Biocide release measurements

Biocide release rate methods were first developed for TBT-containing compounds in an effort to establish limits on their release from AF into marine bodies (Haslbeck and Holm, 2005). The core idea of this kind of methods is to develop standardised procedures which can tell, after as short an experimental time as possible, whether an AF coating will be leaching environmentally acceptable amounts of biocide into sea water. Two such methods are available to measure the release rate of copper, namely the ASTM D6442 and ISO 15181 -... 

Another way to measure the efficiency of a biocidal surface is by detection of the ATP bioluminescence of the adhering microbial cells [18], With this elaborate method, the killing rate of a surface can be measured and it is possible to distinguish between growth inhibition and killing. However, the method does not distinguish between release and contact activity. In general, there is no test that can clearly tell the difference between a contact-active and a release system. 

These assumptions are based on extensive experience within the paint industry of the measured release rates of copper and tin biocides from organotin copolymer and first generation TBT-free antifouling paints. 

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