Codex standards are a series of food standards and guidelines complied by WHO and the Codex Alimentarius Commission of the Food Agriculture Organization, which are acknowledged and adopted by some western countries and also serve as important references for many countries when formulating national regulations. Codex Stan 72-1981(2007 version) is the existing codex standard for infant formula, adopted by EU and Hong Kong. It lays out strict requirements for various aspects of infant formula products, including the essential/optional ingredients and their contents, food additives, contaminants (pesticide residues), packaging, labelling, etc.