Larsen, M.M., Jakobsen, H.H., Göke, C., Hendriksen, N.B., Rømer, J.K., Mohn, C. & Schultz, A.C. 2017. Sanitary survey rapport 3: Venø Bugt, Kås, og Salling. Aarhus Universitet, DCE - Nationalt Center for Miljø og Energi, 138 s. Teknisk rapport fra DCE - Nationalt Center for Miljø og Energi nr. 104.
http://dce2.au.dk/pub/TR104.pdf
According to the Control Regulation for food products of animal origin (Europa Parlamentets og Rådets Forordning (EF) Nr. 854), microbiological classification of production areas for clams etc.[1] and the associated sampling plan are required to be based on so-called ‘sanitary surveys’. A sanitary survey is an assessment of the interactions between potential sources of microbial pollution, climate conditions and oceanography in the area. The EU Commission guidance for making a sanitary survey formed the basis for this report. However, in certain cases, the Danish practice for microbiological sampling frequency and classification made previously on the basis of this, as described in ‘muslingebekendtgørelsen’ is summarized in Appendix 13.
The report covers production areas P5, P6, P7, P8, P9, P11, P12, P13, P14 and P15. For editorial reasons, the production areas are regarded under one term ‘South of Mors’, knowing that the production areas also include other bordering geographical areas. The covered production areas south of Mors are marked with wide blue lines on the figures.
The report recommends a microbiological sampling plan consisting of recommended selected sampling points and sampling frequencies for individual production areas. It is discussed whether merging of production areas into fewer production areas could be considered in the future. The homogeneity in hygiene within each area has been evaluated to determine whether joint monitoring and classification covering mussels from both line and bottom can be justified, or if it should continue to be carried out separately. These changes would then reduce the number of sampling points without compromising food safety.
The report is supported by public accessible data from monitoring of microbiological contamination south of Mors, where the concentration of E. coli is determined in samples of mussels, etc. taken at fixed sampling points.
The Danish mussel monitoring offers generally a solid set of historical data of E. coli concentrations in bivalve shellfish collected from the positions where shellfish have been harvested in the past within the areas south of Mors. The key data set used is a compilation of the date obtained from the production areas during the past 10 years (2007-2016) in the fishermen’s self control and in the Food Authorities Control Program of this. Within this data set, 97 % of a total of 2,354 samples contained E. coli at A level (<230 E. coli/100 g), and 0,5 % of a total of 785 samples contained Salmonella.
In summary, the sanitary survey of south of Mors identifies an area that in general is a microbial homogeneous, stable and microbiologically clean area, and only rare occurrence of critical microbial contamination was found.
Based on an assessment of sources and transport routes for microbiological contamination (sanitary survey) verified against historical microbiological data from south of Mors, a recommended microbiological monitoring programme is recommended for each of the production areas south of Mors.
In each of the recommended monitoring programmes, proposals for a sampling point, classification status (preliminary or permanent) and a sampling plan are outlined.
Based on the results from the sanitary survey of the producing areas, supported by the historical data set of the number, frequency and E. coli concentration in samples, the production area P9 was deemed suitable for permanent classification with a proposed future sampling frequency of at least 12 samples per year over a continued period of three years. The areas P5, P12-P15 were suggested for restricted permanent classification, with proposed analyses of minimum 8 samples per year distributed prior (minimum four weeks) to and during the harvesting periods. Finally, P6-P8 and P11 remain unclassified due to lack of data in 2016 (P6-P7 and P11) and/or due to too few samples (P6-P8) of historical data during the past three years. For these areas to be evaluated for permanent classification, analyses of 12 samples per year (1 per month) was proposed until sample number and frequency compile to initial classification, or contain at least 24 samples over the latest three-year period, to be evaluated for full classification.
The report is divided into main chapters that provide a summary of identified microbiological contaminants. The main chapters take the starting point in appendix 2-10. Appendix 11 is a detailed review of all historical microbiological data from bivalve shellfish monitoring consisting of the fishery’s self-control and the Danish Veterinary and Food Administration’s[2] verification projects of the industry´s microbial monitoring. It is decided that a so-called ‘shoreline survey’ is unnecessary because all possible sources of sanitary contamination are described in the sewage plans for the cities in the area, the beach water quality monitoring and in the analyses of the Ministry of Environment and Food under the auspices of the Water Framework Directive.
[1] Include shellfish and invertebrates such as echinoderms, ascidians and sea snails.
[2] Fødevarestyrelsen.
