Abstracts: ISEE 22nd Annual Conference, Seoul, Korea, 28 August–1 September 2010: Indoor and Built Environment
Among the large variety of gaseous indoor pollutants, formaldehyde has always had an exceptional position. In recent years, many countries and organizations have developed concepts for the evaluation of indoor air quality. At present, a number of highly visible, indoor-related formaldehyde guidelines exist worldwide, but the problem is that different criteria are applied by different bodies.
In this study, available guideline values are critically compared and discussed. Guidelines are generally based on toxicological or statistical criteria. Health-related values can be roughly categorized into 2 groups based on exposure durations. The short-time levels are used for preventing acute effects on individuals, whereas long-term levels are used for preventing the chronic effects of formaldehyde. The statistical evaluation requires representative data sets.
Formaldehyde allowable concentrations proposed by guidelines continuously decreased with time, but current recommendations range from approximately 0.001–0.15 ppm. It is, however, interesting to note that Germany and the World Health Organization recently confirmed their values of 0.1 ppm (from 1977) and 0.08 ppm (from 1987), respectively. Emission of formaldehyde from building products and consumer goods has also been limited by authorities and by voluntary criteria. An evaluation of recent emission studies and indoor surveys carried out in industrialized countries has demonstrated that the situation has improved due to the efforts done over recent decades. An examination of international studies indicates that the average exposure of the population to formaldehyde seems to lie generally below 0.05 ppm and it seems questionable whether formaldehyde concentrations lower than 0.02 ppm can be permanently achieved under normal living conditions.
No one will reasonably doubt that formaldehyde is a relevant indoor pollutant. Regulations are urgently required, but it should be discussed if the lower guideline value is always the most appropriate one. Focusing too much on a single compound could also be counterproductive for human health.