nearly 3 times the level of PCBs, more than 3 times the level of PDBEs, and nearly twice the level of dioxins and furans seen in the wild population. On the other hand, "Update of the monitoring of levels of dioxins and PCBs in food and feed", a 2012 study from the European Food Safety Authority, stated that farmed salmon and trout contained on average a many times lesser fraction of dioxins and PCBs than wild-caught salmon and trout." A 2004 study, reported in Science, analysed farmed and wild salmon for organochlorine contaminants. They found the contaminants were higher in farmed salmon. Within the farmed salmon, European (particularly Scottish) salmon had the highest levels, and Chilean salmon the lowest. The FDA and Health Canada have established a tolerance/limit for PCBs in commercial fish of 2000 ppb A follow up study confirmed this, and found levels of dioxins, chlorinated pesticides, PCBs and other contaminants up to ten times greater in farmed salmon than wild Pacific salmon. On a positive note, further research using the same fish samples used in the previous study, showed that farmed salmon contained levels of beneficial fatty acids that were two to three times higher than wild salmon. A follow-up benefit-risk analysis on salmon consumption balanced the cancer risks with the (n–3) fatty acid advantages of salmon consumption. For this reason, current methods for this type of analysis take into consideration the lipid content of the sample in question. PCBs specifically are lipophilic, so are found in higher concentrations in fattier fish in general, thus the higher level of PCB in the farmed fish is in relation to the higher content of beneficial n–3 and n–6 lipids they contain. They found that recommended levels of (n-3) fatty acid consumption can be achieved eating farmed salmon with acceptable carcinogenic risks, but recommended levels of (n-3) EPA+DHA intake cannot be achieved solely from farmed (or wild) salmon without unacceptable carcinogenic risks. The conclusions of this paper from 2005 were that "...consumers should not eat farmed fish from Scotland, Norway and eastern Canada more than three times a year; farmed fish from Maine, western Canada and Washington state no more than three to six times a year; and farmed fish from Chile no more than about six times a year. Wild chum salmon can be consumed safely as often as once a week, pink salmon, Sockeye and Coho about twice