NOTE: WHO: Believed
to be obsolete or discontinued for use as pesticides.
from FAN: it is permitted for use in India).
26, 2002 - European Commission: Dimefox
is one of 320 pesticides to be withdrawn in July 2003. "Some
320 substances used in plant protection products (PPPs)
Ü including insecticides, fungicides and herbicides Ü are
to be withdrawn from the market by 25 July 2003 as part
of the European Commission's new approach to the evaluation
of active substances in plant protection products.
highly toxic cholinesterase inhibitor.
[Budavari, S. (ed.). The Merck Index - An
Encyclopedia of Chemicals, Drugs, and Biologicals. Whitehouse
Station, NJ: Merck and Co., Inc., 1996. 542]
no-effect dosage of dimefox based on the most sensitive
criterion, red cell cholinesterase, is 0.002 mg/kg/day in
W.J., Jr., E.R. Laws, Jr., (eds.). Handbook of Pesticide
Toxicology. Volume 2. Classes of Pesticides. New York, NY:
Academic Press, Inc., 1991. 974]
IS INCL ON LIST OF COMPD CONSIDERED MOST DANGEROUS TO PESTICIDE
/FROM TABLE/ [Sunshine, I. (ed.). CRC Handbook
of Analytical Toxicology. Cleveland: The Chemical Rubber
Co., 1969. 563]
mainly from: Profile for Dimefox from Hazardous Substances
(click on for all fluorinated pesticides)
Abstract: The toxicological effects of schradan (152169), dimefox
(115264), and parathion (56382) were investigated in rats,
pigs, and humans. Schradan was given to rats on diet at concentrations
from 0.05 to 5.0 parts per million (ppm) or by intraperitoneal
(ip) injection of 0.007 to 2.5 milligrams per kilogram (mg/kg).
Pigs were fed 0.1 to 2.5ppm in diet. Human
subjects were given 1.4mg 5 days per week to a total of 44mg.
Brain and plasma cholinesterase (ChE) were determined
in animals. Blood ChE was determined in humans.
Rats were fed 0.01 to 5.0ppm dimefox in diets for 28 to 287 days.
Pigs received 0.005 to 0.5ppm for 133 days.
Humans were given oral doses of 0.0014mg/kg for 14 days, then
0.004mg/kg for 95 days, or 0.0012, 0.002, or 0.0034mg/kg for 70
days. Inhibition of ChE was determined. For parathion,
rats were fed 0.05, 0.5, or 5.0ppm in diet for 84 days. Pigs were
fed 0.02 to 100ppm in increasing doses from 33 to 122 days. Humans
received oral doses of 0.6mg per day until week 4, then increased
to 4.8mg to week 13; 7.2mg for 6 weeks; or 1.2 or 2.4mg for 25
to 70 weeks. ChE inhibition was determined. The no effect concentrations
were determined for each of the compounds. For schradan, the no
effect dose was 0.02mg/kg per day for rats and pigs. In man, 3ppm
presented no hazard. Based on changes in
red cell ChE, the no effect concentrations of dimefox were 0.003,
0.006, and 0.002mg/kg per day for rat, pig, and man, respectively.
Obvious ill effects or illness in man would occur at about 100
times that concentration...
Ref: Edson EF (1964). Summaries of Toxicological
Data. No-Effect Levels of Three Organophosphates in the Rat, Pig
and Man. Food and Cosmetics Toxicology, Vol. 2, pages 311-316.
Abstract available at FAN's abstracts for Dimefox:
Excerpt from abstract:
The neurobehavioral toxicity of the organophosphate pesticides
sumithion (122145), dimefox (115264),
and trichlorphon (52686) was evaluated in rats. Rats were administered
perorally 10 milligrams per kilogram per day (mg/kg/day) sumithion,
0.25mg/kg/day dimefox... Acetylcholinesterase
activity decreased significantly in the case of dimefox
K (1982). Effect Of Pesticides On Central And Peripheral Nervous
System Function In Rats. Neurobehavioral Toxicology and Teratology,
Vol. 4, No. 6, pages 665-669. Abstract available at FAN's abstracts
on for all fluorinated pesticides)
Abstract: The neurobehavioral
toxicity of three organophosphate pesticides, sumithion, dimefox
and trichlorphon, was evaluated in rats using measures of open
field activity, rotorod performance, conditioned escape from shock,
and nerve conduction velocity. These measures were correlated
with blood and brain cholinesterase level determinations. All
three chemicals disrupted behavior ranging from transient disruptions
accompanied by alterations in nerve conduction to disruption throughout
the exposure. Even in the case of prolonged behavioral disruption,
however, some recovery of performance occurred. Cholinesterase
in both blood and brain decreased with initial dosing and remained
low with continued dosing regardless of changes in the behavioral
measures. The results are discussed in terms of the necessity
of using mammalian behavioral tests to determine the toxicity
of organophosphorous compounds in order to safeguard the health
of the human population.
Ref: Lehotzky K (1982). Effect
of pesticides on central and peripheral nervous system function
in rats. Neurobehav Toxicol Teratol. Nov-Dec;4(6):665-9.
on for all fluorinated pesticides)
PubMed abstract: ...
In addition, a series of pesticides structurally related to HMPA,
such as dimefox, hexamethylmelamine,
hexazinone, alachlor, CAM, pirimicarb, dimetilan, thiram and methabenzthiazuron
have been tested with the Oregon-K strain. Some of these pesticides
had already been shown to be genotoxic in other systems, whereas
others have either not been tested or gave negative results in
in vitro systems. Although genotoxicity was expressed only within
a narrow dose range, all pesticides were
genotoxic in the w/w+ system with the Oregon-K strain.
Thus, these compounds may be a genotoxic hazard to man...
Ref: Mutagenesis 1994 Jul;9(4):341-6. The
w/w+ SMART is a useful tool for the evaluation of pesticides
by Aguirrezabalaga I, Santamaria I, Comendador MA.