Aflatoxins are highly toxic substances naturally formed by the fungus Aspergillus flavus on foodstuffs, particularly nuts and dried fruit grown in warm humid conditions. They have been shown to be carcinogenic in animals, and aflatoxin B1, the most toxic, is classified as both a human carcinogen and mutagenic. Commission legislation meant that the nuts had to be tested in Europe as well as in America, therefore holding up the products in ports and slowing down the importing process and adding to the cost for importers because of extended waiting times. Only the UK and the Netherlands had made agreements with the US to rely soley on their testing. However, now the Commission has decided to allow aflatoxin testing to be carried out in the US, reflecting a high level of confidence in their food export safety system. Although American peanuts are the most expensive, this news could be a spur to the market, encouraging European manufacturers to use US peanuts to avoid having to endure extensive waiting times while the product be tested. Louise McKerchar, European marketing director of the American Peanut Council, said: "The pre-export certification approval by the European Commission is great news for European manufacturers looking to add value to their products with American peanuts." The approval by the Commission's Standing Committee on the Food Chain and Animal Health (toxicology section) states that: "The frequency of the physical checks on the consignments covered by the decision shall be significantly reduced." As well as simplifying and speeding up the process for importers and users of American peanuts across Europe, this allows food and snack manufacturers to rely on the swift entry of the nuts into European ports. US peanuts are the first commodity product to be granted pre-export approval under the EU's food and feed controls legislation, European Parliament and Council Regulation 882/2004. The approval follows an audit of the US system by the EU's Food and Vetinary Office last September, and replaces existing agreements that had been in place with port authority officials in the UK and the Netherlands since 1999 and 2000 respectively.