Workshop Report 30

What are reproductive toxicity guideline studies? Why are they conducted? What can they achieve? Where are the gaps?

Jessica LaRocca
Dow AgroSciences, USA
graphThe presentation outlined the Product Safety Assessment process from hazard identification through dose-response, exposure assessment and finally risk characterisation. She described the regulatory drivers for toxicity testing and the guidelines for developmental and reproductive toxicity studies for industrial and agricultural chemicals. In this talk, epigenetics was defined as “heritable modifications superimposed on DNA base sequence that regulate 
gene expression.”
Dr LaRocca discussed the Anway et al papers on Epigenetic Transgenerational Actions of Endocrine Disruptors and Male Fertility and the usefulness of Vinclozolin as a possible model compound to help understand epigenetics (Anway et al, 2005; 2008). Different groups have tried unsuccessfully to reproduce this study’s findings (Schneider et al, 2008).
Several questions remain unanswered regarding epigenetics:
What are the dose-response relationships for these epigenetic effects as compared to apical endpoints?
Is identification of causal biomarkers necessary to demonstrate which epigenetic changes would be predictive of apical effects?
How do we identify which changes are adaptive and which are adverse?