Personal Exposure to Ultrafine Particles and Oxidative DNA Damage

Abstract

Exposure to ultrafine particles (UFPs) from vehicle exhaust has been related to risk of cardiovascular and pulmonary disease and cancer, even though exposure assessment is difficult. We studied personal exposure in terms of number concentrations of UFPs in the breathing zone, using portable instruments in six 18-hr periods in 15 healthy nonsmoking subjects. Exposure contrasts of outdoor pollution were achieved by bicycling in traffic for 5 days and in the laboratory for 1 day. Oxidative DNA damage was assessed as strand breaks and oxidized purines in mononuclear cells isolated from venous blood the morning after exposure measurement. Cumulated outdoor and cumulated indoor exposures to UFPs each were independent significant predictors of the level of purine oxidation in DNA but not of strand breaks. Ambient air concentrations of particulate matter with an aero-dynamic diameter of ≤10 μm (PM10), nitrous oxide, nitrogen dioxide, carbon monoxide, and/or number concentration of UFPs at urban background or busy street monitoring stations was not a significant predictor of DNA damage, although personal UFP exposure was correlated with urban background concentrations of CO and NO2, particularly during bicycling in traffic. The results indicate that biologic effects of UFPs occur at modest exposure, such as that occurring in traffic, which supports the relationship of UFPs and the adverse health effects of air pollution.

Determinants of ultrafine particle exposures in transportation environments: findings of an 8-month survey conducted in Montréal, Canada

“…However, a high correlation between wind speed and mixing height meant that we could not estimate the independent effects of these two variables. Regardless, our findings are consistent with those of Vinzents et al (2005) who also observed a significant inverse relationship between temperature and wind speed and UFP exposures while bicycling in traffic. However, we were unable to identify other studies exploring the effects of ambient temperature and wind speed on UFP exposures in transportation environments.…”

“…Therefore, the exposure levels reported in this investigation must be interpreted with caution as they are likely conservative estimates of actual exposures in transportation environments. Nevertheless, the majority of particles produced by gasoline and diesel vehicles are between 0.02 and 0.1 mm in diameter (Morawska and Zhang, 2002), and previous studies employing P-TRAKs have observed significant associations between UFP counts and oxidative DNA damage (Vinzents et al, 2005) as well as changes in heart rate variability (Chan et al, 2004) and vasoconstriction (Rundell et al, 2007). Therefore, while the P-TRAK is not the most sensitive instrument available, it remains a valuable instrument in environmental epidemiology owing to its portability and relatively low cost.…”

“…Indeed, the impact of UFP exposures may be most troubling for individuals suffering from asthma or obstructive pulmonary diseases as pulmonary deposition is greatest for these individuals (Brown et al, 2002;Chalupa et al, 2004;Frampton et al, 2004). However, UFP exposures are also a concern for healthy subjects as recent findings suggest that traffic-related UFP exposures may lead to oxidative DNA damage (Vinzents et al, 2005). Therefore, there is currently a need to characterize UFP exposures in transportation environments because people spend a considerable portion of their day in these locations and evidence to date suggests that such exposures may have an adverse effect on respiratory and cardiovascular health.…”

Indoor ultrafine particle exposures and home heating systems: A cross-sectional survey of Canadian homes during the winter months

“…Nevertheless, variations in peak expiratory flow rates were more strongly associated with ambient UFP concentrations in one of these studies relative to larger particles (Pekkanen et al, 1997). Recently, UFP exposures were shown to contribute to oxidative DNA damage in healthy adults, with indoor exposures contributing most to cumulative exposure levels owing to the large amount of time people spend indoors (Vinzents et al, 2005). Therefore, future populationbased studies interested in the respiratory effects of UFPs may need to include indoor measures of UFP exposure to capture an accurate depiction of cumulative exposure profiles.…”

Exposure of Children to Ultrafine Particles in Primary Schools in Portugal

“…Ultrafine particles may originate outdoors, from vehicle emissions and gas-to-particle conversions (Levy et al, 2003;Vigotti et al, 2007). However, indoor UFP originate from a wide range of indoor sources and occupant-related activities such as cooking, smoking, cleaning, and painting (Wallace et al, 2002;Vinzents et al, 2005;Weichenthal et al, 2007). One of the potential approaches to control indoor air pollutant concentrations is to reduce emission sources (Oliveira Fernandes et al, 2008).…”