• Highly removed compounds (>70%): acetaminophen, alfuzosin, alprazolam,
atenolol, atorvastatin, azithromycin, caffeine, codeine, dipyridamole, famotidine,
fenofibrate, furosemide, ibuprofen, levomepromazine, metronidazole, metoprolol, mianserin, nadolol, naproxen, nifuroxazide, ofloxacin, paroxetine, ranitidine,
salbutamol, salicylic acid, sulfadimethoxine, sulfapyridine and verapamil
• Moderately removed (40–70%): bezafibrate, clarithromycin, clofibric acid, diltiazem, diclofenac, doxycycline, gemfibrozil, ketoprofen, sulfadiazine,
sulfamethazine, sulfamethoxazole, tramadol, trimethoprim and venlafaxine
• Poorly removed (<40%): carbamazepine, cimetidine, clenbuterol, clindamycin,
fexofenadine, glibenclamide, glimepiride, irbesartan, lorazepam, maprotiline,
mefenamic acid, memantine, mirtazapine, oxazepam, perphenazine, phenobarbital and sotalol
CWs are promising to effectively remove (>70%) the pharmaceutical compounds
included in the EU watch list by the Commission Decision 2015/495/EU, diclofenac
and the macrolide antibiotics (erythromycin, clarithromycin and azithromycin),
17-beta-estradiol and oestrone (respectively E2 and E1) and the synthetic hormone
17-alpha-ethinylestradiol (EE2) [55]. However, except for diclofenac that has been
extensively studied, all other compounds were only reported in less than ten or even
five publications [55].
Additionally, making use of the data compiled from Ilyas and van Hullebusch
[28] and adding results from classical activated sludge (CAS) systems (Table 2), it is
possible to establish gross comparisons of removal efficiency between CWs and
conventional WWTPs. As it has been reported in the first studies, CWs can provide
similar (acetaminophen, caffeine, clarithromycin, clofibric acid, diltiazem, doxycycline, fexofenadine, gemfibrozil, ibuprofen, ketoprofen, naproxen, ranitidine,
salicylic acid, sotalol, sulfamethoxazole) or even better removal (atenolol, carbamazepine, codeine, diclofenac, metoprolol, sulfapyridine, tramadol, trimethoprim
and venlafaxine) than conventional technology for domestic and urban wastewater
treatment. Only bezafibrate, sulfadiazine and sulfamethazine are better removed by
CAS than CW, probably the cases were sorption plays a major role as removal
mechanisms.
Regarding transformation products, it is known from other technologies, including other biological processes, that pharmaceuticals removal are rarely mineralized,
but rather a high variety of transformation products are formed [65]. In CWs, studies
reporting transformation products are scarce when compared with the overall data on
parent compounds. Not more than three papers report on the same transformation
product, while several of the transformation products in CWs are only reported once
[28]. Overall, results point the formation of some (e.g. 4-hydroxydiclofenac), while
others (e.g. 1-hydroxyibuprofen or carboxyibuprofen) are removed. There is a clear
knowledge gap on dynamics (formation/removed) of pharmaceutical transformation
products in CWs.
Moreover, Ilyas and van Hullebusch [28] compared for the first time the performance of different aerated systems. Aeration, as an operational option to increase the
efficiency of aerobic processes in CWs (higher BOD removal or nitrification) can
394
P. N. Carvalho
atenolol, atorvastatin, azithromycin, caffeine, codeine, dipyridamole, famotidine,
fenofibrate, furosemide, ibuprofen, levomepromazine, metronidazole, metoprolol, mianserin, nadolol, naproxen, nifuroxazide, ofloxacin, paroxetine, ranitidine,
salbutamol, salicylic acid, sulfadimethoxine, sulfapyridine and verapamil
• Moderately removed (40–70%): bezafibrate, clarithromycin, clofibric acid, diltiazem, diclofenac, doxycycline, gemfibrozil, ketoprofen, sulfadiazine,
sulfamethazine, sulfamethoxazole, tramadol, trimethoprim and venlafaxine
• Poorly removed (<40%): carbamazepine, cimetidine, clenbuterol, clindamycin,
fexofenadine, glibenclamide, glimepiride, irbesartan, lorazepam, maprotiline,
mefenamic acid, memantine, mirtazapine, oxazepam, perphenazine, phenobarbital and sotalol
CWs are promising to effectively remove (>70%) the pharmaceutical compounds
included in the EU watch list by the Commission Decision 2015/495/EU, diclofenac
and the macrolide antibiotics (erythromycin, clarithromycin and azithromycin),
17-beta-estradiol and oestrone (respectively E2 and E1) and the synthetic hormone
17-alpha-ethinylestradiol (EE2) [55]. However, except for diclofenac that has been
extensively studied, all other compounds were only reported in less than ten or even
five publications [55].
Additionally, making use of the data compiled from Ilyas and van Hullebusch
[28] and adding results from classical activated sludge (CAS) systems (Table 2), it is
possible to establish gross comparisons of removal efficiency between CWs and
conventional WWTPs. As it has been reported in the first studies, CWs can provide
similar (acetaminophen, caffeine, clarithromycin, clofibric acid, diltiazem, doxycycline, fexofenadine, gemfibrozil, ibuprofen, ketoprofen, naproxen, ranitidine,
salicylic acid, sotalol, sulfamethoxazole) or even better removal (atenolol, carbamazepine, codeine, diclofenac, metoprolol, sulfapyridine, tramadol, trimethoprim
and venlafaxine) than conventional technology for domestic and urban wastewater
treatment. Only bezafibrate, sulfadiazine and sulfamethazine are better removed by
CAS than CW, probably the cases were sorption plays a major role as removal
mechanisms.
Regarding transformation products, it is known from other technologies, including other biological processes, that pharmaceuticals removal are rarely mineralized,
but rather a high variety of transformation products are formed [65]. In CWs, studies
reporting transformation products are scarce when compared with the overall data on
parent compounds. Not more than three papers report on the same transformation
product, while several of the transformation products in CWs are only reported once
[28]. Overall, results point the formation of some (e.g. 4-hydroxydiclofenac), while
others (e.g. 1-hydroxyibuprofen or carboxyibuprofen) are removed. There is a clear
knowledge gap on dynamics (formation/removed) of pharmaceutical transformation
products in CWs.
Moreover, Ilyas and van Hullebusch [28] compared for the first time the performance of different aerated systems. Aeration, as an operational option to increase the
efficiency of aerobic processes in CWs (higher BOD removal or nitrification) can
394
P. N. Carvalho