Speaker: Ute Schoknecht, BAM, Bundesanstalt für Materialforschung und -prüfung
(guest of Kai Bester, MITO)

Title: Characterisation of leaching of biocides from treated materials

Abstract: Marketing of biocidal products in Europe is regulated by the Biocidal Products Regulation (EU) No. 528/2012. Environmental risk assessment is integral part of the authorization procedure. Biocides can be released from materials into water and soil during service life due to contact with water. Risk assessments require estimations of input of biocides into environmental compartments for defined periods of time. This needs harmonised test methods and procedures to interpret test results.

Test methods for treated articles were proposed and tested during a current research project at BAM in cooperation with project partners.

The proposed laboratory test proved to be suitable and repeatable for a series of active substances and materials. Leaching under field conditions is a discontinuous process that depends on complex exposure conditions. Several parameters can have opposed effects on leaching processes. Cumulative data enable simplifications, and repeatability is improved if emission data are related to the amount of precipitation or runoff volume.

Both laboratory and field tests describe material properties, i.e. leaching potential of substances. Emissions are roughly related to physicochemical properties of active substances and depend on product properties. Gaps in mass balances indicate further processes, i.e. degradation and evaporation. Ratios between emissions in laboratory and field tests depend on properties of materials and target substances. Application of laboratory test data for risk assessments requires experiences from field tests or service conditions for each type of material.

Language: English