title: Leaching of Terbutryn and Its Photodegradation Products from Artificial Walls under Natural Weather Conditions.
abstract: Terbutryn is a commonly used biocide in construction materials. Especially polymer-resin-based renders and paints, used in external thermal insulation composite systems, are very susceptible to microbial deterioration. Previous studies have shown that biocides leach out of the material when contacted with rainwater; thus, they reach surface waters where they might have adverse effects on aquatic organisms. The knowledge on the long-term leaching performance and especially the formation and fate of degradation products is rare. In the present study, the leaching of terbutryn from artificial walls equipped with two types of render was observed for 19 months. In addition to concentration and mass load determinations for terbutryn, photodegradation products were identified and studied in the leachate and render. The results show that terbutryn leached mainly within the first 6-12 months. During the exposure, only 3% of the initial terbutryn was emitted to the runoff, while 64-80% remained in the coating. The overall mass balance could be closed by including several degradation products. Contrary to expectations, the major fraction of transformation products remained in the material and was not washed off immediately, which is of high importance for the long-term assessment of biocides in coating materials.
authors.affiliation: Department of Environmental Science, Aarhus University , Frederiksborgvej 399, 4000 Roskilde, Denmark.
authors.forename: Ulla E
authors.initials: UE
authors.lastname: Bollmann
authors.affiliation: Department of Civil Engineering, Aalborg University , Sofiendalsvej 11, 9200 Aalborg SV, Denmark.
authors.forename: Greta
authors.initials: G
authors.lastname: Minelgaite
authors.affiliation: German Federal Institute of Hydrology , Am Mainzer Tor 1, 56068 Koblenz, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schlüsener
authors.affiliation: German Federal Institute of Hydrology , Am Mainzer Tor 1, 56068 Koblenz, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Ternes
authors.affiliation: Department of Civil Engineering, Aalborg University , Sofiendalsvej 11, 9200 Aalborg SV, Denmark.
authors.forename: Jes
authors.initials: J
authors.lastname: Vollertsen
authors.affiliation: Department of Environmental Science, Aarhus University , Frederiksborgvej 399, 4000 Roskilde, Denmark.
authors.forename: Kai
authors.initials: K
authors.lastname: Bester
mesh_terms: D003252:Construction Materials; D003718:Denmark; D004202:Disinfectants / Q000032:analysis* / Q000737:chemistry; D010150:Paint; D010782:Photolysis; D014227:Triazines / Q000032:analysis* / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry; D014887:Weather
chemical_list: D004202:Disinfectants; D014227:Triazines; D014874:Water Pollutants, Chemical; C010347:terbutryne