Academic journal article Environmental Health Perspectives

Barrier Capacity of Human Placenta for Nanosized Materials

Academic journal article Environmental Health Perspectives

Barrier Capacity of Human Placenta for Nanosized Materials

Article excerpt

BACKGROUND: Humans have been exposed to fine and ultrafine particles throughout their history. Since the Industrial Revolution, sources, doses, and types of nanoparticles have changed dramatically. In the last decade, the rapidly developing field of nanotechnology has led to an increase of engineered nanoparticles with novel physical and chemical properties. Regardless of whether this exposure is unintended or not, a careful assessment of possible adverse effects is needed. A large number of projects have been carried out to assess the consequences of combustion-derived or engineered nanoparticle exposure on human health. In recent years there has been a growing concern about the possible health influence of exposure to air pollutants during pregnancy, hence an implicit concern about potential risk for nanoparticle exposure in utero. Previous work has not addressed the question of whether nanoparticles may cross the placenta.

OBJECTIVE: In this study we investigated whether particles can cross the placental barrier and affect the fetus.

METHODS: We used the ex vivo human placental perfusion model to investigate whether nanoparticles can cross this barrier and whether this process is size dependent. Fluorescently labeled polystyrene beads with diameters of 50, 80, 240, and 500 nm were chosen as model particles.

RESULTS: We showed that fluorescent polystyrene particles with diameter up to 240 nm were taken up by the placenta and were able to cross the placental barrier without affecting the viability of the placental explant.

CONCLUSIONS: The findings suggest that nanomaterials have the potential for transplacental transfer and underscore the need for further nanotoxicologic studies on this important organ system.

KEY WORDS: barrier tissue, ex vivo perfusion, human placenta, nanoparticles, nanotoxicity. Environ Health Perspect 118:432-436 (2010). doi:10.1289/ehp.0901200 available via http://dx.doi.org/ [Online 12 November 2009]

**********

Humans have always been exposed to airborne particles through natural sources such as volcanoes, forest fires, or desert dust. After the Industrial Revolution in the 19th century, emission of anthropogenic particles into the atmosphere significantly increased. This increased exposure to respirable fine particles (< 2.5 [micro]m in diameter) and ultrafine particles (UFPs; < 0.1 [micro]m in diameter). Epidemiologic and in vivo studies have shown potential toxic effects of fine particles and UFPs on human health (Kreyling et al. 2004; Oberdorster and Utell 2002). When inhaled, UFPs are deposited in the respiratory tract and may provoke inflammation or granuloma formation in the lung and induce systemic effects such as pro-thrombotic responses (Nemmar et al. 2008) or cardiovascular changes (Alfaro-Moreno et al. 2007; Kreyling et al. 2004; Nemmar et al. 2007, 2008). Despite the presence of several highly efficient lung clearance mechanisms, different studies have shown that the transfer of nanoparticles from the lung to the blood is possible (Geiser et al. 2005; Nemmar et al. 2005; Rothen-Rutishauser et al. 2006).

With the broad use of nanotechnology, intentional production of nanoobjects in the size range of 1-100 nm has further increased the number and variety of nanoparticles to which humans can be exposed. New applications of engineered nanoparticles in nanomedicine such as nanoparticulate contrast agents (Rudin and Weissleder 2003), cancer treatments (Thiesen and Jordan 2008), and vaccines (Reddy et al. 2007) are in development that will be directly injected in the bloodstream of patients.

Most of the recent research dealing with potential health hazards of nanoparticles has focused on cells and tissues that are likely to come into immediate contact with airborne particles. There is a growing concern about the possible influence on health of the exposure to nanoparticles during pregnancy or early childhood (Lacasana et al. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.