impaginato piccolo - Società Italiana di Parassitologia (SoIPa)

100
pyriproxyfen is twice as biologically active as diflubenzuron,
and therefore commercial formulations containing
pyriproxyfen can be used that release smaller
amounts of active ingredient into the environment.
Usually pyriproxyfen-based commercial products contain
a quarter of the active ingredient contained in
diflubenzuron-based products whilst providing similar
persistence.Spreading the larvicidal treatments over
intervals longer than 3-4 weeks results in a risk of
Composition Composition Usage rates taken from technical data sheets and referring
to a street manhole with 40 litres water
Pyriproxyfen 4%
Diflubenzuron 15%
A. Baseggio - Mosquitoes control products
Water microemulsion
Suspension concentrate
The the list of insecticidal active ingredients for
which companies are currently producing the
review dossiers required by the BPD shows that
underestimating the operative structure (i.e. the number
of operators occupied in the territory) and therefore
in the inability to manage unplanned treatments,
for example after heavy rainfall. In Japan it has been
observed that Ae. albopictus can develop resistance to
pyriproxyfen and diflubenzuron but it is a long process
(Kasai S. et al, 2007, J. Med. Entomol. 44 (5): 822-
829).
2) For adulticidal treatments
Table 1. comparison between the usage rates of common liquid larvicides containing IGR active ingredients
Etofenprox is a phenoxyderivative substance marked
by a mode of action similar to that of pyrethroids but
with a particularly reduced acute toxicity (LD50 acute
oral rat = 42880 mg/kg; acute dermal > 2140 mg/kg;
0.25 ml of product per manhole
0.28 ml of product per manhole
pyrethroids will mainly be available in the future
(Table 2)
Etofenprox has interesting toxicological characteristics;
Table 2. list of pyrethroids whose dossiers will most likely be submitted for review; synthetic data on acute toxicity.
Active ingredient LD50 acute
oral rat mg/kg
d-Phenotrin
Permethrin
Deltamethrin (in water)
Tetramethrin
d-Tetramethrin
Transfluthrin
Cypermethrin
Deltamethrin (in naphta)
Alpha-cypermethrin
Esbiothrin
Natural pyrethrin
Cyphenothrin
Esfenvalerate
Lambda-cyalothrin
Bifenthrin
I = irritating
Inhalation toxicity (4h) =5900 mg/m 3)
Average usage rates of a few insecticides available on
the market:
Two OP active ingredients will also be available in addi-
Composition (%) Formulation type Average rates for adult mosquitocontrol
Cypermethrin 10
Tetramethrin 2
Piperonyl Butoxide 5
Permethrin 15
Tetramethrin 2.5
Piperonyl Butoxide 5
Deltamethrin 1
Esbiothrin 2.5
Piperonyl Butoxide5
Etofenprox 10
Piperonyl Butoxide 20
> 10000
6000
> 5000
> 5000
> 5000
> 5000
250 – 4150
800
474
> 432
570-150
318
88,5
79
> 53,4
Water microemulsion
Water microemulsion
Suspension concentrate
Water microemulsion
LD50 acute
dermal mg/kg
> 10000
> 2500
> 2000
> 5000
> 5000
> 5000
> 4820
> 2000
> 2000
> 2000
1500
> 5000
> 5000
696
> 2000
LC50 Inhalation
toxicity (4h)
> 2100 mg/l
> 685 mg/l
> 22 mg/l
2,73 mg/l
> 1,18 mg/l
> 0,513 mg/l
> 25 mg/l
> 22 mg/l
> 0,32 mg/l
2,63 mg/l
3,4 mg/l
> 1,85 mg/l
> 0,48 – 0,57 mg/l
0,06 mg/l
> 0,8 mg/l
0.5%
0.8%
0.75%
0.5%
Properties
Non photostable
Photostable
Photostable I
Non photostable
Non photostable
Non photostable
Photostable, I
Photostable, I
Photostable
Non photostable
Non photostable
Photostable
Photostable, I
Photostable, I
Photostable