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No. 121: Sanitary survey report 7: Skive Fjord, Lovns and Risgårde Bredning

Larsen MM, Jakobsen HH, Göke C, Hendriksen NB, Rømer JK, Mohn C, Jensen AN & Schultz AC 2018. Sanitary survey rapport 7: Skive Fjord, Lovns og Risgårde Bredning. Aarhus Universitet, DCE – Nationalt Center for Miljø og Energi, 110 s. - Teknisk rapport fra DCE - Nationalt Center for Miljø og Energi nr. 121.
http://dce2.au.dk/pub/TR121.pdf

Summary

Regulation (EC) No 854/2004 of the European Parliament and the Council of 29 April 2004 lays down specific rules for the organisation of official controls on products of animal origin intended for human consumption. Classification of production areas for live bivalve molluscs 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 the previous classification on the basis of this is used. The Danish practice is described in ‘muslingebekendtgørelsen’, which is summarized in Appendix 11.

The report covers production areas P17, P18, P19, P20, P21, and P22 situated in Skive Fjord, Lovns and Risgårde Bredning (In short “Skive-Lovns-Risgårde”). The covered production areas within Skive-Lovns-Risgårde are marked ‘Rapportområde’ on the maps in this report.

The report recommends a microbiological sampling plan consisting of several designated sampling points and sampling frequencies for the individual production areas. It is further discussed whether merging of production areas into fewer areas could be an option in the future to reduce the number of sampling points, without compromising food safety.

The report is supported by publicly available data from monitoring of microbiological contamination in Limfjorden north and west of Mors where the concentrations of E. coli and Salmonella are determined in samples of mussels etc. taken at different sampling points within each area. The report points to the most precautionary fixed sampling points for future monitoring.

In summary, the sanitary survey of Skive-Lovns-Risgårde identified a generally, with few exceptions, microbiologically homogeneous and relatively clean area with only rare occurrences of resent relevant critical microbial contamination.

The data set represents the 10-year period 2008-2017 and revealed that 97 % of a total of 1,014 samples contained E. coli within the A-level (<230 E. coli/100 g); none of 350 tested samples were positive for Salmonella. However, the data cover only seven of the nine mentioned production areas, no data being available during the last three years from the P18 area.

Summary of recommended sampling programme

Based on an assessment of sources and transport routes for microbiological contamination (sanitary survey) verified against historical microbiological data on Skive-Lovns-Risgårde, a microbiological monitoring programme is recommended for each of the production areas in Skive-Lovns-Risgårde.

In each of the recommended monitoring programmes, proposals for a sampling location, classification status (preliminary or permanent) and a sampling plan are outlined.

Based on the results from the sanitary survey of the production areas, supported by the historical data sets on the number, frequency and E. coli concentration in samples, it is assessed that as a whole (bottom and aquaculture) the individual production areas P17, P19, P20 and P21 are considered suitable for permanent classification with a future sampling frequency of at least eight samples per year over a three-year period. P22 is suggested as preliminary classified, with a future sampling frequency of minimum 12 samples per year during the next three-year period.

In contrast, P18 does not reach the status of permanent classification, due to lack of data through the past three years (last data were achieved in 2009). If areas without permanent classification are to be upgraded to permanent classification, the EU guideline requires that the collection of data should include at least 12 samples for the latest six months or data from 24 samples over the last three years.

The report is divided into main chapters that provide a summary of identified microbiological contaminants. Appendices 2-9 serve as starting point of the main chapters. Appendix 10 is a detailed review of all historical microbiological data from mussel monitoring consisting of the fishery’s own-check and the Danish Veterinary and Food Administration’s[2] verification projects of the industry’s microbial monitoring. It was 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 live bivalve molluscs, echinoderms, tunicates and gastropods.

[2] Fødevarestyrelsen.