Volatile Organic Compounds and Formaldehyde as Explaining Factors for Sensory Irritation in Office Environments

Abstract

This study's database comprised results of volatile organic compound (VOC) measurements from 176 office buildings. In 23 of the 176 buildings, formaldehyde measurements were also conducted. It was suspected that the buildings had indoor air problems, but a walk-through inspection did not reveal any clear, abnormal contaminant sources. The 50 most abundant VOCs and their concentrations in 520 air samples were analyzed. The irritation potency was estimated for 33 out of the 50 common VOCs and their mixtures, as well as for formaldehyde. This information was used to calculate the recommended indoor air levels (RILs) for the VOCs. The RILs were considerably higher than the measured mean indoor air concentrations in the buildings. However, the RIL for formaldehyde was exceeded in most of the 23 buildings studied. According to the evaluation of irritation potency, formaldehyde was a more likely cause of sensory irritation than the mixture of common nonreactive VOCs at the concentrations that occurred in the buildings without abnormal indoor sources. Furthermore, environmental symptoms of office workers were characterized in 20 office buildings (including the database of 176 office buildings) with the aid of an indoor air questionnaire. The most frequent symptoms related to the indoor environment were involved the upper respiratory tract. However, no relationship could be shown between the reported symptoms and the occurrence of VOC and formaldehyde concentrations in these buildings. Generally, the study results indicated that formaldehyde was the more likely agent causing sensory irritation than the mixture of the common nonreactive VOCs at the concentrations occurring in the buildings without abnormal indoor sources.

Keywords:

• indoor air
• irritation potency
• questionnaire

ACKNOWLEDGMENTS

The authors thank the indoor air researchers of FIOH Uusimaa for their field investigations and laboratory work.

Notes

^A Calculation based on correlation findings between the OEL and 0.03 × RD50 reported by Nielsen et al.^{( 17 )} and Alarie et al.^{( 20 )}

^B RD50 value obtained from Nielsen et al.^{( 28 )}

^C Calculated RD₅₀ (ppm) from P⁰: Log RD50 = 2.693 + (0.887*logP⁰). From Alarie et al.^{( 29 )}

^D RD50 value obtained from Schaper^{( 16 )}

^E RD50 value obtained from Pasanen et al.^{( 27 )}

^F RD50 value obtained from Kasanen et al.^{( 24 )}

*Probability for irritation at the mean concentrations (maximum recommended threshold = expected mean concentration/RIL).

**Maximum recommended threshold = expected maximum concentration/RIL.

^A B1, Floor 3: Two VOC measurements, one formaldehyde measurement.

^B B1, Floor 4: The individual VOC values were mean values of five VOC measurements.

^C B2, Floor 2: One VOC measurement. Defective flooring material was found.

^D B3, Floor 7: One VOC measurement, one formaldehyde measurement. Defective flooring material was found.

^E B4, Floor 3: One VOC measurement. The floor had been waxed recently.

^F Calculated according to Nielsen et al.^{( 17 )} and Alarie et al.^{( 20 )}