TY - JOUR
T1 - Fate and effects of enrofloxacin in aquatic systems under different light conditions
AU - Knapp, C.W.
AU - Cardoza, L.A.
AU - Hawes, J.N.
AU - Wellington, E.M.H.
AU - Larive, C.K.
AU - Graham, D.W.
PY - 2005/12
Y1 - 2005/12
N2 - The fate and effects of fluoroquinolone antibacterials (FQ) in the environment is of significance because of apparent increased FQ
resistance in environmental and clinical organisms. Here we
simultaneously assessed the fate and effects of enrofloxacin (enro), an
FQ often used in agriculture, on the chemistry and in situ microbial
communities in receiving waters. We added enro to 25 mu g/L in nine
outdoor mesocosms maintained under three light conditions (in
triplicate): full sunlight typical of the upper epilimnion (100%
full-light exposure, FLE), partial shading typical of the lower
epilimnion (28% FILE), and near-complete shading typical of the
hypolimnion (0.5% FILE). Enro disappearance and ciprofloxacin (cipro)
formation were monitored overtime using LC/MS, and water chemistry and
ambient microbial communities (using denaturing gradient gel
electrophoresis; DGGE) were characterized. Enro half-lives were 0.8,
3.7, and 72 days for the 100%, 28%, and 0.5% FLE treatments,
respectively, creating three distinct FQ exposure scenarios. Although
FQ exposures ranged from similar to 6 mu g/L for 24 h to similar to 21
mu g/L for 30 days, no statistically significant exposure effects were
noted in water quality or microbial communities (as indicated by
whole-community 16S rDNA DGGE analysis and specific amplification of
the QRDR region of gyrase A). Small changes in water chemistry were
noted over time; however, changes could not be specifically attributed
to FQs. In general, enro addition had minimal effect on water column
conditions at the levels and durations used here; however, further
investigation is needed to assess effects in aquatic sediments.
AB - The fate and effects of fluoroquinolone antibacterials (FQ) in the environment is of significance because of apparent increased FQ
resistance in environmental and clinical organisms. Here we
simultaneously assessed the fate and effects of enrofloxacin (enro), an
FQ often used in agriculture, on the chemistry and in situ microbial
communities in receiving waters. We added enro to 25 mu g/L in nine
outdoor mesocosms maintained under three light conditions (in
triplicate): full sunlight typical of the upper epilimnion (100%
full-light exposure, FLE), partial shading typical of the lower
epilimnion (28% FILE), and near-complete shading typical of the
hypolimnion (0.5% FILE). Enro disappearance and ciprofloxacin (cipro)
formation were monitored overtime using LC/MS, and water chemistry and
ambient microbial communities (using denaturing gradient gel
electrophoresis; DGGE) were characterized. Enro half-lives were 0.8,
3.7, and 72 days for the 100%, 28%, and 0.5% FLE treatments,
respectively, creating three distinct FQ exposure scenarios. Although
FQ exposures ranged from similar to 6 mu g/L for 24 h to similar to 21
mu g/L for 30 days, no statistically significant exposure effects were
noted in water quality or microbial communities (as indicated by
whole-community 16S rDNA DGGE analysis and specific amplification of
the QRDR region of gyrase A). Small changes in water chemistry were
noted over time; however, changes could not be specifically attributed
to FQs. In general, enro addition had minimal effect on water column
conditions at the levels and durations used here; however, further
investigation is needed to assess effects in aquatic sediments.
KW - fate
KW - effects
KW - enrofloxacin
KW - aquatic systems
KW - light conditions
KW - microbiology
KW - chemistry
UR - http://pubs.acs.org/doi/abs/10.1021/es050895l?prevSearch=%2528Fate%2Band%2Beffects%2Bof%2Benrofloxacin%2Bin%2Baquatic%2Bsystems%2Bunder%2Bdifferent%2Blight%2Bconditions%2529%2BAND%2B%255Bauthor%253A%2BCardoza%252C%2BL.%2BA.%255D&searchHistoryKey=
U2 - 10.1021/es050895l
DO - 10.1021/es050895l
M3 - Article
VL - 39
SP - 9140
EP - 9146
JO - Environmental Science and Technology
JF - Environmental Science and Technology
SN - 0013-936X
IS - 23
ER -