People can come into contact with endocrine disrupting chemicals in various ways. Exposure can take place via oral ingestion, skin absorption, or inhalation. Exposure to endocrine disrupting chemicals is by no means always harmful. The harmfulness depends on the duration and frequency of exposure, and on how much of the substance you were exposed to.

The potential health effects can also depend on the stage of life during which you are exposed to these substances. For example, the effects of exposure during pregnancy, the period around birth or during a person’s youth or adolescence can be different from the effects of exposure in adulthood. This is because hormones play an important part in body processes in each of these life phases.

Definition and classification criteria

The World Health Organization (WHO) has formulated a definition for identifying and assessing endocrine disrupting chemicals. According to this definition, an endocrine disrupting chemical is a chemical that can affect the hormonal system of humans or other animals, potentially leading to harmful health effects. 
To classify a particular substance as an endocrine disruptor, there must be scientific evidence that it disrupts the endocrine system and that this disruption has adverse health effects, for example in the form of developmental disorders, reduced fertility or increased risk of certain illnesses. The classification of chemicals as endocrine disrupting chemicals is performed by Classification, Labelling and Packaging (CLP) or United Nations Globally Harmonized System of Classification and Labelling of Chemicals (UN GHS).

The official criteria of the CLP reads as follows:

  • The substance must have an effect on the endocrine system.
  • The substance must have an adverse effect in an intact organism, its progeny or subpopulations.
  • There must be a causal link between the endocrine effect and the adverse outcome.

Many studies are currently examining the potential health effects of endocrine disrupting chemicals. There is also extensive research underway to develop methods for measuring the effects of these chemicals and to apply the CLP criteria.

For more information about the role of RIVM in this context and specific research projects in which it is involved, see The role of RIVM and Projects.

Health effects

Endocrine disrupting chemicals can have harmful effects on our health. Scientific studies point to a link between various adverse health effects and these type of chemicals. Examples are:

  • infertility
  • congenital disorders
  • obesity
  • cardiovascular diseases
  • diabetes
  • metabolic diseases
  • some types of cancer

There is evidence that endocrine disrupting chemicals may contribute to the development of these health effects. However, many factors play a role in the onset of disease. These include hereditary factors, lifestyle and nutrition. Many diseases result from a combination of various factors. This makes it difficult to determine whether endocrine disrupting chemicals actually have harmful health effects.

Pregnancy and child development

Unborn babies, infants and children undergo rapid growth and development. This makes them particularly vulnerable to endocrine disrupting chemicals. Legislations aim to prevent persons from being excessively exposed to such substances, especially for sensitive periods such as pregnancy and the child’s development after birth. If a substance is known to be an endocrine disruptor, its use is restricted or banned altogether. For example, the European Commission has banned the use of bisphenol A in baby bottles.

For more information about endocrine disrupting chemicals and pregnancy, see the leaflet entitled Pregnant!