A class of poorly researched endocrine-disrupting chemicals poses a much greater risk to the environment and humans than previously thought, according to the results of an EU research project. Project leaders say the findings emphasise the need for more robust coverage of endocrine disruptors in the EU’s Reach chemical reform.

The Comprendo project investigated androgens and anti-androgens. These are endocrine-disrupting chemicals (EDCs) that mainly interfere with female hormone systems. Until now 90% of endocrine disruption research efforts have gone into oestrogens, a separate class of substances mainly affecting males.

The project forms part of the wider Credo programme on endocrine disrupters. Its results were presented at a conference in Germany last Friday.

Coordinator Jorg Oehlmann told Environment Daily scientists found worryingly high levels of the substances in the environment, in areas such as the Po and Elbe rivers. "Measurements in the environment exceed by several orders of magnitude the levels that are safe for our test animals", he said.

The project looked at around 20 substances including pharmaceuticals and agricultural pesticides. Among them were fenarimol and vinclozolin, two of a group of eight pesticides currently the focus of an EU regulatory dispute.

Comprendo found "remarkably high risk factors" associated with the EDCs studied, professor Oehlmann said. The substances interfered with sperm and egg formation in a large range of animal species at "extraordinarily low" concentrations.

No industrial chemicals were assessed, but professor Oehlmann said new tests developed under Comprendo could now be used to test those suspected of endocrine disruption. Statistics indicated likely environmental contamination by a "considerable number" of unidentified problematic substances. "There must be further compounds out there", he said.

Professor Oehlmann said the results should make regulators reflect on the treatment of EDCs under Reach. In their first reading ministers said they should be included in the authorisation procedure designed to encourage chemical substitution. But the commitment is hedged with qualifications. "There’s a debate on whether they should be included under authorisation. Based on our experiences, I think this is really a must", the scientist said.