Saf Health Work.  2011 Dec;2(4):355-364.

Odor Thresholds and Breathing Changes of Human Volunteers as Consequences of Sulphur Dioxide Exposure Considering Individual Factors

• Kleinbeck
• SchAper M
• Juran SA
• Kiesswetter E
• Blaszkewicz M
• Golka K
• Zimmermann A
• BrUning T
• Van Thriel C

Abstract

OBJECTIVES
Though sulfur dioxide (SO2) is used widely at workplaces, itseffects on humans are not known. Thresholds are reportedwithout reference to gender or age and occupational exposure limits are basedon effects on lung functioning,although localized effects in the upper airways can be expected.This study's aim is to determine thresholds with respect to age and gender and suggests a new approach to risk assessment using breathing reflexes presumably triggered by trigeminal receptors in the upper airways.
METHODS
Odor thresholds were determined by the ascending method of limits in groups stratified by age and gender.Subjects rated intensities of different olfactory and trigeminal perceptions at different concentrations of SO2. During the presentation of the concentrations, breathing movements were measured by respiratory inductive plethysmography.
RESULTS
Neither age nor gender effects were observed for odor threshold. Only ratings of nasal irritation were influenced bygender. A benchmark dose analysis on relative respiratory depth revealed a 10%-deviation from baseline at about 25.27 mg/m3.
CONCLUSION
The proposed new approach to risk assessment appearsto be sustainable. We discuss whether a 10%-deviation of breathingdepth is relevant.

Keyword

Risk assessment; Respiratory mechanics; Sensory thresholds; Sulfur dioxide

MeSH Terms

Human Experimentation
Humans
Lung
Occupational Exposure
Odors
Reflex
Respiration
Respiratory Mechanics
Risk Assessment
Sensory Thresholds
Sulfur Dioxide
Sulfur Dioxide