Biocides in antifouling paint formulations currently registered for use.

César Augusto Paz-Villarraga,Ítalo Braga Castro,Gilberto Fillmann

doi:10.1007/s11356-021-17662-5

Abstract

Antifouling paints incorporate biocides in their composition seeking to avoid or minimize the settlement and growing of undesirable fouling organisms. Therefore, biocides are released into the aquatic environments also affecting several nontarget organisms and, thus, compromising ecosystems. Despite global efforts to investigate the environmental occurrence and toxicity of biocides currently used in antifouling paints, the specific active ingredients that have been used in commercial products are poorly known. Thus, the present study assessed the frequencies of occurrence and relative concentrations of biocides in antifouling paint formulations registered for marketing worldwide. The main data were obtained from databases of governmental agencies, business associations, and safety data sheets from paint manufacturers around the world. The results pointed out for 25 active ingredients currently used as biocides, where up to six biocides have been simultaneously used in the examined formulations. Cuprous oxide, copper pyrithione, zinc pyrithione, zineb, DCOIT, and cuprous thiocyanate were the most frequent ones, with mean relative concentrations of 35.9 ± 12.8%, 2.9 ± 1.6%, 4.0 ± 5.3%, 5.4 ± 2.0%, 1.9 ± 1.9%, and 18.1 ± 8.0% (w/w) of respective biocide present in the antifouling paint formulations. Surprisingly, antifouling paints containing TBT as an active ingredient are still being registered for commercialization nowadays. These results can be applied as a proxy of biocides that are possibly being used by antifouling systems and, consequently, released into the aquatic environment, which can help to prioritize the active ingredients that should be addressed in future studies.

Highlights

Antifouling paints have been used to prevent the settlement of fouling in vessel hulls(Omae 2003; Dafforn et al 2011), aquaculture facilities (Guardiola et al 2012) and other submerged structures, such as pipes, gates, stationary structures, etc (Bleile and Rodgers 2001; Yebra et al 2004; Claudi and de Oliveira 2015)
These results can be applied as a proxy of biocides that are possibly being used by antifouling systems and, released into the aquatic environment, which can help to prioritize the active ingredients that should be addressed in future studies
Despite only partially reflecting the current general situation, such findings can be applied as a proxy of biocides that are possibly being used by antifouling systems and, released into the aquatic environment

Summary

Introduction

Antifouling paints have been used to prevent the settlement of fouling in vessel hulls(Omae 2003; Dafforn et al 2011), aquaculture facilities (Guardiola et al 2012) and other submerged structures, such as pipes, gates, stationary structures, etc (Bleile and Rodgers 2001; Yebra et al 2004; Claudi and de Oliveira 2015). Except in biocide-free antifouling paints, all other technologies contain one or more biocides in their composition. In these products, the films covering submerged structures act as a source of biocides to the aquatic environments, which may partition on different environmental matrices and cause deleterious effects to the aquatic organisms (Amara et al 2018). New chemicals, such as tralopyril (Kempen 2011) and medetomidine (I-Tech AB 2020), have been introduced seeking for more environment friendly and effective antifouling paints (Faÿ et al 2019)

Methods

Results

Conclusion