Keeping safe during pregnancy

Chemicals, radiation and noise are all hazards to anyone working in a chemistry lab, but even more so if pregnant. Surprisingly, little information is available regarding the specific workplace risks for pregnant chemists and their unborn children. This is partially due to limited research on toxicity or other hazards, and partially due to hesitancy from employers or institutions around liabilities. Institutions defer to medical professionals, but medical professionals don’t have expertise in chemical safety. In the end chemists are left to deal with both the assessment and mitigation of workplace risks to their pregnancy on their own. Those who are unable or not ready to disclose their pregnancy are even further isolated by the lack of available resources.

In 2020 Mary Kate Lane, a PhD student in the chemical and environmental engineering department at Yale University, US, and Malhet Garedew, at the time a postdoc in the same department, were both pregnant and bouncing between health and safety personnel and their doctors looking for answers. Then they were approached by their lab heads Julie Zimmerman and Paul Anastas, who asked them to lead a team of students working to address these exact questions. The result is a 25-page review, published open access in Chemical Research in Toxicology. ‘I was extremely excited,’ says Garedew of being asked to help write the review, ‘because what I was saying to myself was I wish somebody had a paper that had everything in one place. At least then I could make some kind of decision.’

Risks and hazards

The review contains all the available information on risks for pregnant chemists from a wide range of chemical hazards, including solvents, heavy metals, radiation, engineered nanomaterials and endocrine disruptors, as well as other aspects of the lab environment such as potential stress from heat, noise or psychological factors. For each risk they describe what is known about the vulnerabilities to pregnancy by trimester, an important detail because risks are often higher early on in pregnancy. They also provide, when possible, safer alternatives for some toxic chemicals. For both, the ethos of green chemistry was a big motivator behind the project.

According to Lane they started by looking for already-available resources, ‘and then when we weren’t really finding anything that had everything we wanted that’s when we were like, “OK, what are the things that chemists specifically work with every single day in the lab they need to be aware of?”’ Unfortunately they found insufficient information for many of these daily hazards. Existing reviews would group compounds like heavy metals or solvents together and make only general safety recommendations. Or for materials that vary in shape and size, studies could show very different results. ‘They can say gold nanorods of this size did not show any toxicity effects in this animal study, but then if you change the morphology, or change the size slightly, you can change the toxicity and then it can show toxic effects in this other animal study,’ says Lane. Often there just isn’t much toxicity research and most of it is done by injecting animals, leading to further ambiguity when the route of exposure in the lab is usually via inhalation or skin contact.

The group went to great lengths to get all the information they could to enable pregnant chemists to make the best decision possible. For example, when it came to x-rays, they turned to medical literature. ‘There isn’t really anything out there specifically about x-rays in pregnancy, but there are some papers on x-ray techs who work in healthcare, and their exposure,’ says Lane. ‘Then you can draw on that body of literature and make a more informed decision based on what you’re working with.’

Kathleen Flint Ehm, assistant dean for graduate and postdoctoral initiatives at Stony Brook University, US, and co-author of the 2011 National Postdoc Association’s A Postdoc’s Guide to Pregnancy and Maternity Leave, was relieved when she saw someone had finally put together this type of review. For her, this is not just a safety tool but an advocacy one too. ‘It’s always easier to have a difficult conversation around accommodations in the lab and time off and maternity leave if you can point to a review article like this that can summarise many of the issues for you.’

Jennifer Leigh, the vice-chair for research with the Women in Supramolecular Chemistry network sees this review as a first step to help raise awareness and now, ‘it’s about making sure that the people who need it have access to it’. She also thinks professional societies could have a larger role in these types of initiatives. ‘Ideally, it would be something that the professional bodies like the Royal Society of Chemistry, the American Chemical Society would do, keep up to date and provide.’