dc.description.abstract |
Στην παρούσα μεταπτυχιακή εργασία γίνεται διερεύνηση της μεταβολικής τύχης
φαρμακευτικών ουσιών στο υδάτινο περιβάλλον. Πιο συγκεκριμένα,
εξετάζονται 66 φαρμακευτικές ενώσεις (acetaminophen, acetylsalicylic acid,
diclofenac, fenoprofen, ibuprofen, indomethacine, ketoprofen, mefenamic acid,
naproxen, propyphenazone, salicylic acid, amoxicillin, chloremphenicol,
clarithromycin, enrofloxacin, erythromycin, lincomycin, macrolides, monensin
Na, metronidazole, norfloxacin, ofloxacin, penicillin V, roxithromycin,
sulfamethazine, sulfamethoxazole, sulfonamide, tetracycline, trimethoprim,
tylosin, atrovastatin, bezafibrate, clofibric acid, fenofibrate, gemfibrozil,
pravastatin, diltiazem, enalapril, furosemide, hydrochlorothiazide, glibenclamide,
atenolol, metoprolol, propranolol, sotalol, bisphenol A, 17β- estradiol, estriol,
estrone, 17α- ethinylestradiol, 4-nonylphenol, 4-pktylphenol, androstenedione,
testosterone, dihpenhydramin, cimetidine, famotidine, loratidine, ranitidine,
carbamazepine, diazepam, fluoxetine, lorazepam, salbutamol, triclosan,
galaxolide, tonalide, caffeine και oxybenzone) που ανήκουν σε 13 διαφορετικές
θεραπευτικές κατηγορίες, οι οποίες εντοπίστηκαν στη γραμμή επεξεργασίας
των αστικών λυμάτων, καθώς και στη γραμμή επεξεργασίας του πόσιμου νερού.
Τα στοιχεία αφορούν για τις εγκαταστάσεις επεξεργασίας λυμάτων (ΕΕΛ) το
συμβατικό σύστημα της ενεργού ιλύος, το σύστημα MBR, το σύστημα SBR σε
λίγες περιπτώσεις, καθώς και πλήθος περιπτώσεων όπου διαθέτουν έργα
τριτοβάθμιας επεξεργασίας, ενώ στις εγκαταστάσεις επεξεργασίας νερού (ΕΕΝ)
αφορούν στο συμβατικό σύστημα, καθώς και σε προχωρημένες μεθόδους
επεξεργασίας αυτού. Οι κατηγορίες των φαρμακευτικών ενώσεων είναι τα
αναλγητικά/ αντιφλεγμονώδη φάρμακα, τα αντιβιοτικά, τα αντιϊσταμινικά, τα
διουρητικά, ρυθμιστές λιπιδίων του αίματος, αντιδιαβητικά, β-αναστολείς,
ορμόνες, ψυχιατρικά, β-παρεμποδιστές, αντισηπτικά, καλλυντικά, κ.ά..
Ακολούθως τα στοιχεία αυτά αναλύονται και παρατηρούνται τα ποσοστά
απομάκρυνσης, καθώς και το εύρος διακύμανσης για κάθε φαρμακευτική
ένωση. Έτσι πραγματοποιείται σύγκριση και ταξινόμηση της
αποτελεσματικότητας της απομάκρυνσης της κάθε ουσίας, όπου συμπεραίνεται
ότι το σύνολο των φαρμακευτικών ενώσεων, ανεξαρτήτως της κατηγορίας που
ανήκουν, παρουσιάζουν ένα μεγάλο εύρος στα ποσοστά απομάκρυνσης από τις εγκαταστάσεις επεξεργασίας λυμάτων και νερού, τόσο μεταξύ των επιμέρους
εγκαταστάσεων, όσο και μεταξύ των διαφόρων σταδίων/ διεργασιών/
βαθμίδων επεξεργασίας. Η παραπάνω ανάλυση δείχνει επίσης ότι οι υψηλότερες
ποσότητες ουσιών που απορρίπτονται αφορούν στα αντιυπερτασικά, βήτα-
αναστολείς και αναλγητικά / αντιφλεγμονώδη, ενώ ο υψηλότερος κίνδυνος
είναι από τα αντιβιοτικά, τα ψυχιατρικά φάρμακα, όπως και τα αναλγητικά /
αντιφλεγμονώδη. Αυτά τα αποτελέσματα που προκύπτουν μπορούν να
βοηθήσουν επιστήμονες και διοικητικούς υπαλλήλους στο σχεδιασμό μέτρων με
στόχο τη μείωση των επιπτώσεων των επεξεργασμένων αστικών λυμάτων που
απορρίπτονται στα επιφανειακά ύδατα, αλλά και των επιπτώσεων από την
επεξεργασία του πόσιμου νερού που καταναλώνεται από τους ανθρώπους.
Στη συνέχεια πραγματοποιείται μία μελέτη περίπτωσης, όπου λαμβάνονται
δεδομένα από τον όμιλο ΠΡΟΣΥΦΑΠΕ, ως προς την κατανάλωση (μηνιαία και
ετήσια) συγκεκριμένων δραστικών ενώσεων, που είναι η ibuprofen, η naproxen
και η ketoprofen και γίνεται σύγκριση με τις τιμές των συγκεντρώσεων των
ουσιών που έχουν προσδιοριστεί από επί τόπου μετρήσεις (Πανεπιστήμιο
Αθηνών, 2011). Ακόμα, για τις τρεις αυτές ουσίες γίνεται εκτίμηση της
απομάκρυνσης των συγκεντρώσεών τους στα επιμέρους στάδια επεξεργασίας
της εγκατάστασης επεξεργασίας λυμάτων Ψυτάλλεια και εξάγεται το
συμπέρασμα ότι οι συγκεντρώσεις στα ανεπεξέργαστα λύματα της
εγκατάστασης για τις ουσίες αυτές είναι 0,07-3,8 (ανάλογα με το ποσοστό
απέκκρισης από τον ανθρώπινο οργανισμό), 0,21 και 0,08 ppb (μg/L)
αντίστοιχα. Επιπρόσθετα, για κάθε δραστική ένωση γίνεται εκτίμηση της
ποσότητας που εξέρχεται από τα έργα πρωτοβάθμιας και δευτεροβάθμιας
επεξεργασίας της εγκατάστασης, μέσω των βαθμών απομάκρυνσης που έχουν
εξαχθεί κατά την βιβλιογραφική ανασκόπηση για κάθε ένωση και έχουν
προκύπτει σε ένα μέσο όρο αυτών. Συμπερασματικά και ενδεικτικά, οι
ποσότητες (kg/έτος) της ibuprofen, naproxen και ketoprofen εξέρχονται από
την εγκατάσταση με δευτεροβάθμια επεξεργασία (συμβατικό σύστημα ενεργού
ιλύος) είναι 0,2-14,5 (ανάλογα το ποσοστό απέκκρισης), 3,4 και 1,9, αντίστοιχα.
Η παρούσα μεταπτυχιακή εργασία περιλαμβάνει επίσης μία βάση δεδομένων,
μέσω της οποίας μπορεί να γίνει μία προκαταρκτική εκτίμηση του βαθμού
απομάκρυνσης και κατά επέκταση της συγκέντρωσης που θα προκύψει στο τέλος των έργων επεξεργασίας λυμάτων και νερού, ανάλογα με τις
φαρμακευτικές ενώσεις που επιθυμεί ο χρήστης να παρακολουθήσει.
Επισημαίνεται ότι ο βαθμός απομάκρυνσης που έχει καταχωριθεί στη βάση
δεδομένων για κάθε φαρμακευτική ένωση προκύπτει από το μέσο όρο όλων των
βαθμών απομάκρυνσης που έχουν καταγραφεί κατά τη βιβλιογραφική
ανασκόπηση για την κάθε φαρμακευτική ένωση και για την κάθε μέθοδο
επεξεργασίας, σε κάθε στάδιο επεξεργασίας (πρωτοβάθμια, δευτεροβάθμια,
τριτοβάθμια έργα επεξεργασίας) στις εγκαταστάσεις επεξεργασίας λυμάτων και
πόσιμου νερού. |
el |
dc.description.abstract |
In this work is investigated the fate of pharmaceuticals in the aquatic
environment. More specifically, it examined 66 pharmaceutical compounds
(acetaminophen, acetylsalicylic acid, diclofenac, fenoprofen, ibuprofen,
indomethacine, ketoprofen, mefenamic acid, naproxen, propyphenazone,
salicylic acid, amoxicillin, chloremphenicol, clarithromycin, enrofloxacin,
erythromycin, lincomycin, macrolides, monensin Na, metronidazole, norfloxacin,
ofloxacin, penicillin V, roxithromycin, sulfamethazine, sulfamethoxazole,
sulfonamide, tetracycline, trimethoprim, tylosin, atrovastatin, bezafibrate,
clofibric acid, fenofibrate, gemfibrozil, pravastatin, diltiazem, enalapril,
furosemide, hydrochlorothiazide, glibenclamide, atenolol, metoprolol,
propranolol, sotalol, bisphenol A, 17b-estradiol, estriol, estrone, 17thethinylestradiol,
4-nonylphenol, 4-pktylphenol, androstenedione, testosterone,
dihpenhydramin, cimetidine, famotidine, loratidine, ranitidine, carbamazepine,
diazepam, fluoxetine, lorazepam, salbutamol , triclosan, galaxolide, tonalide,
caffeine and oxybenzone) belonging to a large number of classes of drugs such as
analgesics / anti-inflammatory drugs, antibiotics, antihistamines, diuretics, blood
lipid regulators, anti-diabetes, beta-blockers, hormones, psychiatric, betaagonists,
antiseptics, cosmetics, etc.. The total number of pharmaceutical
compounds, regardless of the category they belong, have a wide range in rates of
their removal from sewage treatment plants and water treatment plants, both
among individual plants as also the various processing stages.
Then, this work place a case study, where consuming data (monthly and
annually) is received from the group PROSYFAPE, of specific active compounds,
which are ibuprofen, naproxen and ketoprofen. For the above substances is
simulated the removal of their concentrations in various stages of processing of
sewage treatment plant and concludes that the concentrations at the influent to
the facility for these substances are 7.6, 4.2 and 0,9 ppb (mg/L) respectively.
Additionally, for each active compound is estimated the quantity that enters
(from excretion rate) and leave the WWTP, using the removal rates that is
extracted in the literature review for each compound and are resulting in an
average value of these. In conclusion, the quantities (kg/year) of ibuprofen, naproxen and ketoprofen entering and exiting the facility with secondary
treatment (conventional system of activated sludge) is 127.9-241.7 to 7.6-14.5,
13.8 to 3.4 and 5.8 to 1.9, respectively for the compounds, while the outputs of
tertiary treatment is 0.07-0.1, <0.3 and <0.5, respectively, for most of the
techniques / processes of tertiary treatment.
Finally, this work contains a database through to make the first assessment of
the removal rate which will occur at the end of the sewage treatment works and
water, depending on the works that the user wishes to know. It is noted that the
removal rate which is registered in the database for each pharmaceutical
compound resulting from the average of all grades removal recorded in the
literature review for each pharmaceutical compound and for each processing
method in each stage (primary, secondary, tertiary treatment projects) in
sewage treatment plants and drinking water treatment plants.
Introduction
The pharmaceutical compounds (Pharmaceutical and Personal Care Products,
PPCPs) are synthetic or natural chemicals and they are a class of emerging
environmental contaminants that are extensively and increasingly being used in
human and veterinary medicine. All pharmaceutical compounds containing C
(carbon) and H (hydrogen). The majority of these contain N (nitrogen) and / or O
(oxygen).
People and animals that received by any treatment, specific pharmaceutical
compounds, are the main source of pollution of water resources, which if divided
into different paths depending on whether patients are in private rooms in
homes, hospitals or other places (eg schools, boarding schools) define
qualitative, quantitative, spatial and temporal variability and loads of these
compounds which are charged to the aquatic environment. Presence of pharmaceutical compounds in aquatic environment
The global average annual per capita consumption of pharmaceutical compounds
is at 15 g, while the consumption in developed countries is three to ten times
higher (50-150 g) (Zhang et al., 2008).
Due to the high consumption of pharmaceutical compounds, there is great
potential these have been deposited in the environment in significant quantities.
For instance, in 1983 it has revealed the presence of various antibiotics
(erythromycin, tetracycline and sulfamethoxazole) in water samples from rivers
(Watts et al., 1983). More recent studies in the 1990's in Germany, it has
demonstrated the existence of clofibric acid at concentrations above 165 ng/L in
rivers and groundwater (Stan and Linkerhager, 1994). According to Ternes
(1998) it has revealed the presence of more than 20 drugs in small rivers in
Germany at concentrations above 6 mg/L, while in larger rivers like the Rhine at
lower values which ranged between 0,05 to 0,3 mg/L. Also, Holm et al. (1995)
have reported the presence in groundwater of organic compounds from
pharmaceutical waste. These compounds include sulfonamides,
propylphenazone and barbituric acid, compounds which used by people at
decades from 1940 to 1970 as a kind of treatment. Numerous researchers
(Alexandra Titz and Petra Doll (2009), Ternes (2000) and S. Mompelat et al.
(2009)) argue that the pharmaceutical compounds, leading in surface water or
groundwater from any use and from there to pumping performed for drinking
water.
The majority of studies from the literature indicate the general presence of
pharmaceutical compounds in water bodies at concentrations of ng/L to several
mg/L, and more rare, but essential for human health, drinking water, indicating
the main therapeutic categories, nonsteroidal anti-inflammatory drugs and
antibiotics.
Given the fate of pharmaceutical compounds, their concentration decreases from
wastewater on the environment. For example, ofloxacin, a fluoroquinolone
antibiotic, was detected in the effluent of hospitals at 35,5 mg/L in Albuquerque
(New Mexico, USA), while the influent and effluent of STP was determined at a
concentration 410 ng/L and 110 ng/L, respectively, representing no more than 77% of the rate of removal of the WWTP, and subsequently has not been detected in surface waters notably the Rio Grande River (Brown et al., 2006
Nonsteroidal anti-inflammatory drugs (NSAIDs) have the highest concentrations
were recorded, ranging between 0,4 ng/L to 15 mg/L. Some of them are
diclofenac, paracetamol and ibuprofen (Jux et al., 2002, Moder et al., 2007). Other
major compounds is caffeine, with a maximum concentration of 6 mg/L, the
antibiotic sulfamethoxazole with 1,9 mg/L in the U.S. (Kolpin et al., 2002), the
antiepileptic carbamazepine to 1,3 mg/L in Germany (Zühlke et al., 2004) and
Canada (Hua et al., 2006), the lipid regulator gemfibrozil up to 790 ng/L (Kolpin
et al., 2002 ), anti-oxic ranitidine up to 580 ng/L (Kolpin et al., 2002), a betablocker
atenolol with 241 ng/L in Italy (Zuccato et al., 2005) or less in the United
Kingdom (Kasprzyk-Hordern et al., 2007) and antidiabetic metformin up to 150
ng/L (Kolpin et al., 2002). Other substances such as paracetamol was detected in
211 ng/L in French wells (Rabiet et al., 2006), carbamazepine (up to 465 ng/L
between 5 and 10 m below the ground, Heberer et al. (2004)) and clofibric acid
in Germany at 125 ng/L (Heberer et al., 2004). The presence of ibuprofen,
salicylic acid, gemfibrozil, naproxen, indomethacine and bezafibrate was found in
effluent from septic tanks located in Ontario, Canada at concentrations up to
2150, 480, 430, 300, 4 and 12 ng/L, respectively, some of which are still found up
to 10 to 20 m downstream of the land until a few micrograms / L (Carrara et al.,
2008).
Metabolites of these compounds are often detected at entrances and in
wastewater treatment plants, but not systematically in natural waters. Among
the different pollution profiles, carbamazepine is of great interest as it can be
used as a tracer in order to emphasize the anthropogenic contribution in the
transport and distribution of substances, and hence the metabolic fate in
groundwater (Reinstorf et al., 2008, Osenbrück et al., 2007). One study gathered
the five products of carbamazepine (10,11-dihydro-10 ,11-epoxycarbamazepine,
10,11-dihydro-10, 11 - dihydroxy-carbamazepine, 2 hydroxycarbamazepine, 3-
hydroxycarbamazepine and 10.11-dihydro-10 - hydroxycarbamazepine), in a
treatment plant in Peterborough, Canada, and has identified relevant
concentrations of 426, 52, 1325, 132 and 9 ng/L respectively, while
carbamazepine and 10.11-dihydro-10,11-dihydroxycarbamazepine was detected only at 0,7 and 2,2 ng/L, respectively (Miao and Metcalfe, 2003). It should be noted that these results are in agreement with the very low rate of excretion of
carbamazepine. Despite the low rate of excretion, however, several studies, show
high concentrations in the order of mg/L (Zühlke et al., 2004). Therefore, the
resistance of degradation of carbamazepine, may be the result of the inability of
microorganisms (Pérez and Barceló, 2007) or transport of metabolites into the
environment bound form, and therefore hardly degradable and assimilate them
microorganisms (Lai et al., 2002).
Fate of pharmaceutical compounds in the environment
Regardless of the course to enter the environment, the concentration of a
pharmaceutical substance and its resistance to aqueous systems is determined
by various physicochemical processes. The fate of these can be divided into three
categories:
• transport / dispersion / dilution,
• the sortion and
• degradation.
The transport is the category in which the concentration of pharmaceutical
substances affected by dilution at the point of entry. The extra dispersion and
dilution of the influent water (eg rivers) and turbulent mixing can further reduce
the concentration of these substances. The next category is the sorption of
pharmaceutical substances in the aquatic environment itself. These processes
are performed by bioconcentration, adsorption and deposition in particles. On
the other hand chemicals can return in the aquatic environment through the
degradation of aquatic life, erosion of sediments, and recovering from the
atmosphere during the deposition of particles or gas exchange. The procedures
by which it is possible to reduce the concentration of chemical substances
include photolysis, biodegradation and hydrolysis.
Investigations on the fate of pharmaceutical substances have begun by the mid of
80's. The expected paths of pharmaceutical compounds in the environment
shown in Figure 1, depending on their type. These substances are used for two
main reasons:
a) for human treatment (F1) or
b) veterinary medicinal products (F2).
Veterinary substances also subdivided into those which act as accelerators of
development, therapeutic substances or coccidiostats in domestic production
units (F3) as therapeutic substances in production facilities in the countryside
(F4) and lastly, as food additives in fish farms (F5) . On the other hand, drugs
used for humans, resulting through urine and stool (F6) the sewer system and
from there to biological wastewater treatment plants (F7). Also an unknown
percentage of the pharmaceuticals leads to the sewer system as surplus (Zimmer
et al., 1992) (F8).
The fate of pharmaceutical compounds in the path of aquatic environment can be
divided into three main cases:
a) the substance to undergo full conversion to CO2 and water
b) if the structure is lipophilic and difficult biodegradable this implies that it
remains in the sludge (F9)
c) the substance can be metabolized to a more hydrophilic form but remain
resilient and passes through the treatment of waste water (F10) and result in the
aquatic environment (F11), possibly impacting on aquatic organisms
For the same reasons, medicinal substances used in farming lead to soil either
directly through urine and stool (F12), or indirectly through the deposition of
manure for domestic plants (F13). The drugs used in fish farms are exposed
directly to aquatic environment because their use in fish is by providing them as
supplements to their diet. However, any quantity of food is not eaten by fish, it is
deposited and accumulated on the seabed (Jacobsen and Berglind, 1998).
Removal of pharmaceuticals compounds
In terms of levels / stages of processing in a WWTP, pharmaceutical compounds
are not uncommon organic chemicals and removal rates are reasonably
predictable based on physical and chemical properties of these compounds.
The biological treatment system, in a conversional treatment plant, such as
activated sludge and bio membrane reactor (MBR), shown several times
removing significant amounts of pharmaceutical compounds that are
biodegradable or can readily be associated with microorganisms (Ternes et al.,
1999, Joss et al., 2005, Kim et al., 2007). However, the removal rates for
pharmaceutical compounds can vary within and between studies (Kasprzyk-
Hordern, Dinsdale and Guwy, 2009, Wick et al., 2009), depending on various
factors such as age of the sludge, the temperature of water sludge tank, the
hydraulic residence time, etc.. For example, the removal of diclofenac from an
activated sludge system ranges from 21% to 50%, but this can be optimized by
the process that the facility operates a sludge age of eight days or more (Ziylan &
Ince, 2011). Advanced processing of liquid waste, such as membranes, advanced
oxidation processes (tertiary treatment), etc, have shown high efficiency removal
of pharmaceutical compounds (e.g. advanced oxidation processes can achieve up
to 100% removal of diclofenac, Klavarioti, Mantzavinos & Kassinos, 2009).
However, the conventional method of treatment is usually sufficient to meet
regulatory requirements, and capital-intensive advanced treatments are not
always acceptable for wastewater treatment (Spellman, 2010).
Conventional methods of treatment with flocculation, filtration and chlorination
can remove approximately 50% of these compounds, while the advanced
treatment methods such as ozonation, advanced oxidation, charcoal and membrane processes (e.g. reverse osmosis, nanofiltration ), can achieve higher
rates of removal. Reverse osmosis, for example, can remove over 99% of large
pharmaceutical molecules (WHO, 2011).
Removal in a water treatment facility
For conventional treatment of drinking water, bench-scale studies have shown
that the flocculation (with or without softening by the addition of chemicals) are
largely ineffective for the removal of pharmaceutical compounds (Westerhoff et
al., 2005, Yoon et al., 2006 , Snyder et al., 2007). The free chlorine was found to
oxidize about half of pharmaceutical compounds and chloramines are less
effective. In contrast, antibiotics such as sulfamethoxazole, trimethoprim and
erythromycin are one of the compounds showed high removal of free chlorine
(Khiari, 2007). Advanced water treatment processes (tertiary treatment) such as
ozonation, advanced oxidation, charcoal and membrane processes
(nanofiltration, reverse osmosis), were shown to achieve higher removal rates
(over 99%) for specific pharmaceutical compounds in various published studies.
However, advanced oxidation processes may lead to secondary degradation
products, such as metabolites, and for this reason, future research could examine
the value and feasibility of the formation and the effect of these metabolites
(Celiz, Tso & Aga, 2009 ).
Conclusions and further work
Pharmaceutical compounds are used in large quantities in humans and in
veterinary medicine, thus reaching the aquatic environment mainly through
sewage treatment systems, where concentrations may be found in the levels of
milligrams liter (mg/L). Although we can make some predictions based on
physical and chemical properties, for the fate of pharmaceutical compounds in
the aquatic environment, these generally characterized by different metabolic
fate and behavior, so that the efficiency of their removal during wastewater
treatment are not clear. Pharmaceutical compounds are usually present in the influent wastewater at
concentrations of about 100mg/L and even more, so the majority of STPs is
unable to effectively remove all of these compounds. The published literature
and individual studies have shown that concentrations of pharmaceutical
compounds in surface and ground waters affected by discharges and are
typically less than 0,1mg/L (or 100ng/L), and concentrations in treated drinking
water is usually below 0,05mg/L (or 50ng/L). Additionally, it was observed that
the efficiency of removal of pharmaceutical compounds vary in a wide range of
different compounds, and for the same substance, the removal depend on
physical and chemical properties of pharmaceutical compounds and operating
conditions (mainly aerobic, anaerobic, anoxic conditions, the residence time of
solids, pH and temperature), as discussed throughout the study. The operated
MBR system showed ensure higher returns removal for most compounds which
results in a better quality of effluent water from the WWTP.
This paper also shows the fact that the occurrence of certain pharmaceutical
compounds in wastewater after secondary treatment, it works discharged to
surface waters a medium to high risk to aquatic life. In addition, many other
pharmaceutical compounds, even if their concentration was found to be low, the
daily discharge at high loads, could contribute to the adverse effects on aquatic
organisms in the long run because of chronic toxicity.
It is prudent to note that advanced and expensive water treatment technologies
will not be able to completely remove all of these compounds. Therefore, it is
imperative to examine the toxicological significance of these various compounds
in the appreciable risks to human health. Increased or rapidly changing exposure
resulting from the specific local conditions such as increasing the concentration
of pharmaceutical compounds in surface waters from unregulated disposal of
sewage should also be investigated. For these reasons, it would be wiser to start
a program to monitoring the concentrations of the most commonly occurring
medicinal compounds, and those with the highest environmental risk, such as
antibiotics (including erythromycin, ofloxacin, sulfamethoxazole, clarithromycin,
amoxicillin , tetracycline and azithromycin), psychiatric medicines (such as
fluoxetine, diazepam and carbamazepine), analgesics / anti-inflammatories (ibuprofen, mefenamic acid, naproxen, diclofenac and ketoprofen) and
regulators of lipid (fainofivriko acid, fenofibrate and gemfibrozil).
On the part of the legislation is very important to note that the instructions
concerning the protection of the aquatic environment and related agencies are
Framework Directive 2000/60/EC (WFD), Directive 2006/118/EC (GWD) to
protect groundwater and Directive 2008/105/EC (PSD), stating the list of
priority substances (also known as Annex X of WFD) for surface waters and
related Environmental Quality Standards (EQS).
Despite the fact that the increasing research activities in wastewater and water
treatment, there is still a great need for future research and further investigation
to assess the importance of the residues of pharmaceutical compounds in terms
of endurance / resistance, and potential environmental impacts that may result.
The development of indicators for the contamination of sewage and surface
water by pharmaceutical compounds would also be useful in this direction, as
well as the parallel registration of bibliographic and experimental data and data
on hazards, biodegradability and metabolic fate of pharmaceutical compounds,
regardless of their use. The specific criteria relating to the toxicity and
biodegradation can be defined for the compounds tend to enter the WWTP and
DWTP, and restrictions could be imposed even on the production and use of
compounds, if these criteria are not met.
Any changes in the parameters of the wastewater and water should be taken into
account, as well as the financial cost. Similarly, restrictions or uses of drugs
should be weighed against the possible loss / benefit human health and / or the
environment resulting from the administration of these drugs. |
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