Genetic instability in plants associated with vehicular traffic and climatic variables

• A method of assessing atmospheric pollution using plant micronuclei as an indicator.
• Micronuclei in T. pallida, vehicle traffic and climatic variations over three years.
• Climatic factors also influenced micronucleus formation in Tradescantia.
• The climatic factors could be a useful biomonitor for the assessment of air quality.
• Low relative humidity and temperature increases the frequency of micronuclei.

To characterize the effect of vehicular traffic on air quality, the micronuclei of Tradescantia pallida tetrads were counted. Young inflorescences of T. pallida (Rose) D.R. Hunt var. purpurea were collected in 2010, 2011, and 2012, from three sites subjected to different intensities of vehicular traffic. The sites were located in the municipality of Dourados, in the State of Mato Grosso do Sul, Brazil. A standardized methodology was used to analyze the Tradescantia micronuclei, in order to evaluate the mutagenic potential of the local air pollutants. Statistical analyses using the Pearson's linear correlation were employed to determine the relationship between relative humidity and temperature, and the average number of micronuclei. In this study, an increase in the average number of passing vehicles was correlated with an increase in the frequency of micronucleus formation. Climatic factors also influenced micronucleus formation, although vehicular traffic remained the most important factor. Thus, the Tradescantia micronuclei assay may be a useful method of assessing air quality.