Ambient Levels of Air Pollution Induce Goblet-Cell Hyperplasia in Human Conjunctival Epithelium Priscila Novaes,1 Paulo Hilário do Nascimento Saldiva,2 Newton Kara-José,1 Mariângela Macchione,2 Monique Matsuda,1,2 Lourdes Racca,3 and Alejandro Berra1,3 1Laboratório de Investigação em Oftalmologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brasil; 2Laboratório de Poluição Atmosférica Experimental, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brasil; 3Laboratorio de Investigaciones Oculares, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina Abstract Background: Ocular mucosa is exposed constantly to the external environment, and chronic exposure to air pollution may affect the ocular surface. Objective: We assessed the effect of air pollution on the ocular surface by combining determinations of individual exposure and conjunctival impression cytology. Methods: A panel study was conducted with 29 volunteers recruited in two locations with different pollution levels: São Paulo (n = 13) and Divinolândia (n = 16) . We assessed mean individual levels of nitrogen dioxide (NO2) exposure for 7 days, using a passive sampler. Impression cytology samples were obtained from inferior tarsal conjunctiva. Comparisons between the two groups in terms of NO2 exposure and goblet-cell counts were performed using the Student t-test. Correlations between goblet-cells counts and corresponding individual NO2 exposure levels were determined using Spearman's correlation. Results: Individuals living in São Paulo received a significantly (p = 0.005) higher dose of NO2 (mean 32.47 ; SD 9.83) than those living in Divinolândia (mean 19.33 ; SD 5.24) . There was a steady increase in goblet-cell counts, proportional to NO2 exposure (Spearman's correlation = 0.566, p = 0.001) , with a dose–response pattern. Conclusions: A positive and significant association between exposure to air pollution and goblet-cell hyperplasia in human conjunctiva was detected. The combination of simple measurements of exposure and impression cytology was an effective and noninvasive approach for characterizing human response to ambient levels of air pollution. Key words: air pollutants, conjunctiva, environmental, goblet-cell, impression cytology, nitrogen dioxide. Environ Health Perspect 115:1753–1756 (2007) . doi:10.1289/ehp.10363 available via http://dx.doi.org/ [Online 14 September 2007] Address correspondence to P. Novaes, R. Manoel da Nóbrega, 1240 Apt. 61-A, Cep: 04001-004, São Paulo, Brazil. Telephone: (5511) 3061-7688, (5511) 3891-2131. Fax: (5511) 3068-0072. E-mail: pris_novaes@yahoo.com.br We especially thank M.C. Machado and E. Giantomassi for their support and help in selecting the subjects and allowing us the use of the facilities at Divinolândia General Hospital (CONDERG) , Divinolândia, Brazil. The authors declare they have no competing financial interests. Received 14 April 2007 ; accepted 13 September 2007. The full version of this article is available for free in HTML or PDF formats. |