Background: Benzene is an established leukemogen at high exposure levels. Although low-level benzene exposure is widespread and may induce oxidative damage, no mechanistic biomarkers are available to detect biological dysfunction at low doses.Objectives: Our goals were to determine in a large multicenter cross-sectional study whether low-level benzene is associated with increased blood mitochondrial DNA copy number (mtDNAcn, a biological oxidative response to mitochondrial DNA damage and dysfunction) and to explore potential links between mtDNAcn and leukemia-related epigenetic markers.Methods: We measured blood relative mtDNAcn by real-time polymerase chain reaction in 341 individuals selected from various occupational groups with low-level benzene exposures (> 100 times lower than the Occupational Safety and Health Administration/European Union standards) and 178 referents from three Italian cities (Genoa, Milan, Cagliari).Results: In each city, benzene-exposed participants showed higher mtDNAcn than referents: mtDNAcn was 0.90 relative units in Genoa bus drivers and 0.75 in referents (p = 0.019); 0.90 in Milan gas station attendants, 1.10 in police officers, and 0.75 in referents (p-trend = 0.008); 1.63 in Cagliari petrochemical plant workers, 1.25 in referents close to the plant, and 0.90 in referents farther from the plant (p-trend = 0.046). Using covariate-adjusted regression models, we estimated that an interquartile range increase in personal airborne benzene was associated with percent increases in mtDNAcn equal to 10.5% in Genoa (p = 0.014), 8.2% (p = 0.008) in Milan, 7.5% in Cagliari (p = 0.22), and 10.3% in all cities combined (p < 0.001). Using methylation data available for the Milan participants, we found that mtDNAcn was associated with LINE-1 hypomethylation (–2.41%; p = 0.007) and p15 hypermethylation (+15.95%, p = 0.008).Conclusions: Blood MtDNAcn was increased in persons exposed to low benzene levels, potentially reflecting mitochondrial DNA damage and dysfunction.

This study evaluates effects of good burning practice and correct installation and management of wood heaters on indoor air pollution in an Italian rural area. The same study attests the role of education in mitigating wood smoke pollution. In August 2007 and winters of 2007 and 2008, in a little mountain village of Liguria Apennines (Italy), indoor and outdoor benzene, toluene, ethylbenzene, and xylene (BTEX) concentrations were measured in nine wood-heated houses. During the first sampling, several mistakes in heating plant installations and management were found in all houses. Indoor BTEX concentrations increased during use of wood burning. Low toluene/benzene ratios were in agreement with wood smoke as main indoor and outdoor pollution source. Other BTEX sources were identified as the indoor use of solvents and paints and incense burning. Results obtained during 2007 were presented and discussed with homeowners. Following this preventive intervention, in the second winter sampling all indoor BTEX concentrations decreased, in spite of the colder outdoor air temperatures. Information provided to families has induced the adoption of effective good practices in stoves and fire management. These results highlight the importance of education, supported by reliable data on air pollution, as an effective method to reduce wood smoke exposures.Implications: Information about burning practices and correct installation and management of wood heaters, supported by reliable data on indoor and outdoor pollution, may help to identify and remove indoor pollution sources. This can be an effective strategy in mitigate wood smoke pollution.

Residential proximity to industrial sites has been associated with adverse effects on human health. Children are more susceptible to airborne environmental exposure because their immune and respiratory systems are still developing. This study aimed to investigate whether living close to an oil terminal in Genoa where there is higher VOCs exposure is associated with an increased rate of school absenteeism because of disease in primary school children. Five schools were chosen for the recruitment of children and students residing in the industrial site (A) were compared to those living in residential sites (B). Sixty-six of the 407 students involved in the project were also selected for VOC monitoring. Source apportionment was carried out by comparing profiles of VOCs; principal component analysis was performed to study the correlation between profiles, and Kriging interpolation model was used to extend profiles to all participants. The concentration means of total VOCs were significantly higher in the industrial areas compared to controls. Adjusting for potential confounders, children who lived in area A had a significantly higher risk of being absent from school due to sore throat, cough, and cold compared to controls. o-Xylene, which is dispersed during the industrial activity, showed clear evidence of a significant association with respiratory symptoms.

The impact of volatile organic compounds (VOCs) on indoor air quality and on human health is widely recognized. However, VOC contamination in hospital indoor air is rarely studied and chemical compounds that singularly do not show high toxicity are not submitted to any regulation. This study aimed to compare VOC contamination in two different anatomical pathology wards in the same hospital. Hydrocarbons, alcohols, and terpenes were sampled by passive diffusive samplers. Analytical tests were performed by thermal desorption coupled with gas chromatography and mass spectrometry detector. Results highlighted a different VOC pollution in the two wards, due to the structural difference of the buildings and different organizational systems. The scarcity of similar data in the literature shows that the presence of VOCs in pathology wards is an underestimated problem. We believe that, because of the adverse effects that VOCs may have on the human health, this topic is worth exploring further.