged for pigments. Waste management today should focus on turning waste into non-waste, not waste leakage. With occupational safety and health regulations during processing, and with product regulations during its second life, the material should be managed as another hazardous or non-hazardous (virgin) raw material, and given end-of-waste status when it enters the loop.