I do surgeries on rats using isofluorane as anesthetic. This is a gas that the rats breathe in, but because of poor ventilation, the person doing the surgery in our lab also occasionally smells the isofluorane (it has a very distinct smell). When I found out I was pregnant I wasn’t sure if I should still be using isofluorane, so I asked google. Google told me:
“Pregnancy Category CIsoflurane has been shown to have a possible anesthetic-related fetotoxic effect in mice when given in doses 6 times the human dose. There are no adequate and well-controlled studies in pregnant women. Isoflurane should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.”
“Pregnant mice exposed to light doses of isoflurane were found to have an increased frequency of cleft palate, skeletal variations and fetal growth retardation (Mazze et al., 1985). At doses similar to those used in humans, other investigators have not observed teratogenic effects among the offspring of pregnant rats or rabbits treated repeatedly with isoflurane (Kennedy et al., 1977; Mazze et al., 1986). There are no epidemiological studies reporting congenital anomalies in children born to women exposed to isoflurane during pregnancy. Therefore, its risk in human pregnancy remains undetermined.”
Still, from this information I found it very hard to make an informed decision. So I decided not to use isofluorane but instead use injectable anesthesia for my surgeries. The surgeries that I do are also performed under ketamine/xylazine anesthesia, so I think that should be fine.
However, this whole search for a risk assessment made me realize how hard it is do determine exactly how dangerous something is for you. This is especially important when you’re pregnant (or breastfeeding), but also just for your own health. A friend of mine who also uses isofluorane had her PI tell her when she was pregnant that it was okay for her to use this. I don’t know where the PI found this information, or that ze just really wanted this post-doc to continue her work.
If you ask me, it would be great if there was someone you could ask how dangerous the things are that you encounter on a daily basis in the lab; someone who could tell you what to change when you are pregnant. For radioactivity this is very well documented, but in the lab you encounter so many things for which it is hard to determine the risk using google and common sense. Does this information exist somewhere that I just don’t know about? If not, this should be a thing!