evaluation of bronchial response among occupationally exposed vulcanizers in calabar municipality, cross river state -nigeria

Introduction: histamine directly interacts with airways smooth muscles to initiate contraction. this occurs even at low concentrations among individuals predisposed to increased airway inflammation and asthma. methods: a digital vitalograph, nebulizer, histamine, and pulse oximeter were used in this research. a total of one hundred and sixty subjects were selected and categorized into two groups; group 1 (test subject) and group 2 (control), each group contained eighty (80) subjects. group 1 comprised occupationally exposed vulcanizers and group 2 comprised selected students from the university of calabar as control. both groups comprised young male subjects of equal age (20-40 years), devoid of pre-existing respiratory disorders or on any medication(s). demographic parameters were used to obtain sufficient information for overall analysis. lung parameters (fvc, fev1, pefr, and fev1%) were evaluated using a vitalograph spirometer. results: basal measurement showed that group 1 had a moderate decrease in lung volumes (fvc, fev1, pefr, and fev1%) of 65 subjects (representing 81.25%) and a mild decrease in 15 subjects (18.75%); all the subjects in group 2 showed a mild decrease in lung volumes. inhalation of histamine mist of different concentrations showed that group 1 had a severe decrease in lung volumes of 70 subjects (87.5%) and a mild decrease in 10 subjects (12.5%). all subjects in group 2 showed a mild decrease in lung volumes. conclusion: histamine provocative test helps to evaluate asthma signs and symptoms. airways hyper reactiv-ity is associated with inflammation as a consequence of airway hyperreflexia. it is evidenced that associated pollutants and their chronic inhalation by the vulcanizers have a retrogressive impact on their airways which manifests with hyper response an indication for asthma signs.