Oxidative damage and genotoxic effect in mice caused by sub-chronic exposure to low-dose volatile organic compounds

Abstract

Volatile organic compounds (VOCs) are widely used as constituents of household chemicals. Although adverse health effects have been reported, long-term exposure to low-level VOCs mixture has not been studied. Especially, there is a lack of substantial information on the sensitive biomarkers and carcinogenic markers. In the present study, we examined oxidative stress and genotoxic effects of sub-chronic low-dose VOCs mixture (formaldehyde, benzene, toluene and xylene). Male Kunming mice were exposed to 0 (control) and three different doses of VOCs mixture (group 1S, 5S and 10S) for 90 d (2 h/d). Group 1S is 0.10, 0.11, 0.20 and 0.20 mg/m³, group 5S is 0.50, 0.55, 1.00 and 1.00 mg/m³, group 10S is 1.00, 1.10, 2.00 and 2.00 mg/m³, which, respectively, corresponded to 1, 5 and 10 times of indoor air quality standard (IAQS) in China. One day following VOCs exposure, oxidative stress markers in lung, 8-hydroxy-2'-deoxyguanosine in bronchoalveolar lavage fluid and genotoxicity (DNA damage) in liver were examined. Results showed that exposure to VOCs (IAQS dose) resulted in oxidative damages of lung, which were supported by the significant changes on reactive oxygen species, reduced glutathione (GSH), GSH S-transferase, total antioxidative capacity, malondialdehyde, protein carbonyl and nitric oxide (NO). Moreover, oxidative stress markers in group 5S and 10S (except NO) in lung were affected significantly. In addition, VOCs exposure also induced significantly DNA damage in liver. Our study suggested long-term VOCs inhalation at low levels caused oxidative stress and genotoxicity response in mice. Since effects were seen at the current IAQS level, further studies below this level are necessary.

Oxidative Stress and Genotoxicity of Long-Term Occupational Exposure to Low Levels of BTEX in Gas Station Workers

“…This result suggested that exposure to BTEX in air may increase the DNA damage in refueling workers, and the comet assay could be a useful detection method for occupational exposure to BTEX via inhalation. Besides, there are animal experiments suggesting that long-term VOC inhalation, including BTEX inhalation at low levels, can cause oxidative stress and a genotoxicity response in mice [34]. Results showed that exposure to BTEX (indoor air quality standard dose) results in oxidative lung damage, which is supported by significant changes in GSH and MDA.…”

Consumer exposures to laser printer-emitted engineered nanoparticles: A case study of life-cycle implications from nano-enabled products

“…The presence of such gaseous compounds can influence the biological response to inhaled aerosols (Wang et al, 2013b, Wang et al, 2013a, Ebersviller et al, 2012). In particular, exposure to VOCs is associated with adverse changes in the pulmonary and cardiovascular system, including inflammation and heart rate variability, as well as changes in gene expression (Song et al, 2013, Weichenthal et al, 2012).…”

Re-evaluation of the WHO (2010) formaldehyde indoor air quality guideline for cancer risk assessment

“…Also, we excluded animal studies with mixtures where effects of FA could not be disentangled (e.g. Wang et al 2013a) and studies with exposures to FA aerosols (e.g. Lima et al 2015) as the WHO IAQG is set for gaseous FA.…”