Antifouling Paint Residues in Areas Under the Influence of Maritime Activities Along the Brazilian Coast

Abstract

Contamination by antifouling biocides (TBT, DBT, MBT, diuron, Irgarol, chlorothalonil, dichlofluanid, and DCOIT) and antifouling paint particles was assessed in sediments under the influence of maritime activities along the Brazilian coast: Marajó and Guajará Bay (Pará - PA), São Marcos Bay (Maranhão - MA), Fortaleza coast (Fortaleza - CE), Suape and Capibaribe Estuary (Pernambuco - PE), Guanabara Bay (Rio de Janeiro – RJ), Itajaí-Açu Estuary (Santa Catarina - SC), and Patos Lagoon Estuary (Rio Grande do Sul - RS). The relatively low levels of butyltins (BTs) in sediments associated with commercial ports (mean of 26 ng Sn g-1), in addition to butyltin degradation indexes pointing to legacy TBT inputs, confirm the effectiveness of the IMO Antifouling Systems Convention. However, hotspots and recent inputs of TBT were observed at boatyards due probably to the presence of antifouling paint particles (APPs). Booster biocides (BB), although in lower concentrations (mean of ΣBB - 13.7 ng g-1) than BTs (mean of ΣBTs - 126 ng Sn g-1), were also predominant near marinas. DCOIT was the most frequent BB, reflecting its current use in antifouling paints. Moreover, APPs emerge as a relevant source of contamination due to high associated concentrations of antifouling biocides (i.e., DCOIT – 43,139 ng g-1; TBT – 311,474 ng Sn g-1). Several sites presented concentrations above safe values that potentially trigger effects on organisms. In summary, contamination by antifouling biocides is widespread along the Brazilian coastal areas under the influence of maritime activities. Thus, environmental and governmental agencies must act and seek regulatory and protective measures to reduce potential risks to aquatic organisms.

Keywords: Butyltins, Booster biocides, sediment, Maritime activities, Risk Assessment