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
N1 - Funding Information:
This work was supported in part by the Japan Ministry of Education, Culture, Sports, Science and Technology (MEXT) through the Grant-in-Aid for Young Scientists (B). The authors thank Dr. Kozuki and his research group at the University of Tokushima for the organic carbon measurements and thank Drs. Kunikane and Kosaka in National Institute of Public Health in Japan for the zeta potential measurement.
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
SN - 0043-1354
VL - 43
SP - 351
EP - 362
JO - Water Research
JF - Water Research
IS - 2
ER -