Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas-INIFTA, CCT-La Plata-CONICET, Universidad Nacional de La Plata, Casilla de Correo 16, Sucursal 4, 1900 La Plata, Buenos Aires, Argentina.
Water Res. 2012 Oct 1;46(15):4732-40. doi: 10.1016/j.watres.2012.06.022. Epub 2012 Jun 19.
The photodegradation of a mixture of the emerging pollutants (EPs) clofibric acid, amoxicillin, acetamiprid, acetaminophen, carbamazepine, and caffeine was studied under irradiation with a xenon lamp. The quantum efficiencies of the EPs were determined when irradiated individually. Experiments with the mixture of the EPs showed that indirect photoprocesses attributable to interaction between EPs can either enhance the photodegradation rate by photosensitization or decrease it by quenching processes. The addition of humic substances (HS) to the solutions resulted in an increase of indirect photoprocesses with higher effects on acetaminophen and carbamazepine; this was more remarkable when a filter was used to cut off radiation in the range 280-295 nm. Experiments carried out with chemical probes indicated that the triplet excited states of HS play a major role in the photosensitization process, although the contribution of other species cannot be completely ruled out. Additionally, V. fischeri toxicity tests showed a synergistic effect produced by the mixture of EPs before irradiation. Photodegradation resulted in an enhanced toxicity of the solution at the initial steps of the process, which was associated both with synergistic effects and with the formation of toxic photodegradation by-products of clofibric acid.
研究了在氙灯照射下，新兴污染物（EPs）氯氟苯酸、阿莫西林、乙虫脒、对乙酰氨基酚、卡马西平和咖啡因混合物的光降解情况。单独照射时，测定了 EPs 的量子效率。EPs 混合物的实验表明，归因于 EPs 之间相互作用的间接光过程可以通过光增感作用增强光降解速率，或者通过猝灭过程降低光降解速率。将腐殖质（HS）添加到溶液中会导致间接光过程增加，对乙酰氨基酚和卡马西平的影响更大；当使用过滤器过滤掉 280-295nm 范围内的辐射时，效果更为显著。用化学探针进行的实验表明，HS 的三重激发态在光增感过程中起主要作用，尽管不能完全排除其他物种的贡献。此外，发光细菌毒性试验表明，辐照前 EP 混合物具有协同作用。光降解导致溶液在初始阶段的毒性增强，这与协同作用以及氯氟苯酸有毒光降解副产物的形成有关。
