Dear Colleagues, I have attached a letter from Nathalie Delrue, Administrator in the Health and Safety Division at the OECD. They are requesting specific data related to in vitro genetic toxicology tests. I have also pasted the letter below. Please note that the deadline to send data is 5 April, and it should be sent to Tim Singer from Health Canada. Please feel free to let me know if you have any questions. Best wishes, Kristie Dear Colleagues, This letter is a follow up to the call for data that I sent you in December 2012 (Letter ENV/EHS/ND/ch/2012.14). At that time I requested that you send historical negative control data for the in vitro micronucleus test, (TG 487), the in vitro chromosomal aberration test (TG 473) and the in vitro gene mutation test (TG 476). I would like to thank all of you who responded to this call and sent data. The data collected on TG 473 and 487 have been used by a consultant for the Secretariat to perform a statistical analysis and support the determination of the optimal number of cells to be scored in these TGs. The work has not started yet on TG 476 and before it starts, the lead country group for the review of genotoxicity Test Guidelines recommended that data be gathered on a few cell lines in addition to those for which data were requested in December 2012. In particular, for CHO cells, the last call for data was made specifically for Hprt data in CHO-WBL cells, and thus excluded other CHO variants, such as CHO-K1 and AA8 cells, which have been used extensively for conducting Hprt mutation assays. In addition, TG 476 includes Hprt assays conducted with other cell lines, like TK6 cells and L5178Y cells, and possibly gpt assays conducted with AS52 cells. If you have any negative control or solvent control data for assays in these cell lines, we would appreciate your contributing it. Finally, if there are additional solvent/negative control data for Hprt assays conducted with V79 cells that were not sent in response to the first call for data, please take this opportunity to send it to us. Thus, I’d be very grateful if, in addition to the data you’ve already sent for TG 476, you could also provide data on other cell types, as described below under “Useful information”. As with the previous data that have been collected, the information will be used to determine the average spontaneous mutant frequency across multiple laboratories. Ideally individual data (per culture) will be needed when cultures are duplicated. Useful information: • Experimental conditions such as: - Cell line and cell variant, and source of the cells - Treatment duration - Expression time - With or without S9 • Individual negative control culture data: as mutations frequencies/ million cells This individual culture data should ideally be in an Excel spreadsheet from which it can be extracted for subsequent analyses and can be easy to match up with the conditions the study was carried out under such as with or without S9, treatment time and cell line. Some laboratories have quite a significant historical database that could take a considerable time to compile. If you are in this situation, feel free to limit yourselves to up to the most recent 20 experiments. Like was done for the previous call for data, Tim Singer will collect the data and remove identifying information for those who wish to provide data anonymously. Please send tabulated data to Tim Singer at Tim.Singer@xxxxxxxxxxx<mailto:Tim.Singer@xxxxxxxxxxx> by 5 April 2013. Your help is greatly appreciated. Kristie Sullivan Secretary, ASCCT www.ascctox.org<http://www.ascctox.org>
Attachment:
ND 2013-02_call for genotox data.pdf
Description: ND 2013-02_call for genotox data.pdf
