Composição do Ar e Sintomas da Asma.

O texto abaixo publicado abaixo é de interesse para a compreensão do impacto da composição do ar e de sintomas em asmáticos. Agradecemos os 33 participantes que preencheram os questionários duas vezes por dia durante dois meses e, realizaram as provas de função respiratória como também a equipe do HU que montou a estação para determinação de poluentes.

Association between ionic composition of fine and coarse aerosol soluble fraction and peak expiratory flow of asthmatic patients in Sao Paulo city (Brazil) de Christine Bourotte, Ana-Paula Curi-Amarante, Maria-Cristina Forti, Luiz A. A. Pereira, Alfesio L. Braga, Paulo A. Lotufo publicado em Atmospheric Environment 41 (2007) 2036–2048. Trata-se da junção do projeto de pós-doutorado de Christine Bourotte e do doutorado de Ana Paula Curi (supervisionada e orientada, respectivamente por esse blogueiro) com financiamento da FAPESP (01/13945-6 e 02/04789-3). O estímulo à realização da pesquisa deve-se a Adolpho José Melfi e à Paulo Hilário Nascimento Saldiva.

Abstract Air pollutants are associated with adverse respiratory effects mainly in susceptible groups. This study was designed to assess the impact of the ionic composition of particulate matter on asthmatic respiratory functions in Sao Paulo city. From May to July 2002, fine and coarse particulate matter fractions were collected and their respective chemical composition with respect to major ions (Na+, Mg2+, K+, Ca2+, NH4 +, Cl_, NO3_ and SO4 2 _) were etermined in each aqueous-extract fraction. The results showed predominant concentrations of SO4 2 _ (48.4%), NO3_ (19.6%) and NH4 + (12.5%) in the fine fraction, whereas NO3_ (35.3%), SO4 2 _ (29.1%), Ca2+ (13.1%) and Cl_ (12.5%) were the predominant species in the coarse fraction. The association between the chemical components of both fractions and the daily peak expiratory flow (PEF) measurements (morning and evening) of the 33 asthmatic individuals were assessed through a linear mixed-effects model. The results showed a significant negative correlation (decrease of PEF) between morning PEF and coarse chloride (3-day moving average) and between evening PEF and coarse Na+ (3-day moving average), coarse Mg2+ (3-day moving average) and coarse NH4+ (2- and 3-day moving average). A significant negative correlation has also been observed between morning and evening PEF and Mg2+ in the fine fraction. These results suggest that some particle chemical constituents may increase the responsiveness of airways and that coarse particles that deposit in the upper airways may be more relevant for asthmatic response and irritation. However, the results do not prove a clear causal relationship.