O CONAMA e os poluentes emergentes: um estudo de caso sobre a Resolução 357 e os anti-incrustantes marinhos

Abstract

Shipping is the most cost-efficient method of international transport for most goods, is reliable, and the low cost facilitates trade and helps create prosperity between peoples and nations. The global fleet of ships provides not only transport connectivity for global trade but also means of subsistence for those working in maritime enterprises in both developed and developing countries. However, despite all the technology surrounding naval activity, there is a problem that continues without a solution both environmentally and economically, biofouling. The economic costs caused by biofouling in the hulls of vessels was the driving force behind the development of technologies used as antifoulings. This is a global industry that drives a billion dollars market every year. Tributyltin (TBT) was the most effective substance in protecting ship's hulls, however, the release of this compound began to cause deleterious damage to non-target species. TBT was then replaced by other antifoulings which should not have any effect on the non-target biota. The banning on the use of TBT was decided by the IMO in 2001, and enforced by September 2008. Faced with this environmental problem, this study aimed to evaluate the Brazilian environmental legislation, in this case, the CONAMA Resolution 357, against marine antifouling in saline and brackish waters, considering both isolated compounds and considering mixtures in five pre-established scenarios. according to the type of maritime activity. There is much available data on antifouling toxicity so that the methodological approach proposed in this paper sought to use data already published in indexed journals to perform the proposed evaluation. Effect Concentrations of the most sensitive species and the average concentration of each antifouling measured in seawater were used to calculate the toxicological units (TU) in each scenario. The results showed that the ban on the use of TBT was a wise decision by IMO since all mixtures in which TBT was present were considered toxic or highly toxic in all scenarios where it was possible to simulate mixtures (binary, ternary and possible quaternary). Substitute compounds to TBT also showed toxicity, although this is lower than the toxicity demonstrated by TBT, and are a less harmful option for aquatic species. Irgarol 1051 being the most toxic, followed by Seanine and Chlorothalonil being the least toxic substance. All mixtures in which Irgarol was present were considered toxic or highly toxic. CONAMA resolution 357 is outdated according to toxicity data and does not include other biocides used in antifouling paints.