Sensory and other neurogenic effects of exposures to airborne office dust

This Danish Office Dust Experiment investigated the response of 24 healthy non-sensitive adult subjects to exposure to normal office dust in the air ( 7 mu g m(-3) clean air, 136 and 390 mu g m(-3) TSP). The dust had no major identifiable specific reactive components. The exposure duration was 51/4h and was arranged in a climate chamber in controlled atmospheric conditions. Measurements were made acutely at exposure onset, subacutely at exposure e nd and next day (late). As secondary aims the time course and threshold of any observed effect of the exposures, and the characteristics of any hyperr esponding subgroup were investigated. In a questionnaire with 36 questions the dust exposures caused increased acute, subacute and late perceptions of reduced air quality, acute and subacute increased odor intensity, acute ey e irritation, acute and late heavy head, subacute feeling of perspiration, and subacute general irritation. Cough increased subacutely during exposure s. In addition, a performance test showed effects of dust exposures which a lso affected "Mood Scale" ratings. No effect was seen on an addition test f or distraction, and objective measurements of skin humidity. The overall co nclusion of the study is that healthy subjects without hypersensitivity rea ctions seem to respond to airborne house dust. The responses are both subje ctive sensory reactions and other neurogenic effects even at exposure level s within the range found in normal buildings. Some of the effects appeared acutely and decreased through adaptation while others increased during prol onged exposure and remained for more than 17 h after the exposure ended. Th e findings may indicate for this type of dust a threshold level for the dos e-response relationships below 140 mu g m(-3). (C) 2000 Elsevier Science Lt d. All rights reserved.