Last reviewed 3 November 2016

Gill Pagliuca looks at the potential effects of endocrine disruptors and how they are being regulated in the EU.

What is an endocrine disruptor?

An endocrine disruptor, or endocrine disrupting chemical (EDC), is defined by the World Health Organization (WHO) as “an exogenous substance or mixture that alters function(s) of the endocrine system and consequently causes adverse effects in an intact organism, or its progeny, or (sub)populations”. In more simple terms, it is a substance that may affect the hormones in the body with potentially adverse effects. Hormones are substances produced by the body that act in very small amounts and at precise moments in time to regulate the body. Endocrine disruptors interfere with these natural hormone systems, and may adversely affect both humans and wildlife. Effects may include:

  • impaired fertility, such as reduced sperm counts

  • effects on the development of offspring, such as birth defects and changes to neurological development such as reduced IQ and behavioural difficulties

  • effects on metabolism such as diabetes and obesity

  • the development of some types of cancer, particularly those associated with the sex organs including breast and ovarian cancer in women, and testicular and prostate cancer in men

  • in wildlife, effects such as egg thinning and feminisation of fish and other aquatic organisms.

These health effects can be felt long after the exposure has stopped. Pregnant women and developing children are believed to be particularly vulnerable to endocrine disruptors and exposure to them in the womb may have life-long effects and even consequences for the next generation.

Why are they a problem?

Endocrine disruptors include a wide range of chemicals that may be used across a wide range of sectors including:

  • flame retardants such as polybrominated diphenyl ethers (PBDEs)

  • plasticisers such as diethylhexyl phthalate (DEHP) and bisphenol A (BPA)

  • pesticides such as DDT and tributyltin

  • pharmaceuticals, such as hormonal contraceptives

  • naturally occurring substances, such as phytoestrogens.

Pesticide residues may be found in our food, while other substances are used in a wide range of products in our homes and workplaces including food packaging, cosmetics, toys, furniture, floor coverings, etc.

Recent studies have estimated that the cost to the EU economy of adverse effects from these chemicals could be more than €150 billion in health care costs and lost earning potential.

How are they being regulated?

The regulation of endocrine disruptors is a developing area. In 1999, the European Commission adopted a strategy on endocrine disruptors, and the development of legislation on chemicals since then has taken this strategy into consideration. As part of this strategy, a Priority List of potential endocrine disruptors was established, to be further assessed and prioritised for regulatory action.

A wide variety of regulations including legislation on plant protection products, biocidal products, chemicals (REACH) and cosmetics is being used to control exposure to these substances.

Consumer pressure may also lead to voluntary controls on substances, and local regulatory action, as has been the case recently with BPA which has been widely removed from items such as baby bottles.


Under REACH, endocrine disruptors are identified as substances of very high concern (SVHCs) using the criteria for substances considered to “give rise to an equivalent level of concern” (Article 57(f)).

SVHCs may be added to the Candidate List, triggering immediate requirements to inform customers where these are present at a level of over 0.1%. Of the 169 substances currently on the Candidate List, 21 have been identified as having endocrine disrupting properties as one of the criteria for their inclusion on the list. Many endocrine disruptors are also classified for other properties of concern, such as carcinogenicity or reproductive toxicity. Substances on the Candidate List may then be prioritised for addition to the Authorisation List, after which their use will be banned in Europe except in limited circumstances where an exemption is given or an authorisation is in place. One such chemical that has been regulated in this way is the plasticiser DEHP, which was banned from use in the EU from February last year.

The Authorisation List, while limiting use in the EU, does not, however, stop imported articles from containing these substances, so further controls may also be required to control exposure to these substances, in the form of restrictions in Annex XVII of REACH, or in other sectoral EU legislation such as toy safety, etc.

More chemicals are expected to be controlled in this way in the future as they are identified as endocrine disruptors. The European Chemicals Agency (ECHA) has initiated a screening programme to identify substances that should be subjected to further screening by regulators. This screening might result in further studies being carried out, including potentially requests to REACH registrants to carry out additional testing. If a substance is identified as an endocrine disruptor as a result of this screening, further regulatory action can be expected. Substances of potential concern can be identified through the various ECHA lists such as CoRAP and PACT-RMOA.

Tests and criteria

There are no simple tests or criteria that have been established, internationally or at EU level, for identifying substances with endocrine disrupting properties, and identification is currently made on a case-by-case basis on consideration of the evidence.

Efforts to develop more formal criteria are underway, and earlier this year, the Commission proposed two new sets of criteria to be used for endocrine disruptors: one under the biocidal products legislation, the other under the plant protection products legislation. These draft criteria have been subject to much criticism from both industry and environmental groups, though for different reasons.

On the one hand, industry has criticised the EU’s approach of setting hazard-based criteria, rather than taking a risk-based approach as preferred by industry, which they say may lead to the unnecessary removal of some substances from the market. Industry and some governments would prefer a risk-based approach that would allow the use of hazardous substances posing a low risk. On the other hand, environmental groups believe the EU approach has set the bar too high for identifying suspected endocrine disruptors and will not result in many harmful substances being removed.

With regard to testing, traditional toxicology tests are often not helpful in identifying these substances, as these tests are often not designed to identify effects at low exposure levels. Also, a wide range of effects on humans and wildlife must be screened for. The OECD has been doing a lot of work in developing guidance and adapting test methods to help identify endocrine disruptors; indeed it reports that it has spent nearly half of its resources on this over the last 20 years.


Endocrine disruptors are an area of increasing concern and regulatory action in the EU and beyond. These substances are being controlled in the EU through a number of different regulations including REACH, biocides and plant protection products regulations. Efforts to develop well-defined criteria and tests for these substances are ongoing.