06-14 baby in womb line art

[Image above] Credit: Adobe Stock

The promise of nanotechnology has started to materialize in many industrial sectors, as discussed in the April 2024 issue of Ceramic & Glass Manufacturing. But as nanomaterials become mainstream, it is crucial for scientists to understand the potential human health and environmental effects of nanoparticle exposure.

Titanium dioxide, a widely used additive, has received a ton of media attention in recent years due to the European Union’s ban on its use in food. The ban was driven largely by concerns related to the material’s nanoform, for which the possibility of genotoxicity could not be ruled out due to lack of data.

In addition, researchers at Stanford University recently showed that synthetic mesoporous silica, another widely used nanoscale additive in food and cosmetic products, may be more chemically reactive than previously imagined. But again, until more information is gathered on the nanomaterial’s possible toxicity mechanisms and effects, it is difficult to develop nuanced safety regulations for the substance rather than just blanket bans.

This month, Empa, the Swiss Federal Laboratories for Materials Science and Technology, issued a press release about a recent open-access study led by its researchers. The study aimed to shed more light on the developmental toxicity mechanisms of titania and silica nanoparticles during pregnancy.

As explained in the paper, there is ample evidence that nanoparticles can affect the healthy growth of a fetus, but the mechanisms involved are largely unknown. Most studies focus on the direct effects of translocated particles on fetal tissues. But several groups, as overviewed here, have investigated how nanoparticles could cause indirect harm by accumulating in the placenta and interfering with essential tissue functions and the release of signaling factors.

In the new study, the Empa researchers looked more closely at how the food-relevant nanoparticles, as well as diesel exhaust nanoparticles, affect the human placental secretome, i.e., the set of steroid- and proteo-hormones, metabolic proteins, growth factors, and cytokines that the placenta secretes to adapt maternal physiology to pregnancy.

However, to obtain meaningful results on the transport and effect of nanoparticles, the use of human placental tissue was a must because “The structure, metabolism and interaction of maternal and fetal tissue are unique and species-specific,” says Tina Bürki-Thurnherr, deputy head of Empa’s Laboratory for Particles–Biology Interactions, in the press release.

To acquire this tissue, they sourced fully functional human placentas from planned caesarean sections at the Cantonal Hospital of St. Gallen, Switzerland.

Testing on these samples revealed that nanoparticles disrupt the production of many messenger substances, with impaired blood vessel formation being the main result. On the other hand, development of the nervous system did not appear to be affected, though future analyses are needed to identify what other disorders the nanoparticles may trigger indirectly.

“As the effects can have an impact on the health of the pregnant woman and the development of her child, these findings should be taken into account in the risk assessment of nanomaterials,” Bürki-Thurnherr says.

The open-access paper, published in Advanced Science, is “Nanoparticles dysregulate the human placental secretome with consequences on angiogenesis and vascularization” (DOI: 10.1002/advs.202401060).