Clinical and histopathological changes of the nasal mucosa induced by occupational exposure to sulphuric acid mists

• Published in: Occupational and environmental medicine (London, England) Vol. 60; no. 6; pp. 395 - 402
• Main Authors: Grasel, S S, Alves, V A F, da Silva, C S, Cruz, O L M, Almeida, E R, de Oliveira, E
• Format: Journal Article
• Language: English
• Published: London BMJ Publishing Group Ltd 01.06.2003; BMJ Publishing Group; BMJ; BMJ Publishing Group LTD; BMJ Group
• Subjects: Acids; Adult; Age; Air Pollutants, Occupational - adverse effects; Anodic oxidation; Biological and medical sciences; Biopsy; Brazil; Cancer; Chemical and industrial products toxicology. Toxic occupational diseases; Chemical hazards; Control groups; Cross-Sectional Studies; Epithelium; Gas, fumes; Health aspects; Histology, Pathological; histopathology; Humans; Lesions; Logistic regression; Male; Medical sciences; Metallurgy; Metals; Middle Aged; Mucosa; Nasal mucosa; Nasal Mucosa - drug effects; Nasal Mucosa - pathology; Nose; Nose Diseases - chemically induced; Nose Diseases - pathology; Occupational Diseases - chemically induced; Occupational Diseases - pathology; Occupational exposure; Occupational Exposure - adverse effects; Original; Physiological aspects; Regression Analysis; Septum; Statistical analysis; Sulfuric acid; Sulfuric acids; Sulfuric Acids - adverse effects; sulphuric acid; Toxicology; Workers; Workplaces; Brazil; Human; Histopathology; Toxicity; Mucosa; Nose; Aerosols; Occupational exposure; Occupational medicine; Sulfuric acid
• ISSN: 1351-0711; 1470-7926
• DOI: 10.1136/oem.60.6.395

Aims: To assess potential alterations of the nasal mucosa by clinical and histopathological evaluation of workers exposed to sulphuric acid mists at anodising plants, correlating the findings with duration of exposure and sulphuric acid concentrations in the air, and comparing them with a control group. Methods: Fifty two workers from five plants underwent a clinical evaluation (standard questionnaire, clinical, and ear, nose, and throat examination including nasal endoscopy). For the histopathological study, 20 of the 52 subjects (study group) were randomly selected, as well as 11 unexposed subjects (control group), matched by sex, age, and smoking habits. Nasal biopsy specimens were obtained from the anterior septum mucosa and the anterior curvature of the middle turbinate in each individual. A total of 56 nasal mucosa specimens (37 in the study group and 19 in the control group) were evaluated with regard to normal respiratory epithelium or metaplastic epithelium, atypia or dysplasia, and alterations of the lamina propria. Results: The histopathological study revealed squamous metaplasia in 29 (79%) and atypia in 13 (35%) of the 37 study group samples. No association was found between exposure duration and the clinical and histopathological variables, but a significant association was found between sulphuric acid concentrations higher than 200 μg/m3 and pale mucosal patches and ulcerations in the exposed subjects. Logistic regression analysis showed that the exposed subjects had a fivefold risk of developing atypia compared with the unexposed subjects. Conclusions: Workers exposed to sulphuric acid mists presented with a high incidence of nasal symptoms, and macroscopic and microscopic changes of the nasal mucosa, including squamous atypia and dysplasia. The risk for these histopthological lesions increased with higher sulphuric acid concentrations in the air, revealing an exposure-response relation.