Herbicides 1 Flashcards
example of a phenoxy?
2,4-D, MCPA
example of a triazine?
atrazine
example of an amide?
diphenamid
example of a phenyl urea
monuron
example of a carbamate
chloropham
example of a thiocarbamate
triallate
example of a dinitroanaline
benefin
example of a dipyridyl
paraquat
example of a phthalamic acid
dinseb
example of a benzoic acid
dicamba
example of a chloro aliphatic
mecoprop
example of a glyphosphate
roundup
example of a picolinic acid
picrolam (tordon)
what is the post harvest interval?
how long it takes for residues to disappear on the crop so that cows can go back to eating it; may taste the residues in milk, they may be carcinogenic
what are the clinical manifestations of the typical herbicide?
depression, anorexia, diarrhea, ataxia, muscle spasms
what are the postmortem manifestations of a typical herbicide?
lung congestion, liver congestion, milk hemorrhage, increased redness in organs; few residues in tissues
the typical herbicide has a low environmental impact
ya
mechanism of action of phenoxy herbicides?
- uncouples oxphos–>released E–>increases heat–>fever
- reduced ribonuclease synthesis
- muscle damage
- targets gibberellic acid–>hormone found only in plants and fungi
broad spectrum
what are the forms of 2,4 D, and some properties?
acid, water insoluble; ester, water insoluble, volatile; amine, water soluble, not volatile;
kinetics of phenoxy herbicides?
well absorbed; easily metabolized through hydrolysis–>rapid elimination; excreted unchanged in the urine (good for measuring exposure); half life~ 18 h; amine form must be ingested as it is water insol
clinical manifestations of phenoxy herbicides
GIT effects–> vomiting, diarrhea; some neurological–> ataxia, weakness, myotonia
2,4-D pathology
non-specific (congestion, puffy liver)
2,4 - D treatment
-activated charcoal; wash
2,4 - D in public health?
thought to initiate/promote Non Hodgkin’s Lymphoma (tumor of B lymphocytes); limited tissue residues; teratogenic; immunoteratogen (damaged immune system in full-grown mouse pups); immunostimulant of B lymphocytes
examples of Dipyridyl Herbicides
paraquat, diquat, aziquat, etc
paraquat general info
highly toxic, acute toxicity only, not persistent
kinetics of dypryidyl herbicides?
distribution–> lungs
excretion –> urine, unchanged
short half life
mechanism of action of dipyridyl herbicides?
travels to lung–>reduced to a free rad–>oxidized to a superoxide free rad->lipid peroxidation
glyphosphate/roundup general info
broad spectrum, targets photosynthesis; non-volatile, low toxicity, no residue/environmental threat;
effects of glyphosphate
a mild irritant; not carcinogenic/teratogenic; possible immune-mediated effects
why is roundup/glyphosphate an ideal herbicide?
fasting acting, no residues, low toxicity
what is picloram, what is its persistency?
a picolonic acid derivative; persistent–2 year, excreted unchanged in the urine
picloram toxicity?
eye irritation; mild reproductive effects; mild teratogenicity
picloram environmental issues?
no bioconcentration; some aquatic toxicity; use is restricted
