Hazard classification of waste : review of available practical methods and tools

Abstract

Hazard classification of waste is useful for the sound management and the recycling of potential resources. According to EU, the chemicals and waste policy areas are now converging, since the point is to minimise the adverse effects on human health and the environment, by phasing out hazardous chemicals or reducing release to air, water and soil. An exhaustive analysis of elements and substances and some tests are required to prove that a waste is non-hazardous. This can help to identify substances of concern not clearly evidenced by the waste management community. Many of these substances were legally used when the products were manufactured, but when the products become waste and are recovered, the now banned or restricted substance may still be contained in the recovered material. This classification can be used to improve the recycling of resources and to avoid dispersion of hazardous elements or substances during uncontrolled use (avoiding loops of hazardous substances). Some hard examples are plastics products with low concentration of antimony and brominated flame retardants from recycled plastics, concrete blocks with granulate of lead activated glass from cathode ray tubes, or dike reinforcement by sand and gravel from copper and lead slags. The different steps for classification are collection of information, sampling, analysis, tests, hypothesis of speciation of elements into mineral substances, collecting hazard statement codes of substances, and comparing weighted sum or maxima of concentrations or tests results with given concentration limits for each hazard property, or eventual use of now available internet sites, will be presented.