Toxicity testing of effluent from the UV/H2O2 treatment of polychlorinated biphenyls (PCBS) in water matrix

• Main Author: Yu, Dennis N.
• Format: text
• Language: English
• Published: Animo Repository 2006
• Subjects: Polychlorinated biphenyls; Toxicity testing; Water pollution; Chemical Engineering
• Online Access: https://animorepository.dlsu.edu.ph/etd_masteral/3563; https://animorepository.dlsu.edu.ph/context/etd_masteral/article/10401/viewcontent/CDTG004346_P.pdf
• Institution: De La Salle University

The Asian Regional Research Programme on Environmental Technology Phase II De La Salle University (ARRPET II DLSU) has developed a sequential chemical-biological treatment for PCBs in water. The chemical process is carried out using the UV/H2O2 system while the biological process involves a three-phase fluidized bed reactor utilizing the biodegrading capacity of biofilm. The effluent from the first phase of the treatment may contain unknown chemical compounds produced as a result of the UV/H2O2 treatment. To examine the toxicity of the effluent, three types of toxicity tests were employed: an algal (Scenedesmus bijugatus), a duckweed (Lemna paucicostata) and a mungbean seed (Vigna radiata (L.) Wilchzek) test. Results from the algae bioassay show that EC50 values ranged from 3.68 % - 71.54 %, while the NOAEC and LOAEC values ranged from 2.5 % - 50 % and 5 % - 100 % respectively. The duckweed bioassay revealed the EC50 to range from 36.03 % - 97.35 %, while the NOAEC and LOAEC values ranged from 12.5 % - 40 % and 25 % - 100 %, respectively. In most of the results from the mungbean seed bioassay, the EC50, the NOAEC and the LOAEC were not detected, with the exception of one replicate that yielded an NOAEC of 40% and an LOAEC of 100%.