Irish dioxin levels at safe limits

Dioxin levels in the Irish environment are well within European Union limits, according to the latest Environmental Protection Agency (EPA) assessment.

The study, which was based on dioxin levels measured in cows’ milk in a 2008 survey, found all dioxin levels recorded “compared favourably” with those taken from a random selection of similar surveys conducted in other EU countries.

While consumer exposure to dioxins through the consumption of milk was not the object of the study, it found the highest levels of dioxins were below the legal limits.

The report found there was no evidence to link data obtained in its survey to the pork feed contamination incident at a Carlow pigfeed plant last year.

The incident, which caused one of the State’s worst food scares, was caused when fuel oil containing polychlorinated byphenyls (PCBs) was used convert out-of-date food for cattle and pig ration.

“There is no evidence in our results to suggest that there was burning of PCBs going on prior to the event,” EPA programme manager Dr Ciaran O’Donnell said.

Dioxins are a group of chlorinated organic compounds released into the atmosphere mainly from fires and other forms of combustion.

The vast majority are not considered environmentally significant at the levels normally encountered.

However, a small number of dioxins can be highly toxic and pose a risk to human health, causing a range of ailments from skin diseases to cancer and damage to the reproductive and immune systems.

Since the chemical processing industry in Ireland is relatively small, the most common sources of dioxins here are from traffic emissions, backyard burning of household waste [which is now illegal], and coal-fired power plants.

Dioxins leave a deposit on vegetation such as grass which is ingested by cows, which can be traced in their milk.

The EPA’s survey was carried out in June and early July last year, during the peak outdoor grazing season, by taking a series of milk samples from representative regional dairies.

Two samples from the south west of the country were found to have higher dioxin concentrations than elsewhere in Ireland, but they were still within the EU limit.

The study also tested, for the first time, for the presence of micro pollutants, such brominated flame retardants and brominated dioxins, which can arise from the incineration of certain wastes, but found no evidence of significant concentrations.

Dr O’Donnell said: “The concentrations of dioxins were low by international standards and comparisons”.

“The survey confirms the continuing low levels of dioxins and dioxin-like substances in the Irish environment,” he said.