According to the Food and Agriculture Organization of the United Nations (FAO), food security exists "when all people at all times have access to sufficient, safe, nutritious food to maintain a healthy and active life".
According to this, the Maximum Residue Limit of a pesticide is established as the highest legal limit of concentration of a pesticide residue allowed in food or feed, based on good agricultural practices and the lowest consumer exposure, needed to protect all vulnerable consumers.
The MRL should be set at the lowest possible level, consistent with good agricultural practices for each pesticide, to protect vulnerable groups such as children and unborn children.
In the context of the European Union, the (EC) No. 396/2005 regulation, unifies European residues legislation with the European Food Safety Authority (EFSA), in the assessment of the MRL that is safe for all European consumer groups.
At the international level, the MRLs are not harmonized, thus the need to establish Import Tolerances. This parameter bases the MRL on uses registered in foreign countries to allow the import of treated products and facilitate international trade. It should be noted that FAO and the World Health Organization (WHO) established the Codex Alimentarius Commission in which the Codex Committee on Pesticide Residues is responsible for establishing the Codex MRLs.
Along with pesticides, there is a range of alternative zero residue products, commonly called biopesticides. These manage to increase consumer safety since they are products with little or no environmental risk.