DNA Damage in Buccal Mucosa Cells of Pre-School Children Exposed to High Levels of Urban Air Pollutants

Abstract

Air pollution has been recognized as a human carcinogen. Children living in urban areas are a high-risk group, because genetic damage occurring early in life is considered able to increase the risk of carcinogenesis in adulthood. This study aimed to investigate micronuclei (MN) frequency, as a biomarker of DNA damage, in exfoliated buccal cells of pre-school children living in a town with high levels of air pollution. A sample of healthy 3-6-year-old children living in Brescia, Northern Italy, was investigated. A sample of the children's buccal mucosa cells was collected during the winter months in 2012 and 2013. DNA damage was investigated using the MN test. Children's exposure to urban air pollution was evaluated by means of a questionnaire filled in by their parents that included items on various possible sources of indoor and outdoor pollution, and the concentration of fine particulate matter (PM10, PM2.5) and NO2 in the 1–3 weeks preceding biological sample collection. 181 children (mean age±SD: 4.3±0.9 years) were investigated. The mean±SD MN frequency was 0.29±0.13%. A weak, though statistically significant, association of MN with concentration of air pollutants (PM10, PM2.5 and NO2) was found, whereas no association was apparent between MN frequency and the indoor and outdoor exposure variables investigated via the questionnaire. This study showed a high MN frequency in children living in a town with heavy air pollution in winter, higher than usually found among children living in areas with low or medium-high levels of air pollution.

Micronuclei and other nuclear anomalies in buccal epithelial cells of children with chronic kidney disease

“…When frequencies of nuclear anomalies of condensed chromatin and karyorrhectic and pyknotic cells were compared in different healthy children populations, large variabilities were observed. While some of them (40,50), including our study, had much higher values, others (51) had lower values than the levels obtained in the study by Thomas et al (52). The causes of this variability may, in part, reflect genetic and non-specific exposure differences, or in part, technical factors and differences in the sample preparation and interpretation of the scoring criteria between laboratories.…”

Air pollution biological effects in children living in Lecce (Italy) by Buccal micronucleus cytome assay (the MAPEC_LIFE study)

“…For this purpose, a suspension of scraped BM cells from each sample was prepared [25]. The test tubes containing the cellular suspension were kept at −20°C and sent on ice to the University of Perugia which saw to their staining, fixing on slides and microscopic analysis.…”

“…In recent years, studies of MN frequency in the BM cells of children and young adults have shown cytogenetic damage in participants living in areas with high concentrations of particulate matter (PM) or oxidant pollutants [20][21][22][23][24][25]. Recently, Ceretti et al [25] found a higher frequency of MN in the exfoliated buccal cells (EBCs) of pre-school children living in a highly polluted town in the Po Valley in Italy than was observed in a pooled general population of the same age.…”

Air Pollution Exposure

“…Th ough not specifi c for air pollution exposure, biomarkers with the potential for future clinical application include exhaled nitric oxide, micronuclei frequency in buccal mucosa cells, microRNA in induced sputum samples, malondialdehyde in exhaled breath condensate, and serum IL-6 levels. 37,[55][56][57][58] Of the ILDs, IPF, in particular, is age-related, raising the possibility that lifetime cumulative environmental exposures may relate to the advanced cellular senescence seen in this disease. 23,59 Comprehensively characterizing the environmental contributors to fi brogenesis (either directly or through gene and environment interactions) may be an essential step in understanding the complex pathobiology of IPF.…”