Micronucleus frequency in children exposed to biomass burning in the Brazilian Legal Amazon region: a control case study

The study was conducted during the dry seasons in two regions of the Brazilian Amazon. The assay was carried out on buccal epithelial cells of 574 schoolchildren between 6-16 years old.The results show a significant difference between micronucleus frequencies in children exposed to biomass burning compared to those in a control area.The present study demonstrated that in situ biomonitoring using a sensitive and low cost assay (buccal micronucleus assay) may be an important tool for monitoring air quality in remote regions. It is difficult to attribute the increase in micronuclei frequency observed in our study to any specific toxic element integrated in the particulate matters. However, the contribution of the present study lies in the evidence that increased exposure to fine particulate matter generates an increased micronuclei frequency in oral epithelial cells of schoolchildren.The Amazon extends from the Atlantic Ocean to the eastern slopes of the Andes, with 61% of the area belonging to Brazil, where it is called the Brazilian Amazon. The region has been environmentally affected by advancing economic development, especially agribusiness and ranching. This has provoked changes in land use, resulting in increased deforestation and increased biomass burning in both native forest and pasture areas [1,2]. Several studies show that pasture formation is the main land use in newly deforested regions [3]. Sugar cane is an example of agribusiness that is in rapid expansion in the Amazon biome, driven by the political incentive to produce and consume biofuel both nationally and internationally. Brazil is one of the largest producers of biofuel worldwide, with most production concentrated in the Midwest region. Sugarcane bagasse burning at harvest time is widely practiced in Brazilian production to facilitate harvesting and increase the yield of manual cutting; however, this archaic procedure results in increased pollutant concentrations in the atmosphere [4-7].Biomass bur