INRS-ETE, Université du Québec, 490 rue de la Couronne, Québec, Canada G1K 9A9.
Chemosphere. 2011 Feb;82(6):923-8. doi: 10.1016/j.chemosphere.2010.10.035. Epub 2010 Nov 20.
The presence of bis(2-ethylhexyl) phthalate (DEHP) and its metabolites, i.e. 2-ethylhexanol, 2-ethylhexanal, and 2-ethylhexanoic acid in wastewater sludge (WWS) were investigated during aerobic digestion and Bacillus thuringiensis (Bt)-based fermentation of WWS. Ultrasonication and Fenton oxidation pre-treatment was applied to improve biodegradability of WWS and bioavailability of the target compounds for digestion and fermentation. DEHP and 2-ethylhexanoic acid were observed at higher concentration, meanwhile 2-ethylhexanol and 2-ethylhexanal were observed at lower concentration in WWS. After 20-day aerobic digestion, DEHP removal was 72%, 89%, and 85%, and 2-ethylhexanoic acid removal was 71%, 84%, 79%, respectively for raw, ultrasonicated, and Fenton-oxidized sludges. Bt was found to degrade DEHP, leading to DEHP removal of 21%, 40%, and 30%, respectively for raw, ultrasonicated, and Fenton-oxidized sludges in the fermentation. The results suggested that aerobic stabilization and Bt-based fermentation can remove the phthalates, and pre-treatment of WWS was also effective in improvement of DEHP biodegradation. Hence, Bt-based biopesticide production from WWS can be applied safely when taking into consideration the phthalate contaminants.
研究了在好氧消化和苏云金芽孢杆菌（Bt）发酵过程中，废水中污泥（WWS）中邻苯二甲酸二（2-乙基己基）酯（DEHP）及其代谢物，即 2-乙基己醇、2-乙基己醛和 2-乙基己酸的存在情况。采用超声和芬顿氧化预处理来提高 WWS 的生物降解性和目标化合物的生物可利用性，以促进消化和发酵。在 WWS 中观察到 DEHP 和 2-乙基己酸的浓度较高，而 2-乙基己醇和 2-乙基己醛的浓度较低。经过 20 天的好氧消化，原始、超声和芬顿氧化污泥中 DEHP 的去除率分别为 72%、89%和 85%，2-乙基己酸的去除率分别为 71%、84%和 79%。Bt 被发现可以降解 DEHP，导致原始、超声和芬顿氧化污泥中的 DEHP 去除率分别为 21%、40%和 30%。结果表明，好氧稳定和 Bt 发酵可以去除邻苯二甲酸酯，WWS 的预处理也可以有效提高 DEHP 的生物降解性。因此，在考虑到邻苯二甲酸酯污染物的情况下，可以安全地将 WWS 用于生产 Bt 生物农药。
