title: Influence of leaching conditions for ecotoxicological classification of ash.
abstract: The Waste Framework Directive (WFD; 2008/98/EC) states that classification of hazardous ecotoxicological properties of wastes (i.e. criteria H-14), should be based on the Community legislation on chemicals (i.e. CLP Regulation 1272/2008). However, harmonizing the waste and chemical classification may involve drastic changes related to choice of leaching tests as compared to e.g. the current European standard for ecotoxic characterization of waste (CEN 14735). The primary aim of the present study was therefore to evaluate the influence of leaching conditions, i.e. pH (inherent pH (∼10), and 7), liquid to solid (L/S) ratio (10 and 1000 L/kg) and particle size (<4 mm, <1 mm, and <0.125 mm), for subsequent chemical analysis and ecotoxicity testing in relation to classification of municipal waste incineration bottom ash. The hazard potential, based on either comparisons between element levels in leachate and literature toxicity data or ecotoxicity testing of the leachates, was overall significantly higher at low particle size (<0.125 mm) as compared to particle fractions <1mm and <4mm, at pH 10 as compared to pH 7, and at L/S 10 as compared to L/S 1000. These results show that the choice of leaching conditions is crucial for H-14 classification of ash and must be carefully considered in deciding on future guidance procedures in Europe.
authors.affiliation: Department of Applied Environmental Science (ITM), Stockholm University, SE-106 91 Stockholm, Sweden. Electronic address: sara.stiernstrom@itm.su.se.
authors.forename: S
authors.initials: S
authors.lastname: Stiernström
authors.affiliation: Swedish Geotechnical Institute (SGI), Linköping SE-581 93, Sweden.
authors.forename: A
authors.initials: A
authors.lastname: Enell
authors.affiliation: Swedish Geotechnical Institute (SGI), Linköping SE-581 93, Sweden.
authors.forename: O
authors.initials: O
authors.lastname: Wik
authors.affiliation: Swedish Geotechnical Institute (SGI), Linköping SE-581 93, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Hemström
authors.affiliation: Department of Applied Environmental Science (ITM), Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: M
authors.initials: M
authors.lastname: Breitholtz
mesh_terms: D000818:Animals; D060729:Coal Ash / Q000032:analysis* / Q000145:classification* / Q000633:toxicity; D033342:Copepoda / Q000187:drug effects*; D054750:Ecotoxicology / Q000379:methods; D006256:Hazardous Waste / Q000706:statistics & numerical data*; D006863:Hydrogen-Ion Concentration; D010316:Particle Size; D018709:Statistics, Nonparametric; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D060729:Coal Ash; D006256:Hazardous Waste; D014874:Water Pollutants, Chemical
keywords: Ash; CLP Regulation; Ecotoxicity tests; H-14 classification; Hazardous waste; Waste Framework Directive