Jam-packed with omega-3 on the one hand and laced with toxic mercury on the other, fish and seafood are embroiled in an ongoing Dr Jekyll and Mr Hyde battle. At the end of 2010, public awareness campaign organisation Got Mercury? published its latest in a series of reports investigating the mercury content of fish and seafood sold in the US.
This most recent study was based on 98 fish samples purchased from (primarily sushi) restaurants and retailers across the state of California. All samples were found to contain detectable levels of mercury, and the 32 swordfish samples registered an average level of mercury almost 50% above US federal guidelines.
It is a rather disconcerting fact that mercury is present in virtually all fish and seafood to varying levels. The heavy metal enters the marine environment (as well as freshwater lakes) in natural ways, such as through rock weathering and volcanic activity, but also as a result of human activity, ie pollution, which, unfortunately, is not only the primary source of mercury contamination in fish but also a rapidly growing one. Emissions produced by coal-fired power plants and waste incinerators are two major culprits. The mercury emitted eventually ends up in the oceans and lakes where bacteria convert it to methylmercury (its organic form), which is readily absorbed by living organisms, including fish and seafood.
The mercury builds up over time, and hence concentrations are highest in older predatory fish. This is a growing concern for human health – methylmercury enters the bloodstream, penetrates the brain and is toxic to the nervous system. Its effects are particularly dangerous for the developing brains of foetuses and children.
Awareness is rising
Compared to salmonella in eggs and e coli in beef, which often cause instant outbreaks of food poisoning, excess consumption of mercury-contaminated fish tends not to trigger easily identifiable symptoms. This is one of the reasons why consumer awareness of the issue has not yet filtered into mainstream consciousness. This may be about to change, however. Media reports about the danger of consuming fish and seafood high in mercury are becoming ever more frequent, including those involving high-profile celebrities, such as Oscar-winning actress Hilary Swank.
Campaigns run by non-profit organisations are also driving this trend, and they are ubiquitous, including the previously mentioned Got Mercury? (actually a project of the Turtle Island Restoration Network) and Oceana, a body that aims to protect the world’s oceans.
Organisations such as these are pushing for US supermarkets to display mercury warning signs by their fresh fish counters, chiller shelves etc to bring the FDA’s official advice to shoppers’ attention. Some retailers, like Kroger, Safeway and, of course, Whole Foods Market, are already posting such notifications, but the industry as a whole remains reluctant to publicise its disturbing secret any more than absolutely necessary.
Low mercury – USP of the future
Some fish and seafood companies, however, have identified the mercury conundrum as a business opportunity, and are doing their best to inform consumers while at the same time providing them with fish and seafood low in mercury. Californian-based fish and seafood supplier Safe Harbor Foods, for example, tests all its large fish and fish known to contain higher levels of mercury individually and, provided it does not exceed the maximum level for the species of fish set out in the company’s published testing standards, the fish is awarded the Safe Harbor seal. Safe Harbor Certified Seafood is available in retailers and restaurants in California, Hawaii, North Carolina and Nevada.
Wild Planet Foods Inc, another Californian-based company, sells packaged fish products under its Wild Planet Foods brand. The range includes several varieties of low-in-mercury tinned wild albacore tuna. According to company data, Wild Planet Albacore Tuna contains only around 40% as much mercury as a rival national brand, and clocks in at 17% of the FDA maximum permitted level. As already mentioned, albacore tuna tends to be at the higher end of the mercury contamination spectrum, and so Wild Planet Foods’ products do seem to plug a gap in the market.
One more example is the New Hampshire company EcoFish Inc, which offers a range of frozen, pouched and tinned fish and seafood products under the EcoFish and Henry & Lisa’s Natural Seafood brands. They carry the Seafood Safe seal, which assures consumers that the products have been screened for environmental contaminants, including mercury and PCBs. Products include Henry & Lisa’s Natural Shrimp, Grab ‘n Go Wild Salmon and Wild Alaskan Salmon Burgers.
The demise of tuna?
Fish and seafood marketed as low in mercury may still be niche at the moment, but the mercury contamination problem is not going to go away. On the contrary, with coal-fired power stations and other sources of pollution increasing, fuelled in large part by the rapid economic growth of China and other emerging economies, the mercury load entering the world’s marine and fresh water environments is set to increase exponentially for the foreseeable future.
Although the previous examples were drawn from the US, no country (or fish species) is wholly unaffected by this, paving the way for a global trend in fish and seafood positioned as low in mercury. As the problem worsens and consumer awareness increases, testing and certification will play an ever more important role, as will the proliferation of fish species known to be least affected by mercury contamination, such as anchovies, catfish, Atlantic haddock, herring, salmon, sardines and tilapia.
The rising popularity of low-mercury fish species will inevitably come at the expense of others, in particular tuna, which has been enormously popular for so many years. Not all types of tuna are high in mercury, but none are particularly low, and the levels can only go up.
Because this is ultimately true for all fish and seafood, industry organisations and trade bodies would do well to concentrate their efforts on combating the root of the problem, and lobby far more strenuously than they do now to regulate the activities of polluters, ie by forcing them to install filtration systems to stop the mercury from entering the global waterways in the first place.