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ARTICLES: Gabriele Renzetti, Gaetano Silvestre, Claudio D'Amario, Egidio Bottini, Fulvia Gloria-Bottini, Nunzio Bottini, Alexander Auais, Miriam K. Perez, and Giovanni Piedimonte Less Air Pollution Leads to Rapid Reduction of Airway Inflammation and Improved Airway Function in Asthmatic Children Pediatrics 2009; 123: 1051-1058 [Abstract] [Full text] [PDF]

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Air pollution does not influence eosinophils count in peripheral blood.

Giuseppe Lippi, Martina Montagnana, Massimo Franchini, Gian Cesare Guidi   (14 April 2009)

Air pollution does not influence eosinophils count in peripheral blood. 14 April 2009
Giuseppe Lippi, Associate Professor of Clinical Biochemistry Sez. Chimica Clinica, Università di Verona, Osp. Policlinico, 37134 - Verona, Italy, Martina Montagnana, Massimo Franchini, Gian Cesare Guidi Send letter to journal: Re: Air pollution does not influence eosinophils count in peripheral blood. giuseppe.lippi{at}univr.it Giuseppe Lippi, et al.	We read with interest the recent article of Renzetti et al, who concluded that nasal eosinophils are sensitive indicators of polluted rural environment in allergic asthmatic children (1). To further assess the relationship between air pollution and eosinophils count in peripheral blood, which is a widespread, easy and inexpensive laboratory test, we analyzed data of 511 consecutive, unselected, young outpatients (258 females and 253 males, median age [5-95th percentile distribution]: 10 [3- 18] years), who underwent routine haematological testing between 1st January 2009 and 8th April 2009 at the outpatient clinic of the clinical chemistry and hematology laboratory at the University Hospital of Verona. In all children peripheral venous blood was collected by venipuncture between 8 and 10 AM. Eosinophils count was assayed on ADVIA 2120TM (Bayer Diagnostics, Newbury, Berkshire, UK). Daily data on air pollution and Particulate Matter <10 µm (PM10) concentration (24-hour averages) of the Verona district were retrieved from the official website of Agenzia Regionale per la Prevenzione e Protezione Ambientale del Veneto (ARPAV). A 50 µg/m3 cutoff for PM10 was chosen, which is in agreement with the current 24-hour limit value for the protection of human health from air pollution as currently established by the European Union (2). Significance of differences and frequency distribution of values were assessed by the Wilcoxon Mann-Whitney and Chi Square tests (for categorical variables). Statistical analyses were performed using the statistical package SPSS- version 17. Results were finally expressed as median and 5-95th percentile distribution. P<0.05 were considered statistically significant. After stratifying children’s data according to the 50 µg/m3 cutoff for PM10, no significant differences were observed between days when the 24-hour levels of PM10 were above or below such limit (0.21 [0.05-0.65] versus 0.19 [0.05-0.67] x(10^6)/L; p=0.143). Accordingly, the percentage of children with eosinophils count above the upper limit of the reference range (0.45x(10^6)/L) was not statistically different between days when the 24-hour levels of PM10 were above or below the 50 µg/m3 threshold for PM10 (17 versus 12%; p=0.217). Taken together these results suggest that nasal eosinophils might be a better parameter than eosinophils count in peripheral blood for assessing air pollution-induced airway inflammation in children. References 1. Renzetti G, Silvestre G, D'Amario C, Bottini E, Gloria-Bottini F, Bottini N, Auais A, Perez MK, Piedimonte G. Less air pollution leads to rapid reduction of airway inflammation and improved airway function in asthmatic children. Pediatrics. 2009 Mar;123(3):1051-8. 2. The Council Of The European Union. Council Directive 1999/30/EC of 22 April 1999 relating to limit values for sulphur dioxide, nitrogen dioxide and oxides of nitrogen, particulate matter and lead in ambient air. Available at: http://europa.eu/scadplus/leg/en/lvb/l28098.htm. Last access: 13 April 2009. Conflict of Interest: None declared