Toxicity and Preliminary Risk Assessment of Alternative Antifouling Biocides to Aquatic Organisms

Abstract

Published literature has been reviewed regarding the toxicity of representative alternative antifouling biocides (Chlorothalonil, Dichlofluanid, Diuron, Irgarol 1051, Sea Nine 211, TCMTB, Zineb, ZnPT, CuPT and PK) in aquatic environments, and their hazardous impact on aquatic environments has been evaluated using the information obtained during the process of review. The following statements represent the conclusions. Acute toxicities of the alternative antifouling biocides are in a range of ₅₀ to ₅₀. Irgarol 1051 exhibits especially high toxicity to phytoplankton and seaweed. On the basis of these toxicity values the biocides are classified as “toxic to very toxic” by the OECD classification guidelines. The acute toxicity value of M1, which is a degradation product of Irgarol 1051, ranges between t and s. M1 is also classified as “toxic” to “very toxic” by the OECD classification guidelines. The toxicity levels of these alternative antifouling biocides are almost the same as TBT. The reported concentrations of Irgarol 1051, M1, and Sea Nine 211 exceed the respective PNEC values especially in marinas and fishery harbors implying that Irgarol 1051, M1, and Sea Nine 211 are already causing a hazardous impact on the aquatic ecosystem in some marinas and fishery harbors. In order to assess the ecotoxicological risk of these biocides in detail, further research to clarify the toxicity and to develop the methods of estimating concentrations in natural waters are needed.