Occurrence of Pharmaceuticals and Personal Care Products in Wastewater Systems

Transcription

1 ccurrence of Pharmaceuticals and Personal Care Products in Wastewater Systems Yutaka SUZUKI *, Koya KMRI, Arata ARADA, Norihide NAKADA, Makoto YASJIMA Water Quality Research Team, Water Environment Research Group, Public Works Research Institute 1. Introduction Recently, there has been a growing public concern about the emergence of environmental pollution of water sources from pharmaceuticals and personal care products (PPCPs). Considering the route PPCPs take to reach water environment, wastewater treatment plants (WWTPs) may facilitate their initial entry. If PPCPs are not properly treated during the wastewater treatment process, they can contaminate water environment, including drinking water sources. Considering the current level of knowledge regarding this problem, it is necessary to clarify the fates of PPCPs in WWTPs to identify appropriate treatment methods. In our research, we analyzed the presence of PPCPs in several WWTPs to clarify the concentrations and fates of PPCPs along the units of wastewater treatment. In addition, toxic effects of antibiotics on aquatic organisms were evaluated with ecotoxicity tests, and ecological risk of the antibiotics was evaluated by comparison between concentrations in water environment and ecotoxicity results. 2. Survey Sites and Methods Surveys were conducted in four or six WWTPs employing conventional activated sludge process, depending on the type of the PPCPs. Twenty four-hour water flow proportional composite samples were collected from several sampling locations in each WWTP. The target PPCPs were four anti-inflammatories (aspirin, ketoprofen, ibuprofen, naproxen), a phenolic antiseptic (triclosan), three amide pharmaceuticals (crotamiton, diethyltoluamide, carbamazepine) and two antibiotics (levofloxacin, clarithromycin). They were analyzed with GC/MS or LS/MS/MS after sample extraction and purification according to the methods by Nakada,N. et al.(26) and Yasojima, M. et al.(26). Ecotoxicity was evaluated with the tests using bacterium, alga and crustacean. * 1-6 Minamihara, Tsukuba, Ibaraki, Japan ysuzuki@pwri.go.jp

2 3. ccurrence and Fate of PPCPs The PPCP concentrations in the influent were of the order of hundreds ng/l, except for carbamazepine of the order of tens ng/l. Almost all of the PPCPs existed in the dissolved form except for triclosan and antibiotics, which might be the reason for no remarkable decrease after the primary sedimentation. During the biological treatment, two anti-inflammatories (aspirin and ibuprofen) and triclosan were effectively removed, while the remaining anti-inflammatories (ketoprofen and naproxen), diethyltoluamide and antibiotics showed around 5% reduction, and crotamiton and carbamazepine was hardly removed. The fates of PPCPs were evaluated by calculating the mass balance of PPCPs in the WWTPs. Ibuprofen was significantly removed and degraded by the activated sludge in the aeration (Figure 1), while triclosan was removed by the adsorption to the activated sludge and the accumulation in the sludge was observed (Figure 2). Antibiotics was removed mainly by the adsorption to the activated sludge, and accumulation in the sludge was observed..9 g/day Return flow N.D N.D. N.D. A B C D <.2 g/day 36 g/day Return flow A B C D 2.6 g/day Drained sludge N.D. Return sludge N.D. Drained sludge 5.3 Return sludge 33 Figure 1 Mass balance of ibuprofen in WWTP Figure 2 Mass balance of triclosan in WWTP 4. Ecotoxicity of Antibiotics Microtox test using marine fluorescent bacterium and Daphnia immobilization test showed that levofloxacin (LVFX) and clarithromycin (CAM) have no acute toxicity on bacterium. Meanwhile, algal growth inhibition test revealed that LVFX and CAM have a toxicity to microalga, but the phytotoxicity of CAM was about 1 fold higher than that of LVFX. Comparison of the concentration in aquatic environment and PNEC indicates that CAM discharged into aquatic environment may affect algae if dilution rate is low. Reference Nakada,N. et al.(26) Pharmaceutical chemicals and endocrine disrupters in municipal wastewater in Tokyo and their removal during activated sludge treatment, Water Research 4, Yasojima, M. et al.(26) ccurrence of levofloxacin, clarithromysin and azithromycin in wastewater treatment plant in Japan, Wat. Sci. & Tech., 53(11),

3 ccurrence of Pharmaceuticals and Personal Care Products in Wastewater Systems Yutaka SUZUKI*, Koya KMRI*, Arata ARADA*, Norihide NAKADA* and Makoto YASJIMA** *Water Quality Research Team Water Environment Research Group Public Works Research Institute **Towa Kagaku Corporation Public Works Research Institute 1. Introduction - Growing public concern about the environment pollution of pharmaceuticals and personal care products (PPCPs) -From existing research, wastewater treatment plants (WWTPs) may facilitate the initial entry of PPCPs to water environment -It is important to clarify the occurrence and fates of PPCPs in WWTPs to evaluate both the effect of treated wastewater on water environment and the performance of WWTPs to remove PPCPs 1

4 -In our research, we conducted surveys in several WWTPs to clarify the concentrations and fates of PPCPs along the units of wastewater treatment. -In addition, toxic effects of PPCPs on aquatic organisms were evaluated with ecotoxicity tests. 2. ccurrence and Fate of PPCPs (Anti-inflammatory Drugs, etc.) in WWTPs Influent Primary effluent Secondary Effluent Final Effluent Primary Sedimentation Tank B Aeration Tank Chlorine Disinfection Final Sedimentation Tank Treatment method : Conventional activated sludge process Treatment capacity : 22,5~7, m 3 /d Number of plants surveyed : 4 Sampling : Composite sample taken every 2 hours 2

5 PPCPs grouping by structural characteristics Anti-inflammatory drugs: Aspirin, Ibuprofen, Fenoprofen, Naproxen, Mefenamic Acid, Ketoprofen aving carboxl group (-C) Phenolic antiseptic: Triclosan Group A aving Phenol Amide pharmaceuticals: Crotamiton (relieve itching) Carbamazepine (Antiepileptic) Group B Group C C 3 C 3 3C C 3 C C C Fenoprofen 解熱鎮痛剤 Fenoprofen Ketoprofen 解熱鎮痛剤 Ketoprofen Naproxen 解熱鎮痛剤 Naproxen Group A 3 C C 3 C 3 C C C C 3 C N 3 C Ibuprofen Ibuprofen 解熱鎮痛剤 Aspirin Aspirin 解熱鎮痛剤 Mefenamic acid 解熱鎮痛剤 Mefenamic Acid Group B Group C Cl N 2 3 C N C 3 C 3 N Cl Cl Triclosan 殺菌剤 Triclosan Crotamiton Crotamiton 鎮痒剤 Carbamazepine Carbamazepine 抗てんかん薬 3

6 (ng/l) 1 Dissolved phase concentration change along treatment units (1) Ibuprofen Triclosan 8 Ibprofen 濃度 (ng/l) 最大値最小値平均値 流入水一次処理水二次処理水放流水 Inf PE SE FE (ng/l) 15 1 Tricrosan 濃度 (ng/l) 5 Inf : Influent PE : Primary Effluent SE : Secondary Effluent FE : Final Effluent 最大値最小値平均値 流入水一次処理水二次処理水放流水 Inf PE SE FE (ng/l) Naproxen 濃度 (ng/l) Dissolved phase concentration change along treatment units (2) Naproxen Ketoprofen 最大値最小値平均値 Ketoprofen 濃度 (ng/l) 流入水一次処理水二次処理水放流水流入水一次処理水二次処理水放流水 Inf PE SE FE Inf PE SE FE Inf PE SE FE (ng/l) Inf : Influent PE : Primary Effluent SE : Secondary Effluent FE : Final Effluent 最大値最小値平均値 4

7 Crotamitone 濃度 (ng/l) Dissolved phase concentration change along treatment units (3) Crotamiton Carbamazepine (ng/l) 最大値最小値平均値 (ng/l) 1 Carbamazepine 濃度 (ng/l) 最大値最小値平均値 流入水一次処理水二次処理水放流水流入水一次処理水二次処理水放流水 Inf PE SE FE Inf PE SE FE Inf PE SE FE Inf : Influent PE : Primary Effluent SE : Secondary Effluent FE : Final Effluent Average PPCP removal ratio in WWTPs PPCPs Removal ratio (%) Aspirin Anti-inflammatory 96 Ibuprofen Anti-inflammatory 95 Triclosan Antiseptic 9 Naproxen Anti-inflammatory 55 Ketoprofen Anti-inflammatory 5 Crotamiton relieve itching 2 Carbamazepine Antiepileptic -25 Mefenamic acid Anti-inflammatory -24 5

8 From the survey of 4 WWTPs, -PPCPs (anti-inflammatory drugs, etc) concentraion in dissolved phase in influent ranged from hundreds to one thousand ng/l except for Carbamazepine -PPCPs could be classified into three groups by the removal ratio in WWTPs Mass balance of PPCPs including solid phase concentration a) Ibuprofen.9 g/day Return flow N.D N.D. N.D. A B C D <.2 g/day b) Triclosan 36 g/day Drained sludge N.D. Return sludge N.D. Return flow A C D B Dissolved Suspended 2.6 g/day Drained sludge 5.3 Return sludge 33 6

9 c) Crotamiton 12. g/day Return flow A B C D Drained sludge.2 d) Carbamazepine 1.3 g/day Return sludge 5.9 Return flow A B C D 1.3 g/day 1.3 g/day Drained sludge.2 Return sludge.8 Dissolved Suspended From the mass balance survey in a WWTP, -Almost of all of the PPCPs existed in the dissolved phase, except for Triclosan which mostly existed in solid phase. -Ibuprofen was decomposed in the biological treatment process effectively -Triclosan was removed by the adsorption to the activetaed sludge, and was accumulated in the activated sludge in a high concentration. - Crotamiton and Carbamazepine was hardly changed in the process 7

10 3. ccurrence and Fate of Antibiotics in WWTP Levofloxacin(LVFX LVFX) 3 C N F N Sampling Screen N C 3 Primary effluent C Aeration Clarithromycin (CAM) Sampling points Final sedimentation C 3 N C 3 C 3 C 3 C 3 C 3 3 C 3 C 3 C C 3 C 3 C 3 C 3 Secondary effluent Activated sludge reactors Influent Primary effluent Conventional activated sludge process 1 Concentration change of antibiotics along treatment units Concentration (ng/l) LVFX n=6 median max min Concentration (ng/l) CAM n=6 median max min Influent Primary effluent Aeration Secondary effluent Influent Primary effluent Aeration Secondary effluent Effect of return sludge? or deconjugation? or other factors? 11 8

11 LVFX CAM Primary sedimentation 291 A 314 Mass balance of antibiotics 1.2 Final Aeration sedimentation B C Primary Final sedimentation Aeration sedimentation A C 1.3 B Dissolved Suspended (μg/d) From the survey of antibiotics, -Antibiotics concentration in the influent ranged from hundreds to one thousand ng/l, and the removal ratio in WWTPs was around 5% -LVFX was removed by the adsorption to the activated sludge, and was accumulated in the activated sludge in a high concentration -CAM accumulation in the sludge was small, which might indicate biodegradation by the activated sludge 9

12 4. Effect of PPCPs on Aquatic rganisms Ecotoxicity tests (acute toxicity) applied - Bacterium: Microtox test - Alga: Algal growth inhibition test - Crustacean: Daphnia acute immobilization test Results of Ecotoxicity tests (mg/l) PPCPs Microtox test Algal growth inhibition test Daphnia acute immobilization test EC5 EC5 EC5 5min 15min 96hour 24hour 48hour Aspirin / Triclosan.6.6 /.4.4 Crotamiton 57.6 / Levofloxacin Clarithromycin.11 : No Effect 1

13 Comparison between EC5 and the concentration of wastewater EC5 (a) Influent (b) Final effluent (c) Triclosan (μg/l) (b or c)/a 1/4 1/4 Clarithromycin (μg/l) (b or c)/a 1/18 1/28 From the ecotoxicity tests, - Antiseptic agent (Triclosan) showed toxicity on Bacterium and Crustacean - Antibiotics showed inhibition to Algal growth - The toxic effect concentration was in the order of mg/l except for Clarithromycin - Clarithromycin in treated wastewater might be evaluated to have toxic effect on Alga if NEC is obtained 11

14 Conclusion - The concentration of most PPCPs in influent ranged from hundreds to one thousand ng/l - Several patterns of PPCP removal in the treatment process were observed; a) effectively decomposed by activated sludge b) adsorbed to activated sludge c) hardly changed - Some PPCPs showed ecotoxicity, but the concentration of the order of mg/l - Antibiotic in treated wastewater might be evaluated to have toxic effect on Alga 12