Note:
FOE 5043 is Flufenacet
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8742323&dopt=Abstract
Fundam
Appl Toxicol. 1996 Feb;29(2):251-9.
Evidence
of chemical stimulation of hepatic metabolism by an experimental
acetanilide (FOE 5043) indirectly mediating reductions in
circulating thyroid hormone levels in
the male rat.
Christenson
WR, Becker BD, Wahle BS, Moore KD, Dass PD, Lake SG, Van Goethem
DL, Stuart BP, Sangha GK, Thyssen JH.
Agriculture
Division, Toxicology, Bayer Corporation,
Stilwell, Kansas 66085-9104, USA.
N-(4-Fluorophenyl)-N-(1-methylethyl)-2-[[5-(trifluoromethyl)-1,3,
4-thiadiazol-2-yl]oxy]acetamide (FOE 5043) is a new acetanilide-type
herbicide undergoing regulatory testing. Previous work in
this laboratory suggested that FOE 5043-induced reductions
in serum thyroxine (T4) levels were mediated via an extrathyroidal
site of action. The possibility that the alterations in circulating
T4 levels were due to chemical induction of hepatic thyroid
hormone metabolism was investigated. Treatment with FOE 5043
at a rate of 1000 ppm as a dietary admixture was found to
significantly increase the clearance of [125I]T4 from the
serum, suggesting an enhanced excretion of the hormone. In
the liver, the activity of hepatic uridine glucuronosyl transferase,
a major pathway of thyroid hormone biotransformation in the
rat, increased in a statistically significant
and dose-dependent manner; conversely, hepatic 5'-monodeiodinase
activity trended downward with dose. Bile flow as well as
the hepatic uptake and biliary excretion of [125I]T4 were
increased following exposure to FOE 5043. Thyroidal function,
as measured by the discharge of iodide ion in response to
perchlorate, and pituitary function, as measured by the capacity
of the pituitary to secrete thyrotropin in response to an
exogenous challenge by hypothalamic thyrotropin releasing
hormone, were both unchanged from the controlled response.
These data suggest that the functional status of the thyroid
and pituitary glands has not been altered by treatment with
FOE 5043 and that reductions in circulating
levels of T4 are being mediated indirectly through an increase
in the biotransformation and excretion of thyroid hormone
in the liver.
PMID:
8742323 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7540336&dopt=Abstract
Toxicol
Appl Pharmacol. 1995 Jun;132(2):253-62.
Extrathyroidally
mediated changes in circulating thyroid
hormone concentrations in the male rat following administration
of an experimental oxyacetamide (FOE 5043).
Christenson
WR, Becker BD, Hoang HD, Wahle BS, Moore KD, Dass PD, Lake
SG, Stuart BP, Van Goethem DL, Sangha GK, et al.
Agriculture
Division, Toxicology, Bayer Corporation,
Stilwell, Kansas 66085-9104, USA.
Evidence
of increased hepatic metabolizing capacity coupled with reductions
in serum thyroxine (T4) levels were noted in the rat during
preliminary toxicity studies with FOE 5043, an oxyacetamide
with herbicidal properties. These findings were consistent
with reports in the literature suggesting that declines in
T4 as a result of exposure to various classes of chemicals
may be mediated extrathyroidally, such as through chemical
induction of hepatic thyroid hormone metabolism. To examine
this question with respect to FOE 5043, male rats were surgically
thyroidectomized and provided thyroid hormone replacement
therapy via implanted osmotic minipumps capable of maintaining
a T4/triiodothyronine (T3) serum concentration for approximately
4 weeks at a level comparable to that of euthyroid controls.
Seven days after minipump implantation, thyroidectomized +
T4/T3 (TX + T4/T3) and nonthyroidectomized intact rats (NTX)
were fed diets containing 0, 25, 1000, or 3000 ppm FOE 5043
for up to 3 weeks. Dose-related and equivalent declines in
total and free serum T4 levels in both TX + T4/T3 and NTX
rats were measured at Weeks 1, 2, and 3. Alterations in thyrotropin,
total, free, and reverse serum T3 levels were also noted in
both TX and NTX animals; however, a compound-related trend
was difficult to discern and, when compared to the T4 response,
the changes were markedly less consistent with respect to
both time and dose. Additionally, dose-related increases in
absolute and relative liver weights were measured in both
TX + T4/T3 and NTX animals. As the only source of thyroid
hormone in the TX + T4/T3 animals was that provided by the
pump, these data suggest that FOE 5043-induced
alterations in serum thyroid hormone levels, most notably
T4, are being mediated indirectly, possibly as a result of
increased hepatic metabolism, rather than through a direct
effect on the thyroid gland.
PMID:
7540336 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12108696&dopt=Abstract
Chemosphere.
2002 Jun;47(9):901-6.
Effect
of concentration, moisture and soil type on the dissipation
of flufenacet from soil.
Gupta
S, Gajbhiye VT.
Division
of Agricultural Chemicals, Indian Agricultural Research Institute,
New Delhi.
Effect
of concentration, moisture and soil type on dissipation of
flufenacet from soil has been studied under laboratory condition.
The treated soil samples (1 and 10 microg/g levels) were incubated
at 25+/-1 degrees C. The effect of moisture was studied by
maintaining the treated soil samples (10 microg/g level) at
field capacity and submerged condition. In general, flufenacet
persisted for 60-90 days at lower and beyond 90 days at high
rate. The dissipation of flufenacet from soil followed first
order kinetics with half-life (DT50) values ranging from 10
to 31 days. The dissipation of flufenacet was faster at low
rate than high rate of application. The slow dissipation at
high rate could be attributed to inhibition of microbial activity
at high rate. There was little overall difference in rate
of dissipation in Ranchi and Nagpur soil maintained at field
capacity and submerged condition moisture regimes. In Delhi
soil net dissipation was faster under field capacity moisture
than submerged condition. Soil types greatly influenced the
dissipation of flufenacet. Dissipation was fastest in Delhi
soil (DT50 10.1-22.3 days) followed by Ranchi soil (DT50 10.5-24.1
days) and least in Nagpur soil (DT50 29.2-31.0 days). The
difference in dissipation could be attributed to the magnitude
of adsorption and desorption of flufenacet in these soils.
PMID:
12108696 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11853478&dopt=Abstract
J Agric
Food Chem. 2002 Feb 27;50(5):1045-52.
Analysis
and detection of the herbicides dimethenamid and flufenacet
and their sulfonic and oxanilic acid degradates in natural
water.
Zimmerman
LR, Schneider RJ, Thurman EM.
U.S.
Geological Survey,
4821 Quail Crest Place, Lawrence, KS 66049, USA. zimmerman.lisa@usgs.gov
Dimethenamid
[2-chloro-N-(2,4-dimethyl-3-thienyl)-N-(2-methoxy-1-methylethyl)acetamide]
and flufenacet [N-(4-fluorophenyl)-N-(1-methylethyl)-2-(5-(trifluoromethyl)-1,3,4-thiadiazol-2-yl)oxy]
were isolated by C-18 solid-phase extraction and separated
from their ethanesulfonic acid (ESA) and oxanilic acid (OXA)
degradates during their elution using ethyl acetate for the
parent compound, followed by methanol for the polar degradates.
The parent compounds were detected using gas chromatography-mass
spectrometry in selected-ion mode. The ESA and OXA degradates
were detected using high-performance liquid chromatography--electrospray
mass spectrometry (HPLC-ESPMS) in negative-ion mode. The method
detection limits for a 123-mL sample ranged from 0.01 to 0.07
microg/L. These methods are compatible with existing methods
and thus allow for analysis of 17 commonly used herbicides
and 18 of their degradation compounds with one extraction.
In a study of herbicide transport near the mouth of the Mississippi
River during 1999 and 2000, dimethenamid and its ESA and OXA
degradates were detected in surface water samples during the
annual spring flushes. For flufenacet,
the only detections at the study site were for the ESA degradates
in samples collected at the peak of the herbicide spring flush
in 2000. The low frequency of detections in surface water
likely is due to dimethenamid and flufenacet being relatively
new herbicides. In addition, detectable amounts of
the stable degradates have not been detected in ground water.
PMID:
11853478 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11779079&dopt=Abstract
Bull Environ
Contam Toxicol. 2001 Oct;67(4):609-16.
No
Abstract available
Persistence,
mobility, and adsorption of the herbicide flufenacet in the
soil of winter wheat crops.
Rouchaud
J, Neus O, Eelen H, Bulcke R.
Phytopharmacy
Laboratory, Catholic University of Louvain, Louvain-la-Neuve,
Belgium.
PMID:
11779079 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11464796&dopt=Abstract
Pest Manag
Sci. 2001 Jul;57(7):633-9.
Adsorption-desorption
behaviour of flufenacet in five different soils of India.
Gajbhiye
VT, Gupta S.
Division
of Agricultural Chemicals, Indian Agricultural Research Institute,
New Delhi-110 012, India.
Adsorption-desorption
of the herbicide flufenacet (FOE 5043) has been studied in
five soils from different locations in India (Delhi, Ranchi,
Nagpur, Kerala and Assam) varying in their physicochemical
properties. The organic matter (OM) content varied from 0.072
to 0.864%, clay content from 2.5 to 43.7% and pH from 4.45
to 8.35. The adsorption studies were carried out using a batch
equilibration technique. Ten grams of soil were equilibrated
with 20 ml of aqueous 0.01 M CaCl2 solution containing different
concentrations (0-30 mg litre-1) of flufenacet. After equilibration,
an aliquot of supernatant was taken out for analysis. During
desorption, the amount withdrawn for analysis was replenished
with fresh 0.01 M CaCl2 solution and further equilibrated.
Desorption studies were carried out with the 30 mg litre-1
concentration of flufenacet only. The adsorption studies revealed
that there was moderate to high adsorption of flufenacet considering
the comparatively low organic carbon content in the five test
soils. Average Kd values ranged from 0.77 to 4.52 and Freundlich
KF values from 0.76 to 4.39. The highest adsorption was observed
in Kerala soil (OM 0.786%; clay 25%; pH 4.45) followed by
Ranchi, Nagpur and Delhi soils, and the lowest in Assam soil
(OM 0.553%; clay 2.5%; pH 6.87). The trend in adsorption could
be attributed to the chemical nature of flufenacet and the
physicochemical properties of the soil such as pH, OM and
clay contents. OM and clay contents were positively correlated
whereas pH was negatively correlated. Soils having low pH,
high OM and high clay contents showed higher adsorption. Desorption
studies revealed that there was a hysteresis effect in all
the soils. Hysteresis coefficient values (ratio of n(ad) and
n(des)) varied from 0.09 to 0.45. The
study implies that, because of its moderate to high adsorption,
flufenacet is likely to persist in soil for some time.
However, the possibility of its movement by leaching or surface
run off is less.
PMID:
11464796 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=11080330&dopt=Abstract
Bull Environ
Contam Toxicol. 2001 Jan;66(1):9-16.
No
Abstract available
Adsorption-desorption,
persistence, and leaching behavior of flufenacet in alluvial
soil of India.
Gupta
S, Gajbhiye VT, Agnihotri NP.
Division
of Agricultural Chemicals, Indian Agricultural Research Institute,
New Delhi-110 012, India.
PMID:
11080330 [PubMed - indexed for MEDLINE]
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10501722&dopt=Abstract
Bull Environ
Contam Toxicol. 1999 Oct;63(4):460-6.
No
Abstract available
Flufenacet
soil persistence and mobility in corn and wheat crops.
Rouchaud
J, Neus O, Cools K, Bulcke R.
Phytopharmacy
Laboratory, Catholic University of Louvain, 3, Place Croix
du Sud, SCI, 15D, 1348 Louvain-la-Neuve, Belgium.
PMID:
10501722 [PubMed - indexed for MEDLINE]
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