A farm survey on the presence of dioxins and dl-PCB in beef production systems in Switzerland

In 2006, new maximum levels for the concentration of dioxins (PCDD/F) and dioxin-like PCB (dl-PCB) in food entered into force in the European Union [Regulation (EC) No 199/2006]. The Swiss Confederation decided to adopt these values from the 1 January 2009 on (RS 817.021.23). A previous appraisal showed that beef from extensive production systems in Switzerland may exceed the new maximum level of 4.5 pg WHO97-TEQ·g-1 fat. In order to identify the reasons of the presence of dioxins (PCDD/F) and dioxin-like PCB in Swiss beef, a detailed survey was conducted on eight farms in 2008. Depending on the production system, on each farm several suckler cows and their calves or fattening bulls and heifers were selected and followed over several months. Samples of soil, milk, forages, concentrates and meat were taken and analyzed according to standard protocols. The sum of PCDD/F and dl-PCBs in soil averaged 1.4 pg WHO97-TEQ·g-1 dry matter (DM) across all farms. The mean value found in feed samples was 0.25 pg WHO97-TEQ·g-1 feed (88% DM), which is considerably lower than the legal maximum level of 1.25 pg WHO97-TEQ·g-1 feed. The mean value of milk from suckler cows was 2.75 pg, and the one of milk from dairy cows was 2 pg WHO97-TEQ·g-1 fat. Although two individual beef samples (out of 36) slightly exceeded the legal limit of 4.5 pg WHO97-TEQ·g-1 fat, the mean value of all beef samples was 2.3 pg WHO97-TEQ·g-1 fat. The results did not allow to establish direct relationships between the presence of contaminants in feeds and milk or beef and they showed that variation in PCDD/F and dl-PCB contamination of meat within the same farm was very high. It can be concluded that the situation in Switzerland seems not to be alarming and that no particular measures have to be taken. Nevertheless farmers should be aware that extensive production coupled with absence of delay between weaning and slaughtering may induce some risk for producing non compliant beef.