Comet Test in Saliva Leukocytes of Pre-School Children Exposed to Air Pollution in North Italy: The Respira Study.

Claudia Zani,Ilaria Zerbini,Umberto Gelatti,Gaia Claudia Viviana Viola,Donatella Feretti,Elisabetta Ceretti,Francesco Donato

doi:10.3390/ijerph17093276

Claudia Zani, Ilaria Zerbini + Show 5 more

Open Access

https://doi.org/10.3390/ijerph17093276

Copy DOI

Abstract

Air pollution is a well-known problem for human health, especially for children living in highly polluted urban areas. This study aimed to assess the relationship between airborne pollutants concentration and biomarkers of DNA damage in the buccal mucosa cells of pre-school children. DNA damage was investigated with comet test in saliva leukocytes taken from sputum of 3- to 6-year-old children living in Brescia, Northern Italy, collected during two consecutive winter seasons (2012–2013). The daily levels of PM10, PM2.5, NO2, CO, SO2, benzene and O3 in urban air were collected for the whole period. A questionnaire filled in by the children’s parents was used to evaluate indoor and outdoor exposure. DNA damage in saliva leukocytes was evaluated in 152 children and the means of tail intensity and visual score as DNA damage were 6.2 ± 4.3 and 182.1 ± 30.9, respectively. No demographic and indoor or outdoor exposure variable was associated with the two measures of DNA damage. No significant association between air pollution and DNA damage in children’s buccal leukocytes was found. In this study, the comet assay does not appear to be a valuable biomarker to detect DNA damage in children exposed to high levels of air pollutants, such as PM10, PM2.5 and NO2.

Highlights

Air pollution is a global problem: airborne or deposited pollutants can be found worldwide, from highly polluted to remote areas
DNA damage was investigated in saliva leukocytes taken from sputum: the children rinsed their mouths twice with mineral water and the mouthwashes were collected in tubes containing 25 mL of saline solution (NaCl 0.9%) in order to obtain leukocytes for the comet assay [42]
A total of 222 children were enrolled, for 152 of which biological samples were adequate for the comet assay

Summary

Introduction

Air pollution is a global problem: airborne or deposited pollutants can be found worldwide, from highly polluted to remote areas. Epidemiological studies have found a consistent association between exposure to airborne PM and the incidence and mortality for cardiovascular disease and lung cancer [8,9,10,11] and recently with diabetes and other chronic diseases, possibly through oxidative stress and inflammation [12,13]. Short-term mutagenicity assays can be used to detect DNA damage resulting from exposure to mutagens. Their use is increasing for biomonitoring people, since they allow the detection of early effects of chronic exposure to toxic agents [14,15], they are valuable for exposure to low doses and mixtures of toxicants, and they require a lower number of subjects and evaluation of objective parameters compared to traditional epidemiological studies [16]

Objectives

Methods

Results

Conclusion