The Ministry of Health on May 17 banned the marketing of eels from Lake Garda, because they were contaminated with dioxin. The provision states that the ban will last one year and the Regions and Provinces concerned are invited to inform consumers about health risks.
The decision was made following analyzes of 102 samples of various fish (eel, whitefish, whitefish, pike, perch and tench) taken in 10 locations. The laboratories have identified the presence of a quantity of dioxins, furans and PCBs higher than the legal levels only in lake eels. This species was penalized because dioxins accumulate in animal fat and eels have a high lipid content.
The second clarification to be made concerns the values of dioxin, PCB and similar diosisne found which are 15-20% higher than those foreseen by the European Union (14 picograms / g is the average value found while 12 pyrograms / g is the value maximum of the norm) and in these cases the prohibition of marketing is automatically triggered. To reassure the population, the ministry ensures that the waters of Lake Garda are absolutely safe for bathing, and there is no problem with the quality of drinking water.
According to some experts in the field, the ministry’s provision comes late and should be more precise. The presence of dioxins in lakes is nothing new. The Swiss health authorities of the Canton of Ticino, which incorporate the upper part of Lake Maggiore in their territory, already in January 2008 emphasized the problem of dioxins in fish (see attachment).
In January 2009, the same Swiss authorities decided to ban the marketing of eels and agonis (a fatty fish also called alosa, or lake sardine) precisely because of the excess of dioxin.
In Italy no measures have been taken because the analyzes are not carried out and therefore the problem is non-existent. In the autumn of 2010, however, the laboratories were activated and it was discovered that the dioxin problem is common to many lakes including Lake Garda. Based on these indications, the ministry has decided to ban the sale of eels as expected.
The provision is correct but risks creating a certain alarmism, because the word dioxin is always scary, and the reaction of the citizens will probably be that of not eating lake fish for a year. It would be necessary to add some explanation to the decision, and make an adequate risk analysis based on the actual exposure of citizens.
For example, the Swiss authorities made distinctions when they banned the retail sale of some fish due to dioxin in Lake Maggiore. Prohibition of eating agoni from Lake Maggiore to minors under 18 and pregnant women, but they also told adults who fish as a hobby to limit consumption to 120 g per week, to make it clear that if taken in a reasoned way, the consumption of fish is not creates problems.
This recommendation suggests that the dioxin risk exists, but it should not be considered an alarm, but must be seen in an area where limited consumption is also allowed.
In Finland where similar problems are encountered for herring, health authorities advise young and pregnant women to eat only fish less than 17 cm long (juveniles) with a frequency of 1-2 times a month, because they have a of compatible dioxins. A similar argument is made for pike which, having a high mercury level, are not recommended for pregnant women.
Also in the United States, in some lakes, sport fishermen are distributed a brochure which recommends cooking fatty fish on the grill to limit the ingestion of dioxins, and to remove the fatty parts where the substance is found. Of course we are talking about an occasional consumption, but this message reassures the fishermen and gives the right dimension to the problem.
Perhaps also in Italy it would be useful to add some clarifications to the ban decided by the ministry, to avoid alarmism and the risk of abandonment by citizens of the consumption of all the fish in the lake (not just eels) as happens when the word dioxin appears. .
Document drawn up by the Swiss health authorities to explain what dioxin is, what is the danger and how to reduce ingestion (see attachment)
Consumers can limit their intake of dioxins and PCBs through a moderate, balanced diet (in particular, by reducing the amount of animal fat) and rich in fruit and vegetables.
The population can also actively contribute to the reduction of dioxin emissions into the environment by disposing of waste according to the regulations and by refraining from illegally burning waste at home (fireplaces and stoves) or outdoors. PCB emissions can also be reduced on construction sites or during disposal thanks to proper handling of PCB-containing materials (e.g. joint sealing compounds, paints, anti-corrosive coatings, electrical equipment and systems, residues from shredding processes ).
What are dioxins and PCBs?
In current usage, the term “dioxins” designates two very similar classes of substances, polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), often also referred to as PCDD / F. In recent times , due to their similar toxic action, some exponents (congeners) of the class of polychlorinated biphenyls (PCBs) have also been added. Substances belonging to this group are called “dioxin-like polychlorinated biphenyls” or “coplanar polychlorinated biphenyls” (Co-PCBs).
Unlike plant protection products, which are used in a targeted manner, ubiquitous environmental contaminants are so widespread that it is impossible to eliminate residues present in the environment and in foodstuffs in the short term. For this reason, every effort must be made to reduce background contamination.