Abstract
Introduction: Naphthalene is a harmful environmental tox reduced in serum and/or airway lining fluid of patients with COPD, asthma, bronchopulmonary dysplasia, silicosis, and post-transplant rejection. Aim of work: This study was done to evaluate the use of serum CC16 level as a biological marker for occupational respiratory diseases in relation to pulmonary function tests among workers exposed to naphthalene in polyvinyl chloride (PVC) manufacture. Material and methods: The study included 33 exposed workers and 33 control subjects. The study groups were subjected to full history taking, clinical examination and pulmonary function testing. Serum levels of CC16 and naphthalene levels measured for both groups. Results: Pulmonary functions parameters (FVC, FEV1, FEV1/FVC, FEF 25%, FEF 50%, FEF 75%), were significantly decreased in the exposed group compared to the control and indicated obstructive ventilatory impairment among the exposed workers. Serum naphthalene was significantly higher, while serum CC16 was significantly lower among the exposed group compared to the control. Exposed smokers exhibited the highest serum naphthalene and the lowest serum CC16 among all study groups. The duration of naphthalene exposure positively correlated with the serum level of naphthalene and negatively correlated with pulmonary functions and the serum level of CC16. Also serum level of CC16 correlated negatively with the serum naphthalene level and smoking index.Conclusion: Occupational exposure to naphthalene in PVC manufacture is associated with obstructive ventilatory impairment, with corresponding decrease in the serumlevel of Clara cell protein (CC16), which can be used as a biomarker for respiratory system affection among workers exposed to naphthalene.