Risk assessment of leaching of substances from synthetic polymeric matrices (original) (raw)

Risk assessment of leaching of substances from synthetic polymeric matrices The leaching of substances from plastics is fundamentally different from leaching of substances from, for example, stony materials. However, the current environmental risk assessment of building materials has been derived for stony materials and does not account for ageing and wheathering of the material. These processes have higher rates in plastics and have an high impact on the leaching of substances. To obtain more knowledge about ageing and wheathering it is necessary to develop a specific testing strategy for plastics. This follows from a literature study of the RIVM , commissioned by the Ministry of Housing, Spatial Planning and the Environment. Plastics, or synthetic polymeric matrices, contain unknown by-products and many additives, for example pigments, softeners, flame retardants and antioxidants, which are distributed in the environment when exposed to water. Bioassays are recommended as additional test to account for the environmental risk of exposure to cocktails of known and unknown substances. Bioassays are tests with living aquatic organisms and provide information about the effects of unknown substances or combinations of substances. The use of plastics or recycled plastics for outdoor purposes is increasing. Yet, the knowledge about the identity and quantity of leached substances stays behind. The European Committee for Standardization (CEN) aims at harmonization of test and risk assessment methods for different building materials, such as stone, wood, metal and plastics. This aim is based on the assumed similarity of leaching mechanisms.