with this study they demonstrated the need to conduct research on the prevalence of
NSAIDs in all bodies of water, including lakes and dams.
Patrolecco et al. [35] studied surface water samples from the Tiber and Aniene
rivers in Italy using liquid chromatography coupled to tandem mass spectrometry,
finding that diclofenac and ibuprofen were at high concentrations 17 and 20 ng/L,
respectively, while other NSAIDs such as naproxen and ketoprofen were present in
maximum concentrations of 15 and 9 ng/L. In their investigation, they found that
diclofenac and ibuprofen were still the NSAIDs most present in the treated waters
since after the treatment processes, most of the pharmaceutical products were not
completely eliminated. In another investigation, diclofenac and five of its metabolites were identified in different water samples from rivers in Karachi, Pakistan;
finding diclofenac in high concentrations of up to 8.5 μg/L and only in a sample of
water was found in moderate concentrations of 0.1 μg/L. When studying the
metabolites of diclofenac, the authors conclude that hydroxy derivatives appear to
reflect human excretions through domestic wastewater, while the chlorocarbazole
derivative would be related to the abiotic photolytic transformation of
diclofenac [23].
Other studies used different techniques for the detection of NSAIDs. Li et al. [26]
evaluated a new adsorbent for magnetic solid-phase extraction using samples from
Furong Lake in Xiamen, China, finding ibuprofen levels of 0.80 and 0.94 μg/L of
mefenamic acid. In some studies the concentration of NSAIDs in surface waters is
determined by sampling in estuaries. Omar et al. [43] conducted a study of this type
to determine concentrations of diclofenac in the estuary of the Klang river in
Malaysia, which is a section of a river that has been invaded by the sea due to the
influence of tides and the sinking of riversides in which large deposits of sludge
accumulate, so this matrix of sediments is considered a sink for several pollutants.
This study revealed the presence of diclofenac at 13.88 ng/g dry weight. The same
authors in 2019 studied the presence of diclofenac in the same river, applying C18
polymer cartridges as extraction sorbent and measuring LC MS/MS technique,
finding diclofenac levels equal to 10.8 ng/L. Although this evaluation revealed a
negligible risk, its methods and results can be used to monitor changes in the future
and to compare with other tropical aquatic ecosystems [36].
Antonic and Heath [12] selected the four most widely used NSAIDs in Slovenia
and Central Europe (ibuprofen, naproxen, ketoprofen, and diclofenac) to determine
their presence through sediment sample extraction and GC-MS. The analysis was
carried out with two river samples from the vicinity of Novo mesto, the largest city in
the southeastern part of Slovenia. Analysis of sediment samples showed maximum
levels of 0.21, 0.15, 0.25, and 0.10 μg/g for ibuprofen, naproxen, ketoprofen, and
diclofenac, respectively. Duan et al. [44] determined through LC-MS concentrations
of NSAIDs (ng/g dry weight) in sediments of a river that receives wastewater in
Shanghai, China. Ketoprofen, naproxen, and ibuprofen were not detected or were
found within the limits of quantification. The maximum concentration of diclofenac
was determined 1.6 km downstream (12.9 Æ 5.69 ng/g). For their part, Dobor et al.
[7] studied sediment samples collected in the urban area of the Danube River,
between 1,642 and 1,622 km. The determination of the concentration of NSAIDs
Worldwide Occurrence, Detection, and Fate of Nonsteroidal Anti-inflammatory. . .
67
NSAIDs in all bodies of water, including lakes and dams.
Patrolecco et al. [35] studied surface water samples from the Tiber and Aniene
rivers in Italy using liquid chromatography coupled to tandem mass spectrometry,
finding that diclofenac and ibuprofen were at high concentrations 17 and 20 ng/L,
respectively, while other NSAIDs such as naproxen and ketoprofen were present in
maximum concentrations of 15 and 9 ng/L. In their investigation, they found that
diclofenac and ibuprofen were still the NSAIDs most present in the treated waters
since after the treatment processes, most of the pharmaceutical products were not
completely eliminated. In another investigation, diclofenac and five of its metabolites were identified in different water samples from rivers in Karachi, Pakistan;
finding diclofenac in high concentrations of up to 8.5 μg/L and only in a sample of
water was found in moderate concentrations of 0.1 μg/L. When studying the
metabolites of diclofenac, the authors conclude that hydroxy derivatives appear to
reflect human excretions through domestic wastewater, while the chlorocarbazole
derivative would be related to the abiotic photolytic transformation of
diclofenac [23].
Other studies used different techniques for the detection of NSAIDs. Li et al. [26]
evaluated a new adsorbent for magnetic solid-phase extraction using samples from
Furong Lake in Xiamen, China, finding ibuprofen levels of 0.80 and 0.94 μg/L of
mefenamic acid. In some studies the concentration of NSAIDs in surface waters is
determined by sampling in estuaries. Omar et al. [43] conducted a study of this type
to determine concentrations of diclofenac in the estuary of the Klang river in
Malaysia, which is a section of a river that has been invaded by the sea due to the
influence of tides and the sinking of riversides in which large deposits of sludge
accumulate, so this matrix of sediments is considered a sink for several pollutants.
This study revealed the presence of diclofenac at 13.88 ng/g dry weight. The same
authors in 2019 studied the presence of diclofenac in the same river, applying C18
polymer cartridges as extraction sorbent and measuring LC MS/MS technique,
finding diclofenac levels equal to 10.8 ng/L. Although this evaluation revealed a
negligible risk, its methods and results can be used to monitor changes in the future
and to compare with other tropical aquatic ecosystems [36].
Antonic and Heath [12] selected the four most widely used NSAIDs in Slovenia
and Central Europe (ibuprofen, naproxen, ketoprofen, and diclofenac) to determine
their presence through sediment sample extraction and GC-MS. The analysis was
carried out with two river samples from the vicinity of Novo mesto, the largest city in
the southeastern part of Slovenia. Analysis of sediment samples showed maximum
levels of 0.21, 0.15, 0.25, and 0.10 μg/g for ibuprofen, naproxen, ketoprofen, and
diclofenac, respectively. Duan et al. [44] determined through LC-MS concentrations
of NSAIDs (ng/g dry weight) in sediments of a river that receives wastewater in
Shanghai, China. Ketoprofen, naproxen, and ibuprofen were not detected or were
found within the limits of quantification. The maximum concentration of diclofenac
was determined 1.6 km downstream (12.9 Æ 5.69 ng/g). For their part, Dobor et al.
[7] studied sediment samples collected in the urban area of the Danube River,
between 1,642 and 1,622 km. The determination of the concentration of NSAIDs
Worldwide Occurrence, Detection, and Fate of Nonsteroidal Anti-inflammatory. . .
67