What’s new, Webinars
Tracking chemical exposures in the office
In a recent webinar, Dr. Anna Young presented a new study which used silicone wristbands as a novel method to monitor exposures to chemicals in the office environment.
The presentation discussed the role of buildings and personal care products in exposures to endocrine disrupting chemical mixtures. The presentation also highlighted concerns about chemicals that are not yet identified or thoroughly studied.
Chemicals in the office
Hormone-disrupting chemicals mimic hormones in ways that can disrupt human health. These hormone disruptions can have negative impacts on fertility, pregnancy, and infant development. Some of these chemicals are also associated with thyroid disease, diabetes, obesity, and certain cancers. Hormone-disrupting chemicals can be found in building materials, furniture, flooring, consumer products, and personal care products.
Young’s study set out to evaluate the hormone-disrupting potential of the mixtures of chemicals that people are exposed to in the real world. To do this, 243 office workers in the study wore silicone wristbands during four work shifts. With the Stapleton Lab at Duke and other collaborators, chemical extracts from the wristbands were analyzed for the following:
- Ninety-nine known chemicals of concern, including flame retardants, plasticizers, and pesticides.
- About 1,000 potentially unknown chemical features.
- Total hormonal activities towards estrogen, androgen, and thyroid hormone receptors in human cell assays. To do this, they exposed human cells in the lab to the extracts of the chemical mixtures from the wristbands and measured the amount of interference with the cells’ hormone receptors. These assays:
- rapidly quantify an immediate “health” indicator of exposures.
- reflect impacts from all the chemicals, not just the known or measurable ones.
- capture any combined mixture effects.
"CHE Science Snippet" Webinar Preview
Testing chemical mixtures
Young stressed that testing and regulating chemicals individually was insufficient for safety, given our exposure to complex chemical mixtures. That is why this study looked at the mixture effects of the chemicals:
“Traditional targeted methods that test only one chemical at a time cannot keep up with the rate of new chemicals entering the market. We need to evaluate our exposures to chemicals as the complex mixtures they are in the real world, not just as individual chemicals.”
Analysis of the wristbands showed that the office workers were exposed to a range of chemicals:
- The study detected 94 of the 99 targeted chemicals.
- Each study participant was exposed to about 800 different chemical features.
- Every single wristband sample was hormonally bioactive. This shows that the chemical mixtures that these people were exposed to could mimic or block hormones.
- 99% of the samples blocked thyroid hormone at its receptor.
- 96% blocked testosterone at its androgen receptor.
- 58% mimicked estrogen at its receptor.
Female office workers had greater chemical exposures. Their exposures were significantly more estrogenic, more anti-androgenic, and more complex with higher numbers of chemical features. One possible explanation for this finding is that they were also reportedly heavier cosmetic users than the male participants.
The study’s statistical models found that several known and unknown chemicals were important individual drivers of the identified mixture effects. Six targeted chemicals were identified as major drivers of the mixture effects on hormonal activities: DiBP (a phthalate), TPHP (an organophosphate), PCB-11 (a polychlorinated biphenyl), DDE (a pesticide), DnBP (a phthalate), and TnBP (an organophosphate). Numerous other chemical features with unknown identities or unknown sources were also important drivers of the overall mixture effects.
These mixture effects have important implications for risk assessment and regulations. Young stressed that in order to protect the health of office workers, organizations should commit to only purchasing healthier building materials that eliminate entire chemical classes of concern.
Visit the webinar page to watch the full recording, download the Webinar Highlights fact sheet, and find out more about this important research.
This organizational blog was produced by CHE's Science Writer, Matt Lilley.