PRESENT STATUS OF THE INDOOR AIR CHEMICAL POLLUTION IN JAPANESE HOUSES BASED ON THE NATIONWIDE FIELD SURVEY FROM 2000 TO 2005

The purpose of this investigation is to know the present status of indoor air chemical pollution byVOCs in Japanese houses. The concentrations of formaldehyde, toluene, xylene, ethyl-benzene,styrene and acetaldehyde were measured in ten thousand built houses from 2000 to 2005. And thefollowing results were obtained. In 2000, the indoor concentrations of formaldehyde exceeded theguideline established by the Ministry of Health, Labor and Welfare of Japanese Government at thepercentage of 27%. And In the case of toluene the percentage was 12 %. The percentages of the otherVOC was quite lower than the guidelines with the exception of the case of acetaldehyde. After that theconcentrations of formaldehyde decreased and the average concentrations became enough lower thanthe guideline. Most of the concentrations of the other VOCs also decreased. The declarations wereshown in every region, in houses with all types of structures.