SciPi 145: Peer review of the genotoxicity, toxicokinetics, and carcinogenicity of a pesticide
Given the number of cancer studies available for 1,3-D, is there a need to rely upon cancer bioassay data for structurally similar chemicals?
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(4 Answers)
Answer Explanations 4
The differences in response to similar chemicals can only be approximated and should not be extrapolated if human exposure is expected. For instance, 1,3-D can be genotoxic but is mostly detoxified via GSH. However, there will always be a ratio of detoxification to toxic escape of reactive species. This ratio may change with chemical structure of the compound.
I think that there are enough 1,3-D 2 year carcinogenesis studies in rats and mice , and it is not necessary to rely upon cancer bioassay data for structurally similar chemicals.
sufficient data available for 1,3-D, structurally similar chemicals may not undergo identical biotransformation reactions and thus any conclusion may be highly uncertain
In my opinion, we have an adequate database to assess the potential carcinogenicity of 1,3-D.
Expert 11
04/18/2019 02:31Looks like agreement, I would not add the NTP studies to an evaluation due to presence of epichlorohydrin and potentially other contaminants ?
Expert 6
04/22/2019 17:33Yes, not add the NTP studies due to the presence of epichlorohydrin in Telone II used for that study.
Expert 2
04/24/2019 08:06There are contrary views throughout this survey as to the ability of a 1% epichlorohydrin impurity to explain away ALL the positive findings in the NTP bioassays.