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Experimental Methods of Dust Charging and Mobilization on Surfaces with Exposure to Ultraviolet Radiation or Plasmas
Published on: April 3, 2018
The effect of air change rate and temperature on phthalate concentration in house dust
Jingjing Pei1, Yahong Sun1, Yihui Yin1
1Tianjin Key Laboratory of Indoor Air Environmental Quality Control, School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China.
Abstract:
Semi-volatile organic compounds (SVOCs) are one of the main indoor pollutant categories. Six phthalates (dimethyl phthalate (DMP), diethyl phthalate (DEP), di(isobutyl) phthalate (DiBP), di(nbutyl) phthalate (DnBP), butyl benzyl phthalate (BBzP) and di(2-ethylhexyl) phthalate (DEHP)) in house dust samples were measured in forty residential apartments in Tianjin and Urumqi in four seasons throughout a year. The measured DEHP dust-phase concentration is in the range: 11.9-699.9 μg/g; and showed obvious differences in different seasons, and the maximum can be 2 times higher than minimum. The DiBP and DnBP showed similar phenomenon. The corresponding gas-phase concentration is estimated considering the influencing factors of indoor temperature, air change rate, particle concentration. Then the dust-gas partition coefficient Kd under different season was obtained through the measured dust-phase concentration and estimated gas-phase concentration. From winter to summer, because the increased temperature leads to higher emission rate, the gas-phase concentration is obviously high in spite of the higher air change rate in summer. The estimated DEHP gas-phase concentration showed obvious differences in different seasons, and the maximum can be about 2 times higher than minimum. The DiBP and DnBP showed similar phenomenon. The lower dust-phase concentration in summer is observed due to the temperature-dependency of the dust-gas partition coefficient. Therefore temperature has the greatest impact on the dust concentration, not influence via emission rate, but influences the partition coefficient Kd.
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