Criteria For Evaluating Ecotoxicity Data Ready For Use

« Backers say aim is to remove ‘bias’ towards GLP studies
A group of European scientists has published a set of criteria for reporting and evaluating ecotoxicity data (CRED), when deriving predicted no-effect concentrations (Pnecs) and environmental quality standards (EQSs).

“Our aim is that CRED will replace the Klimisch method in the European frameworks,” said one of its architects, Marlene Ågerstrand from Stockholm University’s department of environmental science and analytical chemistry.
Ecotoxicity studies need to be assessed for their reliability and relevance, before they can be used to derive Pnecs and EQSs. Klimisch evaluation criteria are generally used for this, but the system has attracted criticism, largely because it favours tests following OECD guidelines and Good Laboratory Practices (GLP). This can mean that the criteria seek out industry tests over those run by academics.

Last year, NGO Pan-Europe published an analysis of pesticide dossiers, suggesting that use of the Klimisch criteria had led industry to dismiss 500 “important” academic articles showing adverse effects of pesticides.
“The use of CRED would be a big improvement,” said Hans Muilerman, chemicals officer at PAN-Europe. “Klimisch keeps on being used on a massive scale in Brussels regulatory affairs to decide on reliability,” he added.

Describing the Klimisch criteria as « a tool that allows you to do the check in a minimum amount of time », he accused industry of using them to discount “unwanted academic studies”, while government experts turn to it because of time constraints.
CRED differs by providing more guidance and by giving equal weight to standard and non-standard data, said Dr Ågerstrand. The method builds on Klimisch to assess studies using a set of 20 reliability and 13 relevance criteria.

As with Klimisch, CRED has four reliability categories:

• reliable without restrictions;
• reliable with restrictions;
• not reliable; and
• not assignable

Experts assess studies based on test methods used, for example, on whether there are appropriate controls, whether exposure duration is defined, and whether statistical methods are appropriate. Relevance criteria include whether reported endpoints fit a substance’s mode of action.


The CRED team also makes reporting recommendations for new studies.

“An ecotoxicity study in which all important information is reported is more likely to be considered for regulatory use, and proper reporting may also help in the peer-review process,” write the authors in Environmental Toxicology and Chemistry.

The researchers hope that the criteria will help to make risk assessors’ decisions “more consistent”, as well as increase transparency. However, they also stress that the criteria should not be used as a box-checking exercise. Some flexibility may be required, as well as expert judgement, they say.

“Risk assessors should not reply on scoring systems to disregard evidence and studies; all information needs to be taken into account,” said Vito Buonsante of NGO ClientEarth. “If the CRED system does turn out to be more effective in taking into account the results of studies that are not GLP compliant or that do not follow OECD test guidelines, it will be more than welcome.”
He called for all guidance documents from EU agencies to eliminate any reference to the Klimisch scoring system to evaluate studies. »

Sources :
Article by Emma Davies
Journal abstract :
PAN-Europe report « Missed and dismissed » :
Cet article n’engage que son auteur/ This article is the sole responsibility of the author.