Measurement of volatile organic compounds (VOCs) in new residential buildings and VOCs behavior over time.

For the purpose of the investigation of characteristics of VOCs found indoors in recently constructed residential buildings, we measured the behavior of VOCs which were sampled at one-month intervals over a period of one year from the, initial occupancy date in both a detached house and an apartment in a multiple' dwelling. At the first passive sampling from the wooden detached residential building, n-hexane, n-undecane, toluene, ethylacetate, methylethylketone, alpha-pinene and (+)-limonene were present in relatively high concentrations of 10 ppb or higher in the living room. Then these VOCs showed a declining trend with time. p-Dichlorobenzene showed an extremely high concentration (approx. 320 ppb) in June, which subsequently declined with each passing month. There is a high possibility that the cause was the use of a pesticide containing p-dichlorobenzene during the period of changeover from winter to summer clothes in June. On the other hand, from the multiple dwelling, four VOCs showed values of 10 ppb or more (toluene, 1,2,4-trimethylbenzene, methylethylketone and alpha-pinene). Of these VOCs, methylethylketone concentration was in excess of 100 ppb, and then also showed a declining trend with time. Even for new residential buildings completed during the same time frame, it was shown that the types of VOC contaminants and their concentrations varied significantly.