Increase in exhaled nitric oxide in shoe and leather workers at the end of the work-shift

Measurement of nitric oxide (NO) in exhaled air is a non-invasive procedure for assessing airway or pulmonary inflammation, and for evaluating environmental irritant effects of air pollution. The objective of this study was to evaluate exhaled NO levels in synthetic leather workers exposed to organic solvents toluene, xylene and methylethyl ketone.

Seventeen shoe and leather workers and 10 controls from administrative personnel of the factory were studied. The levels of exhaled NO at baseline and at the end of the work shift were measured using a standardized chemiluminescence technique. Environmental assay of the three solvents was also assessed during the working day.

Environmental solvent concentrations were high but within permissible exposure levels. Exhaled NO concentrations increased by 40% in the leather workers at the end of the working day from a mean +/- SD of 9.1 +/- 1.3 p.p.b. to 12.8 +/- 1.7 p.p.b. (P < 0.02), as compared to the controls.

Exhaled NO is increased in shoe and leather workers exposed to solvents at the end of work shift, while it does not change in unexposed subjects of the same factory. Exhaled NO may be a sensitive tool to monitor sub-clinical effects of occupational pro-inflammatory substances.