dédié à l'identification des Perturbateurs Endocriniens
Key points of our tests
Tests validated or in validation process by OECD
Performed on whole endocrine systems exposed in vitro
Ethical alternative method to animal testing
Tailor-made protocols adapted to your needs
Explanation of our testing methodologie
We perform testing on different types of samples in order to respond to different questions :
• Detect potential endocrine activity
• Measure effects of these activities on living organisms
• Identify modes of action
At early stage hormonal mechanisms are similar to those of adults and they are well maintained through the evolution of species.
In order to conduct tests we use we use Medaka (fish from asian ricefields) eggs and Xenopus (amphibian) eggs, just after hatching. Samples are tested during 24 to 96 hours after induction with hatched eggs.
Fish fry induced by exposure to the estrogenic hormone (ethinyl estradiol). The fluorescence is induced in the liver.
Eggs harbor a genetic construct composed of the promoter of the naturally occurring target gene driving expression of a fluorescent gene (GFP).
The level of fluorescence is proportional to the effect.
Endocrine disruption is revealed by an increase or decrease in fluorescence.
Fluorescence reveals the natural reaction of the organisms
Interview with our team of experts on the endocrine system:
Why choose a whole organism performed in vitro?
"Only an assessment of endocrine activity on an entire organism can provide information on the entire signaling pathway. And thus minimize the risk of false positives or false negatives that could occur with a receptor based approach. However, the challenge was to create models which combine whole organism testing and compliance with ethical issues".
What are the main advantages of this technology?
«The hormonal mechanisms at this early stage are similar to those of adult stages. Moreover they are preserved through the species evolution including human beings. In order to quantify the hormonal activity, we use a reporter based on the expression of green fluorescent protein which reveals the endocrine effect. Our choice in using this technology is that we can measure the natural reactions of early life stage organisms without modifying their physiology or their genomic mechanisms».
Which endocrine axes should be tested (estrogenic, androgenic, thyroid)?
«Several endocrine axes could be potentially impacted by endocrine disruptors. But at this stage, European regulation is focused on three hormonal pathways for which criteria of disruption could be established: Estrogenic, Androgenic (with steroidogenesis) and Thyroid. Defining a testing strategy will then depend on the existing data. If you have none or a lack of information from existing data, we may recommend to investigate the 3 axes. However, based on indications suggesting an endocrine effect, you may want to explore a specific mechanism using a specific model or even defining a tailored-made protocol which would allow elucidating the mode of action. This could contribute to the conclusive additional data required by regulatory authorities.
It is important to keep in mind that there is a high degree of cross-talk between the different axes».
Can one test identify an endocrine disruptor?
«No, endocrine disruptor identification is hazard based and requires conclusive data to establish the plausible link between the mode of action and an adverse outcome. Neither endocrine activity nor an adverse outcome are sufficient to identify an endocrine disruptor. Our aim is to provide you with data contributing to a weight of evidence approach, which will allow you to make a decision and adapt your testing strategy».
What are the communication rules regarding Endocrine Disruption?
«Actually there are 2 points in order to correctly answer this question.
1st point is regulatory.
Product claims and consumer communication are very much regulated. Only "authorized" claims may appear on products / media related to the products. So in the absence of a regulatory framework for endocrine disruption labeling, it is recommended to avoid any mention on the products or any advertisement. For any question, you may contact the authorities to get their opinion.
2nd point is scientific.
It would be incorrect to say that a product is "without endocrine disruptors" because variation in endocrine signaling is inherent to living organisms. Our endocrine balance is constantly modified by our environment or by contact with foods or natural or chemical substances. It is therefore very difficult to guarantee the absence of endocrine risk. To eliminate the danger that an endocrine mechanism may lead to a harmful effect, it is necessary to have a large data set. Often several tests and a review of literature data are needed to properly evaluate a substance. The question is particularly complex as interactions between the substances in a product or a mixture can distort the endocrine evaluation. This is why, concerning communication, it is important to show pedagogy and caution».
Results at a glance
In order to facilitate understanding of the results and to adapt each report as much as possible to its end use, we can deliver results on several levels:
This depends on the planned use: regulatory focus, R&D, evaluation of your raw materials and finished products, portfolio screening, ...