One of the big debates about endocrine disrupting chemicals is: Is there a threshold (a ‘safe level’) below which they don’t disrupt the endocrine (hormone) system?

The European Commission set up an expert advisory group on Endocrine Disrupters in 2011; CHEM Trust are part of this group. At their 5th meeting in February 2013 the experts discussed key scientific uncertainties when trying to determine thresholds for EDCs

The EU Commission’s Joint Research Centre (JRC) has finally published a report of this meeting, “Thresholds for Endocrine Disrupters and related Uncertainties”, which looks at the threshold issue in depth. Some key points from the report:

  • Most of the experts in the group agreed that thresholds of adversity for EDCs may be very low or absent during early development
  • Several experts also highlighted that it may be very difficult to determine thresholds with the current available standard tests.
  • Thresholds determined in laboratory experiments are not equivalent to the true biological threshold, as a study with more sensitive endpoints may lead to a lower threshold. This calls into question the reliability of current risk assessment approaches
  • Additional relevant uncertainties discussed ranged from low dose effects, non-monotonic dose response curves to mixture effects and critical windows of exposure.

Chemical Watch covered the report, including comments from CHEM Trust director Gwynne Lyons: