Does exposure to air pollutants cause hospitalization for respiratory diseases?

Luiz Fernando Costa Nascimentoa,*
*Corresponding author. E-mail: luiz.nascimento@pq.cnpq.br (L.F.C. Nascimento).
aUniversidade de Taubaté, Taubaté, SP, Brazil. 

A study conducted at Universidade de Taubaté, in Taubaté, São Paulo, aimed to identify an association between exposure to air pollutants (more specifically fine particulate matter) and hospitalizations for respiratory diseases in children aged up to 10 years. The researchers found an association between exposure to this material and an increased risk of hospitalization for girls, but not a significant one for boys.

Girls younger than 10 years exposed to fine particulate matter – a mixture of liquid and solid particles suspended in the air with a diameter smaller than 2.5 μm whose composition and size depend on the emission source1 – had a higher risk of hospitalization for respiratory diseases than boys of the same age group.

This was the conclusion of the researchers from Universidade de Taubaté, in Taubaté, São Paulo, who analyzed data on the hospitalization of children younger than 10 years living in the city of Cuiabá, capital of Mato Grosso – state in the Amazon Region with a high number of fire outbreaks –, from January 2012 to December 2013. In this period, 1,165 children were hospitalized – 640 males and 525 females –, and the Center for Weather Forecasting and Climate Studies of the National Institute for Space Research estimated the data on pollutants.

The researchers declare that there is strong evidence that exposure to fine particulate is usually associated with respiratory diseases. These particles include sulfates, nitrates, acids, metals, and carbon particles with various chemicals adsorbed on their surfaces. Compared to the coarse fraction of particulate matter (those with diameter between 2.5 and 10 μm), the fine particulate penetrates more easily inside the house, travels longer distances, and due to its size, it can reach deeper lung structures.2

The reason for the different responses to exposure to air pollutants between girls and boys is still not well established. Studies suggest that health responses to air pollution could differ between women and men, and between girls and boys, but it is not yet clear whether the response observed is a result of biological differences related to gender or differences in activity patterns, co-exposure, or even accuracy in exposure measurement. Possibly, these differences consist of some combination of two factors – exposure patterns and biological response.3-5

The researchers concede that the study has limitations, as they used data estimated by mathematical modeling in the analysis, and also by the lack of information about the housing conditions of the children assessed. However, even with these possible limitations, they could identify the role of exposure to fine particulate matter in the hospitalization of female children, which suggests that this type of stratification by gender should be adopted in further studies, as the analysis involving both genders was not significant. 

REFERENCES
  1. Slaughter JC, Kim E, Sheppard L, Sullivan JH, Larson TV, Claiborn C. Association between particulate matter and emergency room visits, hospital admissions and mortality in Spokane, Washington. J Expo Anal Environ Epidemiol. 2005;15(2):153-9. https://doi.org/10.1038/sj.jea.7500382
  2. Pope CA. Epidemiology of fine particulate air pollution and human health: biologic mechanisms and who’s at risk? Environ Health Perspect. 2000;108(Supl. 4):713-23. https://dx.doi.org/10.1289%2Fehp.108-1637679
  3. Clougherty JE. A growing role for gender analysis in air pollution epidemiology. Ciênc Saúde Coletiva. 2011;16(4):2221-38. http://dx.doi.org/10.1590/S1413-81232011000400021
  4. Miller KA, Siscovick DS, Sheppard L, Shepherd K, Sullivan JH, Anderson GL, et al. Long-term exposure to air pollution and incidence of cardiovascular events in women. N Engl J Med. 2007;356(5):447-58. https://doi.org/10.1056/NEJMoa054409
  5. Tuan TS, Venâncio TS, Nascimento LF. Effects of Air Pollutant Exposure on Acute Myocardial Infarction, According to Gender. Arq Bras Cardiol. 2016;107(3):216-22. https://doi.org/10.5935/abc.20160117

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