Effects of lung exposure to carbon nanotubes on female fertility and pregnancy. A study in mice

Abstract

We studied the effects of preconceptional exposure to multiwalled carbon nanotubes (MWCNTs): mature, female C57BL/6J mice were intratracheally instilled with 67μg NM-400 MWCNT, and the following day co-housed with mature males, in breeding pairs. Time to delivery of the first litter, litter parameters, maternal inflammation and histopathology of lung and liver were recorded. In male offspring, locomotor activity, startle response, and daily sperm production (DSP) were assessed. In the dams, lung and liver bore evidence of MWCNT exposure when assessed 6 weeks and 4 months after exposure. A short delay in the delivery of the first litter was observed in exposed females. Litter parameters, behavior and DSP were similar in control and exposed groups. In conclusion, instillation of a single dose of MWCNT induced long lasting pathological changes in dam lung and liver. Theoretically, lung inflammation due to particle exposure could interfere with female reproductive parameters. Whether the observed lag in delivery of a first litter was in fact caused by exposure to MWCNT should be addressed in a study designed specifically to elucidate effects on the early processes involved in establishment of pregnancy. Exposure was not associated with changes in the assessed gestational or offspring parameters.

Keywords: ANCOVA; ANOVA; ASR; AVG; BAL; C-reactive protein; CNT; COX; CRP; DLS; DSP; Developmental toxicity; ENP; EPA; EU; Environmental Protection Agency (USA); GD; HE; ICP-OES; IL; Lung and liver pathology; MWCNT; Multiwalled carbon nanotubes; NIOSH; Nanotoxicology; National Institute of Occupational Safety and Health (USA); PND; PPI; Pregnancy; R(a); R(i); ROS; Reproductive toxicity; SAP; SD; SEM; SWCNT; TEM; TGA; TNF; X-ray diffraction; XRD; acoustic startle reaction; analysis of covariance; analysis of variance; average of tube movements for 100ms following onset of startle stimulus; bronchoalveolar lavage; carbon nanotube; cyclooxygenase; dB(A); daily sperm production; decibel, A-weighted; dynamic laser scattering; endotoxin units; engineered nanoparticles; gestation day; hematoxylin and eosin; inductively coupled plasma-optical emission spectrometry; interleukin; multiwalled carbon nanotube; optical absorption index; optical refractive index; postnatal day; prepulse inhibition; reactive oxygen species; serum amyloid protein; single walled carbon nanotube; standard deviation; standard error of the mean; thermogravimetric analysis; transmission electron microscopy; tumor necrosis factor.