Mutation Research/Reviews in Mutation Research
ReviewToxicological assessment of ambient and traffic-related particulate matter: A review of recent studies
Section snippets
Particulate air pollution and traffic
Epidemiological studies have demonstrated that exposure to urban particulate matter (PM) is associated with several adverse health effects. Long-term exposure to high concentrations of PM increases the risk of lung cancer, respiratory diseases and arteriosclerosis, whereas short-term exposure peaks can cause exacerbation of several forms of respiratory diseases, including bronchitis and asthma, as well as changes in heart rate variability [1], [2], [3]. The results of epidemiological studies on
Methodological approach
In Pubmed, we searched for publications on ambient PM, PM10, PM2.5, particulates or fine dust in combinations with the search terms traffic, diesel, mutagenicity, cytotoxicity, DNA-reactivity, adducts, oxidative damage, radical formation, metals, elemental composition, PAH, nitro-PAH, quinones and semi-quinones. As we aimed to review the literature on ambient PM samples specifically, results from studies evaluating toxicity and chemical composition of diesel exhaust particles (DEP), or other PM
Chemical characteristics and radical generating capacity of PM
Ambient PM contains biological material, organic compounds, hydrocarbons, acid aerosols and metals absorbed or attached to a carbonaceous core. The TSP and PM10 fractions consist primarily of crustal materials, sea salt and biological factors (including bacteria and pollen) and are generated by mechanical processes rather than combustion. On the other hand, PM2.5 and ultra fine particulates are predominantly produced by combustion processes and consist primarily of metals, hydrocarbons and
Mutagenicity of PM
The Ames mutagenicity test is a short-term in vitro assay that has frequently been used to establish the mutagenicity of ambient and indoor PM [31], [65], [66]. Short-term mutagenicity assays in general can detect the genotoxic effect of either single chemical and physical agents or heterogeneous mixtures, such as ambient PM. As some PAH and other organic molecules require metabolic activation in order to exert their mutagenic activity, metabolising enzymes from rat liver microsomes or S9, are
Cytotoxicity of different PM size fractions
Several different methods have been used to establish the cytotoxicity of PM. The most important distinctions between these tests are the use of various cell types and the time of incubation, varying from 4 to 72 h. Also, different PM fractions and extraction procedures have been used. These differences and variables should be taken into account when results from different studies are compared.
Table 4 shows the results of the most recent studies on the cytotoxicity of PM. Three out of seven
DNA-reactivity of different PM size fractions
Generally, two types of DNA-reactivity have been studied in order to characterise PM genotoxicity, which either focus on the analysis of DNA-adduct formation or on oxidative DNA damage. The latter can be measured either as induction of DNA strand breaks in for instance the Comet assay or as the formation of 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxodG). The summary presented in Table 5, shows that ten out of eighteen studies demonstrated positive dose–response curves of PM-induced
Chemical composition of specific PM size fractions
Information on particle size distribution is essential to understand the potential health effects of PM exposure. Although there is no strict relation between size distribution and sources of emission, it has been demonstrated that different PM size fractions originate from different types of PM sources and that the chemical speciation and bioavailability of PM components also depend on the source of emission. In order to evaluate differences in chemical composition and toxicological
Final remarks and conclusions
Epidemiological studies have provided ample evidence of a positive association between PM exposure and the induction of serious adverse health effects. As no threshold for PM induced health effects has been established up to now, a certain level of impact of PM on human health probably has to be accepted. Current policies in the EU might lead to reductions of the emissions of PM in general, but current EU standards are only defined for PM10 (annual average of 40 μg/m3; daily average of 50 μg/m3,
References (103)
- et al.
Linking exposure to environmental pollutants with biological effects
Mutat. Res.
(2003) - et al.
Health effects of particles in ambient air
Int. J. Hyg. Environ. Health
(2004) Fine particles and human health—a review of epidemiological studies
Toxicol. Lett.
(2004)- et al.
Quinoid redox cycling as a mechanism for sustained free radical generation by inhaled airborne particulate matter
Free Radic. Biol. Med.
(2001) - et al.
Particulate matter, PM 10 & PM 2.5 levels, and airborne mutagenicity in Chiang Mai, Thailand
Mutat. Res.
(2002) - et al.
Elemental characterization of PM10, PM2.5 and PM1 in the town of Genoa (Italy)
Chemosphere
(2006) - et al.
Polycyclic aromatic hydrocarbons in ambient air particles in the city of Las Palmas de Gran Canaria
Environ. Int.
(2003) - et al.
Noninvasive detection of hydroxyl radical generation in lung by diesel exhaust particles
Free Radic. Biol. Med.
(2001) - et al.
The role of metals in site-specific DNA damage with reference to carcinogenesis
Free Radic. Biol. Med.
(2002) - et al.
The genotoxicity of ambient outdoor air, a review: Salmonella mutagenicity
Mutat. Res.
(2004)