TY - JOUR
T1 - Persistence and partitioning of eight selected pharmaceuticals in the aquatic environment
T2 - Laboratory photolysis, biodegradation, and sorption experiments
AU - Yamamoto, Hiroshi
AU - Nakamura, Yudai
AU - Moriguchi, Shigemi
AU - Nakamura, Yuki
AU - Honda, Yuta
AU - Tamura, Ikumi
AU - Hirata, Yoshiko
AU - Hayashi, Akihide
AU - Sekizawa, Jun
PY - 2009/2
Y1 - 2009/2
N2 - We selected eight pharmaceuticals with relatively high potential ecological risk and high consumption-namely, acetaminophen, atenolol, carbamazepine, ibuprofen, ifenprodil, indomethacin, mefenamic acid, and propranolol-and conducted laboratory experiments to examine the persistence and partitioning of these compounds in the aquatic environment. In the results of batch sunlight photolysis experiments, three out of eight pharmaceuticals-propranolol, indomethacin, and ifenprodil-were relatively easily photodegraded (i.e., half-life < 24 h), whereas the other five pharmaceuticals were relatively stable against sunlight. The results of batch biodegradation experiments using river water suggested relatively slow biodegradation (i.e., half-life > 24 h) for all eight pharmaceuticals, but the rate constant was dependent on sampling site and time. Batch sorption experiments were also conducted to determine the sorption coefficients to river sediments and a model soil sample. The determined coefficients (Kd values) were much higher for three amines (atenolol, ifenprodil, and propranolol) than for neutral compounds or carboxylic acids; the Kd values of the amines were comparable to those of a four-ring polycyclic aromatic hydrocarbon (PAH) pyrene. The coefficients were also higher for sediment/soil with higher organic content, and the organic carbon-based sorption coefficient (log Koc) showed a poor linear correlation with the octanol-water distribution coefficient (log Dow) at neutral pH. These results suggest other sorption mechanisms-such as electrochemical affinity, in addition to hydrophobic interaction-play an important role in sorption to sediment/soil at neutral pH.
AB - We selected eight pharmaceuticals with relatively high potential ecological risk and high consumption-namely, acetaminophen, atenolol, carbamazepine, ibuprofen, ifenprodil, indomethacin, mefenamic acid, and propranolol-and conducted laboratory experiments to examine the persistence and partitioning of these compounds in the aquatic environment. In the results of batch sunlight photolysis experiments, three out of eight pharmaceuticals-propranolol, indomethacin, and ifenprodil-were relatively easily photodegraded (i.e., half-life < 24 h), whereas the other five pharmaceuticals were relatively stable against sunlight. The results of batch biodegradation experiments using river water suggested relatively slow biodegradation (i.e., half-life > 24 h) for all eight pharmaceuticals, but the rate constant was dependent on sampling site and time. Batch sorption experiments were also conducted to determine the sorption coefficients to river sediments and a model soil sample. The determined coefficients (Kd values) were much higher for three amines (atenolol, ifenprodil, and propranolol) than for neutral compounds or carboxylic acids; the Kd values of the amines were comparable to those of a four-ring polycyclic aromatic hydrocarbon (PAH) pyrene. The coefficients were also higher for sediment/soil with higher organic content, and the organic carbon-based sorption coefficient (log Koc) showed a poor linear correlation with the octanol-water distribution coefficient (log Dow) at neutral pH. These results suggest other sorption mechanisms-such as electrochemical affinity, in addition to hydrophobic interaction-play an important role in sorption to sediment/soil at neutral pH.
KW - Biodegradation
KW - Pharmaceuticals
KW - Photolysis
KW - Sediment
KW - Sorption
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U2 - 10.1016/j.watres.2008.10.039
DO - 10.1016/j.watres.2008.10.039
M3 - Article
C2 - 19041113
AN - SCOPUS:58549083545
VL - 43
SP - 351
EP - 362
JO - Water Research
JF - Water Research
SN - 0043-1354
IS - 2
ER -