Current understanding of the toxicological risk posed to the fetus following maternal exposure to nanoparticles

ABSTRACT

Introduction: With the broad use of nanotechnology, the number and variety of nanoparticles that humans can be exposed to has further increased. Consequently, there is growing concern about the potential effect of maternal exposure to various nanoparticles during pregnancy on a fetus. However, the nature of this risk is not fully known.

Areas covered: In this review, materno-fetal transfer of nanoparticles through the placenta is described. Both prenatal and postnatal adverse effects, such as fetal resorption, malformation and injury to various organs in mice exposed to nanoparticles are reviewed. The potential mechanisms of toxicity are also discussed.

Expert opinion: The toxicology and safe application of recently developed nanoparticles has attracted much attention in the past few years. Although many studies have demonstrated the toxicology of nanoparticles in various species, only a small number of studies have examined the effect on a fetus after maternal exposure to nanoparticles. This is particularly important, because the developing fetus is especially vulnerable to the toxic effects of nanoparticles during fetal development due to the unique physical stage of the fetus. Nanoparticles may directly or indirectly impair fetal development and growth after maternal exposure to nanoparticles.

KEYWORDS:

• Nanoparticles
• fetus
• transplacental transfer
• toxicity
• mechanism

Article highlights

• NPs may accumulate in placental tissue or pass through the placental barrier after maternal exposure during pregnancy.

• The determinants of materno-fetal NP transfer include NP characteristics and the anatomical and functional state of the placenta.

• NPs can affect the developing fetus directly via particle translocation through the placenta or indirectly by inducing placental dysfunction or by activating inflammation or oxidative stress in exposed mothers.

• Fetal development can be adversely affected by maternal exposure to NPs both short-term in the maternal uterus or have a lasting impact after birth.

• A very limited number of fetotoxicological mechanistic studies of maternal NP exposure are available. The factors that likely play a role in NP-induced fetotoxicity include ROS, inflammatory reactions and DNA damage.

This box summarizes key points contained in the article.

Acknowledgments

Carol J of American Journal Experts revised the paper for phrasing, diction, and language conventions.

Declaration of interest

The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Additional information

Funding

This review was supported by the National Natural Science Foundation of China (51672122) and Natural Science Foundation of Guangdong Province (2015A030313299, 2016A030313673).