Compliance of brown mussel (Perna perna) production areas in the South of Brazil with the bacteriological criteria of the shellfish hygiene systems in the European Union and United States of America: assessing the impacts on consumer safety.

Levels of faecal indicator organisms (FIOs) monitored in surface water and brown mussels collected at 28 production areas in Brazil from August 2012 to October 2013 were used to assess compliance with the bacteriological standards of the shellfish hygiene classification systems used in the European Union (EU) and USA. This classification determines the level of post-harvesting purification needed to reduce the risk of illness in consumers. The results indicate that 36% of production areas would be class A under the EU system and 75% would be 'Approved' under the US system. Mathematical models showed that a 90th percentile of FIO levels in water of 43 MPN (most probable number) 100 mL (standard for 'Approved' areas under the US system) would correspond to an 80th percentile of FIO levels in mussels of 572 MPN 100 g. This concentration is more than double that in the class A standard in the EU system. These results have important implications for public health since no post-harvesting purification is required for any of these classification categories. Areas compliant with the US 'Restricted' and EU class B standards, however, provide similar levels of consumer safety.