Urban air pollution induces micronuclei in peripheral erythrocytes of mice in vivo.
In this study, we explored the role of chronic exposure to urban air pollution in causing DNA damage (micronuclei frequency in peripheral erythrocytes) in rodents in vivo. Mice (n=20) were exposed to the urban atmosphere of São Paulo for 120 days (February to June 1999) and compared to animals (n=20) maintained in the countryside (Atibaia) for the same period. Daily levels of inhalable particles (PM10), CO, NO(2), and SO(2), were available for São Paulo. Occasional measurements of CO and O(3) were made in Atibaia, showing negligible levels of pollution in the area. The frequency of micronuclei (repeated-measures ANOVA) increased with aging, the highest values obtained for the 90th day of experiment (P<0.001). The exposure to urban air pollution elicited a significant (P=0.016) increase of micronuclei frequency, with no significant interaction with time of study. Associations (Spearman's correlation) between pollution levels of the week that precede blood sampling and micronuclei counts were observed in São Paulo. The associations between micronuclei counts and air pollution were particularly strong for pollutants associated with automotive emissions, such as CO (P=0.037), NO(2) (P<0.001), and PM10 (P<0.001). Our results support the concept that urban levels of air pollution may cause somatic mutations.
Soares
S R C
SR
Laboratory of Experimental Air Pollution, Faculty of Medicine, Department of Medicine, School of Medicine, University of São Paulo, Av. Dr. Arnaldo 455, SP CEP 01246-903, São Paulo, Brazil.
Bueno-Guimarães
H M
HM
Ferreira
C M
CM
Rivero
D H R F
DH
De Castro
I
I
Garcia
M L B
ML
Saldiva
P H N
PH
D000280:Administration, Inhalation; D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D001938:Brazil; D004305:Dose-Response Relationship, Drug; D004912:Erythrocytes / Q000187:drug effects* / Q000648:ultrastructure; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D048629:Micronuclei, Chromosome-Defective / Q000187:drug effects / Q000648:ultrastructure; D015162:Micronucleus Tests; D014504:Urban Health; D001335:Vehicle Emissions / Q000633:toxicity
D000393:Air Pollutants; D001335:Vehicle Emissions