Loch Hope

Scrap Book

Risky Business

Letter from Sandy Leventon, Editor, Trout and Salmon, Peterborough

Daily Telegraph - 10 January 2004

Sir - Eating farmed salmon is obviously a risky business, but what your report (News, Jan 9) fails to mention is the devastation caused by salmon farms to the wild salmon and sea-trout off the Scottish west coast.

Rivers that once had an abundance of wild salmon and sea-trout are now virtually fishless: parasitic sea lice, attracted by the farmed salmon, attach themselves to the juvenile wild fish and eat them alive. One Argyllshire river, which my family has fished for generations, is now no longer let because there are no fish.

In my ignorance, I welcomed the arrival of salmon farms, thinking they would take the pressure off wild fish stocks. I now realise their existence has done more to ruin fragile wild fish stocks than anything else.

Scottish farmed salmon 'is full of cancer toxins'

By Roger Highfield, Science Editor

Daily Telegraph - 09/01/2004

Farmed Atlantic salmon from Scotland contains the highest levels of cancer-causing chemicals in the world, a new survey has found.

It was so contaminated that, according to American guidelines, it should be eaten only once every four months. Otherwise, it will increase the risk of cancer by at least one case in 100,000, say scientists.

A salmon farm on Loch Linnhe, near Fort William

Levels of cancer-causing substances - including PCBs, dioxins, dieldrin and toxaphene - were significantly more concentrated in farmed salmon then in wild fish, said to the study, published today in Science magazine.

Scottish samples of farmed Atlantic salmon were up to 10 times more contaminated than the least contaminated wild salmon, from Kodiak, Alaska. The cause is thought to be contaminated high-fat fish feed.

Compared with North America and Chile, concentrations of cancer-causing substances in most European farmed salmon are so high that, again following guidelines of the US Environmental Protection Agency, only one meal - around 200g - should be eaten every other month.

"We think it's important for people who eat salmon to know that farmed salmon have higher levels of toxins than wild salmon from the open ocean," said Prof Ronald Hites of Indiana University, who led the study.

"My choice would be, if I were to seek out farm-raised Atlantic salmon, to select north or south American sources, based on these data," added co-author Prof Barbara Knuth of Cornell University.

To cut contamination, farms should use feeds with less fish and more plant-based material, she said.

But Dr Charles Santerre, of Purdue University, Indiana, said the benefits of salmon - a good source of protein, vitamin D and heart-friendly fats - outweighed the risks. "We should be eating more farmed salmon," he said.

The point was echoed by Scottish Quality Salmon, which represents around two thirds of Scottish salmon production. It said the advice of the scientists was deliberately misleading.

"In fact, consumers should be reassured by this research, despite its rather obvious attempt to stir anti-fish farming headlines," said its technical consultant, Dr John Webster.

"It actually says that individual contaminant concentrations in farmed and wild salmon do not exceed US Food & Drug Administration (FDA) action or tolerance levels. This is true. PCB and dioxin levels in Scottish salmon are significantly lower than the thresholds set by international watchdogs."

David Sandison, general manager of Shetland Salmon Farmers' Association, said: "PCBs in the diet - a result of industrial pollution between the 1920s and 1970s - have fallen by 75 per cent over the past 20 years."

Sir John Krebs, the chairman of the Food Standards Agency, said the study did not raise any new food safety concerns: "Our advice is that people should consume at least two portions of fish a week - one of which should be oily like salmon. There is good evidence that eating oily fish reduces the risk of death from recurrent heart attacks and that there is a similar effect in relation to first heart attacks.

"We advise that the known benefits of eating one portion of oily fish outweigh any possible risks."

In the new study, by far the largest and most comprehensive of its kind, a North American team analysed approximately 700 farmed and wild salmon.

Salmon samples were bought from wholesalers in the world's eight major farmed-salmon producing regions and from retailers in a number of major cities.

For comparison, the researchers collected samples of five wild Pacific salmon species from North America - it said this could be eaten as often as eight times a month.

The study concluded that the contamination was likely to be related to salmon feed, a concentrated and high-fat mixture of other fish ground into fishmeal and fish oil.

It found higher contaminant concentrations in salmon feed from Europe than feed from North and South America, a result roughly consistent with the higher contaminant levels found in European farmed salmon.

To make it easier for consumers to follow the consumption advice identified in the study, the authors recommend that all farmed and wild salmon be clearly labelled and that the country of origin also be displayed, a suggestion backed by Scottish Quality Salmon. "We have been calling for that for quite some time," it said.

Since contaminants build up in fatty tissue, consumers may be able to reduce contaminants in farmed salmon by removing as much skin and visible fat as possible.