Toxicity measurements in aqueous solution during ozonation of mono-chlorophenols.
The Microtox toxicity and Oxygen Uptake Rate (OUR) inhibition tests were conducted to monitor the variation of toxicity during ozonation of 2-chlorophenol (2-CP), 3-chlorophenol (3-CP) and 4-chlorophenol (4-CP) under neutral conditions. The results revealed that the oxidized 2-CP solution exhibited new toxicity to pure bacteria and mixed microorganisms in the early stage of ozonation. The largest inhibition of OUR appeared at one mol of applied ozone dosage per mol of initial 2-CP, and the percentage of inhibition was 63.8%. In addition, ozonated 3-CP and 4-CP also significantly induced new aqueous toxicity, if these toxic intermediates were not further ozonated. Comparing the variation of toxicity and the hydroxylated/chlorinated intermediates formed, 3-chloro-catechol, 2-chloro-2, 4-hexadienedioic acid and the dimmer compounds may be related to the sources of toxicity during the ozonation of 2-CP.
Shang
Neng-Chou
NC
Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Rd., Taipei, Taiwan, ROC. shangnc@ntu.edu.tw
Yu
Yue-Hwa
YH
Ma
Hwong-Wen
HW
Chang
Cheng-Hsin
CH
Liou
Ming-Long
ML
D002733:Chlorophenols / Q000737:chemistry* / Q000633:toxicity*; D010100:Oxygen / Q000378:metabolism; D010126:Ozone / Q000737:chemistry*; D010776:Photobacterium / Q000187:drug effects; D012722:Sewage; D012996:Solutions; D014873:Water Pollutants / Q000633:toxicity*
D002733:Chlorophenols; D012722:Sewage; D012996:Solutions; D014873:Water Pollutants; D010126:Ozone; D010100:Oxygen