ORGANIC DUST EXPOSURE FROM COMPOST HANDLING - RESPONSE OF AN ANIMAL-MODEL

The objective of this investigation was to elucidate the pulmonary res ponses of an animal model to dust generated from leaf/wood compost whi ch had caused a severe case of acute respiratory illness in an individ ual. Guinea pigs were exposed for 4 hr to 30 mg/m3 of aerosolized leaf /wood compost dust. Inhalation resulted in significant cellular activa tion and changes in pulmonary mechanics. Maximal elevation in breathin g rate (up 36%) was observed 12-18 hr postexposure. Similarly, maximal granulocyte infiltration (up 1,600%) and activation of alveolar macro phages (up 65%) occurred 18 hr postexposure. In contrast, maximal airw ay obstruction (up 120%) occurred immediately after exposure and retur ned toward normal (up 53%) by 18 hr postexposure. In several respects, the airway obstruction and pulmonary inflammation described in the an imal model were comparable to the human response to compost dust. Ther efore, this animal model may be useful in predicting the potential res piratory hazard associated with exposure to various organic dusts. (C) 1993 Wiley-Liss, Inc.