Proposed method for verification of D2 BWM standard (IMO, 2004) when the presence of toxigenic V. cholerae

Abstract

Bioinvasion by ballast water is intensified by the globalization process, which causes an increase in maritime transport. The growing commercial exchange between countries, through maritime transport, determines an increase in the fleet of vessels, increasing the volume of ballast transported. Therefore, verifying the effectiveness of discarded ballast water treatment methodologies becomes a challenge for port authorities. The Ballast Water Management (BWM) Convention (IMO 2004) sets standards for ballast management, specifying the maximum number of microorganisms of health relevance permitted for disposal. Among this Vibrio cholera (O1 and 139), which causes cholera, stands out. The study aims to describe and validate a proposal for risk classification and selection of vessels to verify compliance with the D2 standard of the BWM 2004 Convention, thus filling a gap with regard to the problem. 3,350 visits were monitored at the port of the city of Rio de Janeiro (Brazil) between 2016 and 2018. After classifying the vessels, 67 (2%) were described as priority for standard verification. The significant reduction in the number of vessels to be verified, with the proposed methodology, contributes to the feasibility of applying the D2 standard, thus reducing the sampling effort.