When a chemical is found in a food product that is already on the market, a risk assessment can calculate whether it could pose a health hazard. A risk assessment can also determine before admission of a substance whether that substance is allowed to be in food products or may be used in food production – and if so, in which amounts. During an admission process for chemicals in food, threshold limits are derived for that substance. A risk assessment goes through various steps to determine whether there is a risk of health effects due to exposure to a chemical substance.

First, all the available information about the chemical is compiled to see if health effects could potentially occur. At this stage, a closer look is also taken to determine the concentration at which zero effects can be expected. We call this the ‘human health threshold value’ or reference value. Sometimes the reference value is already known, such as for substances which have had to go through an admission procedure, usually at a European level. In other cases, it still needs to be determined; this is often the case for substances which do not have an ‘owner’, for instance natural toxins or environmental contaminants.

Next, exposure to the relevant chemical is calculated as accurately as possible and compared with the human health threshold value to see whether there is a risk of potential health effects. These assessments also take into account the more vulnerable groups in society, such as pregnant women, the elderly, children and infants. Sometimes parts of the required information are not available, or not fully; in other cases, the results of the risk assessment are very inconclusive. In such situations, more refined methodologies and calculation models need to be applied to assess possible risks. 

Depending on the result of the risk assessment, governments can decide whether certain chemicals are allowed to be used in food production processes. Most chemical substances are assessed at a European level by the European Commission in consultation with the Member States. Other chemicals can be permitted in small quantities, but measures need to be taken if exposure exceeds certain levels. This could for instance mean that a food product needs to be recalled. In other cases, an agreement can be reached on the maximum amount (product standards) of a chemical substance or residues of that chemical that are allowed to be present in a food product.