Facts and Allegations
Wild Salmon obtain the natural pinkish-red color of their flesh from the carotenoid astaxanthin which is consumed in their prey - largely krill.
Farmed Salmon (aquacultured) are fed formulated diets that include synthetic carotenoids astaxanthin and canthaxanthin in order to duplicate the natural flesh color of wild salmon. Without them, the flesh of the farmed salmon would appear grayish and less appealing. Additionally, the pro-vitamin A and anti-oxidant nature of these synthetic carotenoids have been documented to help the growth rate and survivability of young salmonoids.
Synthetic astaxanthin is considered by the U.S. Food and Drug Administration (FDA) to be a color additive and therefor must be identified as such on the label of farmed salmon. The aquacuture industry considers this labeling unfair as the words "color added" or "artificial color" imply that a coloring agent has been used in processing which is not the case. The industry also argues inconsistencies exist between FDA and USDA labeling requirements as chickens are allowed under USDA rules to be fed carotenoids without any mention of color additives in their labeling.
Farmed
salmon is imported to the U.S. from numerous countries all around the
world. Each country sets and enforces its own standards on allowable
conditions including feed content.
In July of 2007, a ConsumerReports article expressed concern that while about 80% of seafood sold in the U.S. is imported, only about 2% of it is tested by the FDA. This places added concern on the safety of aquacultured imports as their feed source is beyond the direct control of the FDA with little chance of harmful product levels being detected.
ConsumerRerorts also reported that farm-raised salmon have higher levels of dioxins and PCBs (likely carcinogens in humans) than wild caught which is probably due to fish feed made from fish caught in polluted waters. These industrial chemicals are fat-soluble meaning they can be stored in the body's fat for years. C.R. recommends you purchase farmed salmon from the U.S., Canada or Chile as their levels of PCBs and dioxins tend to be lower.
Despite concerns of contaminates in farm-raised salmon, the FDA does not recommend avoiding it as detected levels have remained within allowable limits and therefore the benefits of the Omega-3 fatty acids outweigh the risks.
There are numerous organizations accusing the farmed-salmon industry of gross business practices that are dangerous to consumers and harmful to the environment. Some of these accusations include the mass use of antibiotics to combat parasites and disease that arise quickly within the cramped housing of salmon in ocean pens. Waste runoff and fish that escape are said to spread additional harm to surrounding areas. The aquaculture industry claims this is misinformation maliciously spread to discredit their business which competes with the wild salmon industry. Internet search engines regarding these matters can direct viewers to numerous sites that address perspectives from both sides.
Salmon,
whether wild caught or farm raised, has not been the subject of mercury
concerns as have other fish with Omega-3 benefits such as tuna and
swordfish.