Assessment of Dangerous Substances Release from Construction Products to Environment

Abstract

In 2005 the European Commission mandate CEN to prepare test methods with which construction products can be tested with respect to the potential release of dangerous substances to water, soil and to indoor air. A horizontal approach is considered the best route for such test development. Horizontal approach means that it is product independent and consists of the development of a test method applicable for different products used in a certain scenario. This action will satisfy the needs resulting from Essential Requirement n° 3, on Hygiene, Health and Environment, as specified in the Construction Products Directive. In this context, the aim of the work presented here is to study the release mechanisms and the parameters which could influence the leaching of pollutants from construction products towards soil and water, in order to provide information for the development of a horizontal test. The research has been carried out on monolith products, based on three types of matrices: concrete, wood and metal (zinc). For the concrete products, one of the choice criteria was the presence of trace metals (e.g. chromium VI); the wood products are pertinent candidates for our study because of the preservation treatment, which by definition is toxic for some form of life (biocidal substances are used for the treatment); as for the zinc based products, research on contributions of the different sources of urban run-off pollution, showed a very high concentration of zinc (up to 6 mg/L in a catchment in Paris) in roof run-off. Also, this source represents a very high percentage among other urban run-off pollution sources (92% from roof vs. 8% from yard and street run-off).