Respiratory Responses of Mice Exposed to Thermal Decomposition Products from Polymers Heated at and Above Workplace Processing Temperatures

Abstract

Mice were exposed to thermal decomposition products (TDP) released from acrylonitrile butadiene styrene (ABS), polypropylene-polyethylene copolymer (CP), polypropylene homopolymer (HP), or plasticized polyvinylchloride (PVC). These resins were heated in a temperature programmable furnace, at and above workplace processing temperatures. LC₅₀ and RD₅₀ values were obtained on the basis of resin mass loaded in the furnace. LT₅₀ values were determined at the respective LC₅₀ masses. RD₅₀ values were also obtained on the basis of particulate concentrations measured during heating of each resin. The results of this study indicated that PVC and HP were more toxic and faster-acting than wood, while ABS and CP were much more toxic and much faster-acting than wood. At processing temperatures between 200–300°C, RD₅₀ values (based on particulate concentrations) were 21.1, 3.51, 2.60, and 11.51 mg/m³ for ABS, CP, HP, and PVC. Exposure limits of 0.63, 0.11, 0.08, and 0.35 mg/m³ were recommended for TDP of ABS, CP, HP, and PVC to protect workers from their irritating properties. Because there are few, if any, guidelines for recognition, evaluation, or control of TDP, the experimental approach and results of this study should be useful to health and safety professionals.