Brussels, 20/03/2013 (Agence Europe) - Not all substances which are active on the endocrine system are necessarily endocrine disruptors. This depends on the existence of reasonable proof demonstrating that the substance can have a harmful effect resulting from its interaction or interference with the endocrine system, as there are no scientific criteria to date which establish a distinction between active substance and endocrine disruptors, according to the European Food Safety Authority (EFSA) in a scientific opinion on the assessment of the risks of endocrine disruptors, which was published on 20 March.
EFSA was tasked by the European Commission (DG SANCO) in September 2012 with answering two questions: how can an endocrine disruptor be defined? How can the undesirable effects be distinguished? This opinion was keenly anticipated in order to help the Commission - which is responsible for managing risks to protect consumers and the environment from any risks associated with endocrine disruptors which may be present in the food chain - to develop criteria for phyto-pharmaceutical products by the end of the year. It is also particularly important as it will form the basis for the EU's strategy for endocrine disruptors, which is being prepared by the European Commission and is expected this year. However, it does not come to any conclusions on the most important question. “There is no specific scientific criterion defined to distinguish between the potential harmful effects of endocrine disruptors and a normal regulation of bodily functions or adaptive responses”, state EFSA, adding that “experts must assess the weight of the available evidence on a case-by-case basis”.
In order to define endocrine disruptors, EFSA has adopted the definition of the World Health Organisation (WHO), which in February acknowledged that these chemical substances which are present everywhere in everyone's life constitute “a global threat” to human health and the environment.
The experts of the Scientific Committee on substances active on the endocrine system concluded that the internationally agreed tests currently available or soon to be available can identify the interference of certain chemical substances with four important endocrine pathways in mammals and fish known to be sensitive to endocrine disruption. “The Authority has reviewed the currently available testing methods to assist risk managers in defining what may or may not be an endocrine disruptor using science-based criteria. Our opinion also underlines the need for further testing strategies to be developed to test the substances in a systematic and transparent way”, said Hubert Deluyker, Director of Science Strategy and Coordination at EFSA. Professor Tony Hardy, the Chair of EFSA's Scientific Committee, added: “Current tests generally are adequate for mammals, fish and to a lesser extent also for birds and amphibians and cover four important endocrine pathways. However, no single test is sufficient to decide whether a substance is an endocrine disruptor and several tests need to be done and then assessed together by experts in a weight-of-evidence approach”.
EFSA takes the view that a risk assessment approach which takes account of both the potential harmful effects of substances active on the endocrine system and of the likelihood of exposure to these substances will make the best use of the available information to regulate their use.
The EFSA opinion also looks briefly at several questions related to tests on chemical substances which are not associated solely with the phenomenon of endocrine disruption, notably “windows of susceptibility” (critical periods of development, such as conception, pregnancy, infancy, childhood and puberty, during which the body may be more susceptible to chemical substances, thereby increasing the likelihood of the appearance of adverse effects in the short term or later in life), and other questions related to chemical toxicology and still a matter for scientific debate, such as low-dose effects, non-monotonic dose-response curves and exposures to multiple chemical substances. On these questions, EFSA recommends that additional work be carried out to clarify in a broader context how these various aspects could impact on current risk assessment approaches and testing strategies for any chemical substances. Whereas EFSA's work on this topic is concerned chiefly with endocrine active substances related to the food chain (such as pesticides), its contribution forms part of a wider initiative co-ordinated by the European Commission and intended to support an informed EU decision-makers' updating of current legislation in a variety of areas (chemicals, pesticides, biocides). The European Medicines Agency, the European Chemicals Agency, the European Environment Agency and the Joint Research Centre are therefore also involved in this process and contributed to the EFSA opinion.
Confusion added to the debate. The EFSA opinion was a big disappointment for PAN Europe, which accuses EFSA of adding confusion to the debate by bringing in a new category of substances: endocrine active substances, which could risk undermining the current rules on pesticides (Regulation 1107/2009, which makes no mention of this new category and aims simply to ban pesticides with endocrine disrupting properties which may cause adverse effects). PAN Europe criticises EFSA for failing to propose criteria either for endocrine disrupting properties or for adversity.
It may be recalled that, in a resolution adopted on 13 March, the Parliament called on the EU to take immediate steps to regulate endocrine disruptors by including them in the extremely concerning substances covered by the REACH regulation (see EUROPE 10806), and that it also expressed its “total disagreement with the attempts to introduce the activity criteria as the definition threshold for endocrine disruptors”. (AN/transl.fl)