Organic foods and feeds for organically-reared avoid the use of all synthetic ingredients. Although the organic feed used in land farming had already replaced synthetic antioxidants with natural alternatives, it was more of a challenge in fish farming. The aquaculture industry has relied on synthetic antioxidants to stop the spoilage by oxidation of unsaturated fish oils, such as omega-3 fatty acids DHA and EPA, in order to maintain the nutritional value of oily fish. However, natural alternatives are now available. All those involved in the production of Soil Association-certified organic fish feeds and their ingredients have successfully switched to natural products in the first such requirement placed on any sector of the fish farming industry. Peter Bridson, Soil Association Aquaculture programme manager, said: "By using fishmeal and oil made from the recycled filleting wastes of fish already caught for human consumption, we already have the most sustainable feeds in the industry, and it is great to know that we can also protest their unique omega-3 fatty acids with natural antioxidants." The UK environmental charity established the availability of potential natural products and set a deadline of 1 July 2007 for only natural antioxidants to be used in the fish feeds and their ingredients. By working with fishmeal and oil manufacturers, feed mills and various companies developing natural antioxidant products, the necessary testing and development has taken place and the target has been met. Natural oxidants generally use extracts of plants, seeds and nuts, and have active ingredients including various forms of vitamin E tocopherols, vitamin C, gallates and diterpenes. The majority of non-organic fish feeds and their ingredients still contain synthetic antioxidants such as Butylated hydroxytoluene and Ethoxyquine. Exposure to Ethoxyquine in the workplace has been linked to allergic contact dermatitis because of its low acute toxicity. Sales of organic food grew by 30 per cent in the UK in 2005. Consumers have been drawn by health benefits from the lack of unnecessary chemical pesticides and artificial feed used. Organic is also better for the environment and provides more natural conditions for the animals.