Once in the bloodstream, fullerenes can spread in the entire body and pass on to the offspring during pregnancy or by lactation.
Surface modified fullerenes were not evaluated in the following.
In order to investigate the distribution of the particles in the body via the bloodstream, radioactively labelled, unmodified fullerenes were injected into rats. The fullerenes administered were detected in the liver, lungs, placenta and fetus. Fullerenes were also passed on to the offspring via breast milk. [1-3].
However, the dose of 0.3 mg 14C labelled fullerenes per kg body weight administered in the experiment is high and would not occur in reality. Nevertheless, this experimental approach confirms that not all biological barriers are an obstacle to such tiny nanoparticles as fullerenes (0.7 nm). Similar results have also been found in human placentas [4].
Literature 
- Sumner, SC et al. (2010), J Appl Toxicol, 30(4): 354-360.
- Synder RW et al. (2015), J Appl Toxicol, 35:1438-1451
- Sumner SCJ et al. (2015), J Appl Toxicol, 35:1452-1464
- Wick, P et al. (2010), Environ Health Perspect, 118(3): 432-436.