Seasonal variations of DNA adducts in mothers and newborns exposed to polycyclic aromatic hydrocarbons in Mexico City

Polycyclic aromatic hydrocarbons (PAHs) are a component of air pollutants that are costly to measure using traditional air-quality monitoring methods. We used an epiphytic bio-indicator (moss genus: Orthotrichum) to cost-effectively evaluate atmospheric deposition of PAHs in Portland, Oregon in May 2013. However, it is unclear if measurements derived from these bioindicators are good proxies for human exposure. To address this question, we simultaneously, measured PAH-DNA adducts in blood samples of non-smokers residing close to the sites of moss measurements. We accounted for individual determinants of PAH uptake that are not related to environmental air quality through questionnaires, e.g., wood fires, consumption of barbecued and fried meats. Correlation and linear regression (to control for confounders from the lifestyle factors) evaluated the associations. We did not observe evidence of an association between PAH levels in moss and PAH-DNA adducts in blood of nearby residents, but higher level of adduct were evident in those who used wood fire in their houses in the last 48 hours. It remains to be determined whether bio-indicators in moss can be used for human health risk assessment.

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Sources and transformations of particle-bound polycyclic aromatic hydrocarbons in Mexico City

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-5-12741-2005 ◽

2005 ◽

Vol 5 (6) ◽

pp. 12741-12773 ◽

Cited By ~ 9

Author(s):

L. C. Marr ◽

K. Dzepina ◽

J. L. Jimenez ◽

F. Reisen ◽

H. L. Bethel ◽

...

Keyword(s):

Mass Spectrometry ◽

Polycyclic Aromatic Hydrocarbons ◽

Mexico City ◽

Aromatic Hydrocarbons ◽

Heterogeneous Reactions ◽

Field Campaign ◽

Aerosol Mass ◽

Aerosol Mass Spectrometry ◽

Polycyclic Aromatic ◽

First Time

Abstract. Understanding sources, concentrations, and transformation of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere is important because of their potent mutagenicity and carcinogenicity. The measurement of particle-bound PAHs by three different methods during the Mexico City Metropolitan Area field campaign in April 2003 presents a unique opportunity for characterization of these compounds and assessment of the methods. The three methods are (1) collection and analysis of bulk samples for time-integrated gas- and particle-phase speciation by gas chromatography/mass spectrometry; (2) aerosol photoionization for fast detection of PAHs on particles' surfaces; and (3) aerosol mass spectrometry for fast analysis of size and chemical composition. This research represents the first time aerosol mass spectrometry has been used to measure ambient PAH concentrations and the first time that fast, real-time methods have been used to quantify PAHs alongside traditional filter-based measurements in an extended field campaign. Speciated PAH measurements suggest that motor vehicles and garbage and wood burning are important sources in Mexico City. The diurnal concentration patterns captured by aerosol photoionization and aerosol mass spectrometry are generally consistent. Ambient concentrations typically peak at ~110 ng m−3 during the morning rush hour and rapidly decay due to changes in source activity patterns and dilution as the boundary layer rises, although surface-bound PAH concentrations decay faster. The more rapid decrease in surface versus bulk PAH concentrations during the late morning suggests that freshly emitted combustion-related particles are quickly coated by secondary aerosol material in Mexico City's atmosphere and may also be transformed by heterogeneous reactions.

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