Ecotoxicological testing of waste materials: State of the art and future developments

In the European Union, the hazard properties of wastes have to be determined according to the Commission Regulation (EU) N° 1357/2014. However, this document does not specify how the HP 14 property (Ecotoxic) has to be tested and assessed. In fact, there are two, approaches for this task: 1. Evaluation according to the CLP-approach, which defines the rules for the classification of chemical mixtures. In that case, the hazard of a waste is calculated according to its chemical composition, based on summation of classified components. The main problem of such an approach is that waste samples usually contain many, often unknown chemicals. 2. Ecotoxicological testing of waste samples, using standard ISO methods originally developed for the assessment of contaminated water or soils. An early version of this approach has successfully been used in an international ringtest. Recently, a strategy that combines both approaches described above has been proposed. The waste assessment starts with the evaluation of existing information on the chemical composition and the summation method is carried out according to the CLP regulation. If sufficient data on the composition are available the assessment can be finalized after this step. Also when the waste is already classified based on partial data, no further assessment is needed. In all other cases ecotoxicological tests have to be performed. First an assessment of the ecotoxicity of the waste eluates using aquatic tests, has to be done. If the waste sample is not classified as hazardous based on its aquatic toxicity, the ecotoxicity of the solid waste material is tested using terrestrial tests. The waste is classified as hazardous or non-hazardous when limit values for hazardous chemicals (in step 1) of for toxicity (in steps 2 and 3) are exceeded or not. Based on experiences of 20 years of waste testing, a test battery has been selected, consisting of three aquatic and three terrestrial tests (per compartment one microbial, one plant and one invertebrate species). Using the approach described so far and using examples from our own research in France, Germany and Belgium we will show that this strategy of combining an initial CLP-classification with ecotoxicological tests as a second step is scientifically sound, practical and easy to perform. However, open research questions still remain (e.g. the identification of threshold values, or the consistency of this assessment with the List of Waste)

Hazard property classification of waste according to the recent propositions of the EC using different methods

International audienceHazard classification of waste is a necessity, but the hazard properties (named "H" and soon "HP") are still not all defined in a practical and operational manner at EU level. Following discussion of subsequent draft proposals from the Commission there is still no final decision. Methods to implement the proposals have recently been proposed: tests methods for physical risks, test batteries for aquatic and terrestrial ecotoxicity, an analytical package for exhaustive determination of organic substances and mineral elements, surrogate methods for the speciation of mineral elements in mineral substances in waste, and calculation methods for human toxicity and ecotoxicity with M factors. In this paper the different proposed methods have been applied to a large assortment of solid and liquid wastes (>100). Data for 45 wastes documented with extensive chemical analysis and flammability test - were assessed in terms of the different HP criteria and results were compared to LoW for lack of an independent classification. For most waste streams the classification matches with the designation provided in the LoW. This indicates that the criteria used by LoW are similar to the HP limit values. This data set showed HP 14 'Ecotoxic chronic' is the most discriminating HP. All wastes classified as acute ecotoxic are also chronic ecotoxic and the assessment of acute ecotoxicity separately is therefore not needed. The high number of HP 14 classified wastes is due to the very low limit values when stringent M factors are applied to total concentrations (worst case method). With M factor set to 1 the classification method is not sufficiently discriminating between hazardous and non-hazardous materials. The second most frequent hazard is HP 7 'Carcinogenic'. The third most frequent hazard is HP 10 'Toxic for reproduction' and the fourth most frequent hazard is HP 4 "Irritant - skin irritation and eye damage". In a stepwise approach, it seems relevant to assess HP 14 first, then, if the waste is not classified as hazardous, to assess subsequently HP 7, HP 10 and HP 4, and then if still not classified as hazardous, to assess the remaining properties. The elements triggering the HP 14 classification in order of importance are Zn, Cu, Pb, Cr, Cd and Hg. Progress in the speciation of Zn and Cu is essential for HP 14. Organics were quantified by the proposed method (AFNOR XP X30-489) and need no speciation. Organics can contribute significantly to intrinsic toxicity in many waste materials, but they are only of minor importance for the assessment of HP 14 as the metal concentrations are the main HP 14 classifiers. Organic compounds are however responsible for other toxicological characteristics (hormone disturbance, genotoxicity, reprotoxicity...) and shall be taken into account when the waste is not HP 14 classified

Results from a round robin test for the ecotoxicological evaluation of construction products using two leaching tests and an aquatic test battery

A European round robin test according to ISO 5725-2 was conceptually prepared, realised, and evaluated. The aim was to determine the inter-laboratory variability of the overall process for the ecotoxicological characterization of construction products in eluates and bioassays. To this end, two construction products BAM-G1 (granulate) and HSR-2 (roof sealing sheet), both made of EPDM polymers (rubber), were selected. The granular construction product was eluted in a one stage batch test, the planar product in the Dynamic Surface Leaching test (DSLT). A total of 17 laboratories from 5 countries participated in the round robin test: Germany (12), Austria (2), Belgium (1), Czech Republic (1) and France (1). A test battery of four standardised ecotoxicity tests with algae, daphnia, luminescent bacteria and zebrafish eggs was used. As toxicity measures, EC50 and LID values were calculated. All tests, except the fish egg test, were basically able to demonstrate toxic effects and the level of toxicity. The reproducibility of test results depended on the test specimens and the test organisms. Generally, the variability of the EC50 or LID values increased with the overall level of toxicity. For the very toxic BAM-G1 eluate a relative high variability of CV = 73%–110% was observed for EC50 in all biotests, while for the less toxic HSR-2 eluate the reproducibility of EC50 varied with sensitivity: it was very good (CV = 9.3%) for the daphnia test with the lowest sensitivity, followed by the algae test (CV = 36.4%). The luminescent bacteria test, being the most sensitive bioassay for HSR-2 Eluate, showed the highest variability (CV = 74.8%). When considering the complex overall process the reproducibility of bioassays with eluates from construction products was acceptable