An American non-profit organisation, The Council for Education and Research on Toxics, is suing leading coffee retailers in California over its claims that their products should carry cancer warnings. The lawsuit, which has been brought against about 90 leading companies including Starbucks, centres on the presence of a chemical called acrylamide, a known carcinogen that is a by-product of the roasting process. Coffee industry representatives argue that while acrylamide is present, it is at such low levels that it is harmless. The Council for Education and Research on Toxics argues that the industry is in violation of a California state law that requires goods to carry warning signs about the presence of hazardous chemicals. The lawyer fighting the case for The Council for Education and Research on Toxics, Raphael Metzger, says the aim of the suit – which has been running since 2010 – is to push the industry to remove the chemical from its products altogether. In 2008 a similar suit succeeded in forcing potato chip makers to remove the chemical from their products.