the same fatty tissues in fish that are such a good source of omega-3s are also potentially dangerous because they tend to have high levels of various types of pollutants.
Among these are dioxin, PCBs, and mercury.
PCBs, or polychlorinated biphenyls, are a type of synthetic chemical that was widely used from the 1930s to the 1970s in products such as paint, lubricant, inks, coolants, caulking compounds, and electrical equipment. These chemicals have dispersed throughout the environment and trace levels are found everywhere. PCBs do not break down easily and they are present throughout the food chain because
they are stored in the fatty tissues of animals, including fish. The negative health effects of PCBs can include:
- Thyroid problems,
- Weakened immune response,
- Neurological development problems in foetal and infant growth
PCBs accumulate in the body over a lifetime. This means that women who consume more than one or two portions of oily fish per week when they are young, will still be exposing their foetuses to the PCBs in this fish at any point in the future if they become pregnant. For this reason, the FSA recommends that women should not consume more than one or two servings of fish per week.
Mercury is another pollutant that accumulates in fish. People less than 16 years of age and pregnant women and their unborn children are among those at high risk for methyl-mercury poisoning, which damages the nervous system and kidneys. Women who intend to become pregnant should completely avoid marlin, swordfish, tuna, and shark beginning at least three months prior to conception if possible.As for the fish themselves:
They should continue to avoid these fish for the remainder of their pregnancy and while they are breastfeeding. Mercury can penetrate the brain-blood-barrier and is particularly toxic to the brain development of foetuses. This advice is based on the latest guidelines by the Committee on Toxicity of Chemicals in Food at the Food Standards Agency
52% of the world's commercial fish species are fully exploited.Not only fish suffer -
17% are over exploited.
8% are depleted.
Depending on the type of technology used to capture a target species, any number of nontarget species may be affected. Dolphins, whales, sharks, rays, various marine mammals, sea birds, and a large number of commercially useless fish are all accidentally killed and discarded into the sea.Quiz: How big is a modern fishing net?
Nets, trawls, and lines all contribute to the by-catch problem. Between 22% and 80% of fish by weight is discarded depending on the type of fishing operation.13 Every segment of the marine
ecosystem is damaged by these activities.
Gillnets are another highly destructive means of catching fish. Until recently, these long open nets were set out in lengths of up to 50kms - that's the equivalent of 500 football pitches laid end to end. These nets were and are frequently lost, left to drift through the oceans continually killing sea life in their path. As many are made from non-biodegradable materials, they can continue doing damage for years. They are now limited to 2 kilometres in length (which is still 20 football pitches)Ok, so let's eat farmed fish, right? well -
As is usually the case, unnatural crowding leads to disease problems. A primary concern to both the salmon industry and its critics is the flourishing of sea lice in salmon populations. Sea lice are small parasitic crustaceans that feed on the blood and tissue of salmon. In the wild, salmon rid themselves of sea lice by migrating into freshwater each year, but because farmed salmon are reared in the ocean for their entire life cycle, the sea lice flourish unchecked. The surrounding environment is affected because a reservoir of parasites in the farm, continually infects wild fish populations.And to top it, every Kilo of farmed fish contains 2 Kilo of wild fish. Sounds absurd?
To protect their product from sea lice, farmers use a variety of methods including:
It is worth noting that the above four chemical treatments of sea lice are said by some experts to be both carcinogenic and hormone disrupting
- Chemical bath with Azamethiphos, an organophosphate, which is ten times more toxic than the chemical Dichlorvos, which it is replacing because the sea-lice have developed some immunity to it.
- Chemical bath with Cypermethrin, a nerve-toxin, which is harmful to shellfish, and is viewed as a major public health risk when improperly used as sheep dip
- Oral treatments with Teflubenzuron, a carcinogenic insecticide that may persist in the environment, and inhibits the shell formation of invertebrates, including crustaceans in the water around salmon cages.
- Oral treatment with Emamectin, which is very harmful to shellfish and remains in the flesh of farmed fish.
Fishmeal is used, whether or not it contains by-catch, because most species of farmed fish are carnivorous and do not grow rapidly on a vegetarian diet of grain and soy feeds. But unless fish are fed a plantbased diet, there is no net increase in the amount of fish available to us from the seas; in fact there is a net loss. Given the feed conversion ratio above - for every kilo of fishmeal fed to farmed fish, we get back only half a kilo.But if we ban fish, what about the fishermen?
The fishing industry is happy to invoke the image of small town fishermen being driven to ruin by environmental regulation, but it is the advent of these destructive industrial operations that threatens the small-coastal fishermen and the stocks they depend on, not policies aimed at sustaining stocks. Local coastal fishing is less damaging, more efficient, produces better quality fish, and is not the primary environmental threat, but cannot compete in the current market.There's more horrors in the original, but there's also some hope, some reasonable policy proposals, as well as simple guidelines for personal action.
The list below is far from exhaustive, so we have given lots of other sources of information if you'd like to do more. But whatever you do, do something.
If you are choosing fish
- If you do not already eat fish, do not start. The health benefits of fish are scientifically valid, but there are plenty of ways to eat a healthy diet without fish.
- If you are concerned about the levels of omega-3 fatty acids in your diet, eat more walnuts (and walnut oil), and the oils from flaxseed/linseed and hemp. These more unusual sources are available at most health food stores and are widely accepted vegetarian source of omega-3s.
- If you eat beef and dairy products, make sure the animals were fed on grass and clover (all organic ones are) as this increases levels of omega-3s in the meat and milk.
Pregnant women should seek out the latest information on the potential harm to their babies' development from mercury, dioxin, PCBs and other pollutants that maybe found in high concentrations in certain fish. The Food Standards Agency's recommendation is to avoid all fish listed as having high mercury content. This includes marlin, shark, tuna, and swordfish.
- If you do eat fish, use your purchasing power to help the oceans by supporting the MSC-Label, which ensures your fish came from a sustainably managed source.
- If you choose to purchase farmed fish, make it organically farmed fish.
- If the place where you buy your fish does not have MSC or organic fish, ask them to stock it. Most outlets should be eager to please their customers! If the fish package or label does not give you enough - or any - information about the healthiness of the product, or if it was produced sustainably - ask the retailer or write to the manufacturer. You have a right to know.
- Make sure that the fish you are eating is recommended by a reputable guide, such as The Good Fish Guide from the Marine Conservation Society. Also see A guide to healthy and sustainable fish, below.
Eat one portion of oily fish per week, or its equivalent from vegetarian sources, to maintain levels of omega-3s.
Do not eat more than one or two servings of fish per week. And when you do eat it, really appreciate it - perhaps saving it for special occasions
Tell them that, as your elected representative, you are not happy with what they are doing to protect fish stocks for the future. Based on what you have read in this report, you might want to suggest one or more of the following policies:
- your MP. Find out who it is by calling the House of Commons Information Line on 020 72194272 or visiting www.locata.co.uk/commons. You can write to your MP at the House of Commons, London, SW1A 0AA
- your MEP. Check the map on this website to find out who it is http://www.europarl.org.uk/uk_meps/membersmain.htm
- the fisheries minister, Ben Bradshaw, at the Department of Environment, Food and Rural Affairs, Fisheries Directorate, Defra, 3-8 Whitehall Place, London SW1A 2HH www.defra.gov.uk/fish/fishindx.htm
- Reducing the size of the EU industrial fishing fleet and spending the EU subsidies instead on retraining and regeneration in the areas affected.
- Establishing a network of marine protected areas around the EU, especially around spawning grounds.
- Ending the exploitation of other countries' fishing grounds, and instead spending the money on investing in those countries' sustainable fishing and fish processing industries.
- Banning the most environmentally destructive types of fishing, such as bottom trawling.
- Enforcing the existing regulations - for example by using vessel tracking - so that those who violate the law have to face serious penalties.
- Encouraging, rather than discouraging, the production of other sources of omega-3s acids. For example, VAT is currently charged on hemp seed production in the UK as it is classed as a nonfood product.
- Changing official government advice to eat more fish, from any source. If everyone followed this advice fish stocks would be in an even worse state.
If we can save the fish - we can save the planet. I'm affraid that the "if" there might be "and only if".