Lannate

1
Lannate Insecticide

• Registration
• Attributes
• Lannate compared to OPs products
• Reversibility Studies in Rat
• Mexican worker exposure
• DuPont Safe Use Measures Proposal

2
Methomyl Registration

• Lannate has been commercialized since 1968 (USA)
• Widely registered
• 80 countries
• approximately 190 crops (vegetables, fruits,
  fibers, and plantation crops)
• Variety of formulations available to meet local
  needs
• No severe restrictions or bans based on risk
  assessment
• Is not PIC listed

3
Insecticidal Attributes

• Lannate is anti-acetyl cholinesterase, inhibiting
  nerve function
• Broad spectrum of activity controls gt140 insect
  species
• Fast acting, effective by contact ingestion
  also ovicidal activity
• Not phytotoxic, systemic, translaminar
• Excellent compatibility with commonly used
  pesticides
• Resistance management tool and fits with IPM

4
Toxicology Attributes

• Acute dermal toxicity is extremely low
• one of the primary attributes of methomyl
• 95 of worker exposure is potentially dermal
• Acute oral and inhalation toxicity is high
• exposure can be mitigated (masks)
• Toxicity (acetyl cholinesterase inhibition) is
  quickly reversible without treatment
• carbamate insecticide property
• no delayed neurotoxicity in long term
• Effective antidote is available (atropine)
• Toxicology studies have shown that methomyl does
  not cause developmental toxicity, reproductive
  toxicity, mutations, chronic toxicity, delayed
  neurotoxicity, carcinogenicity

5
Environmental Attributes

• Rapid decomposition to natural molecules, no
  potential to bioaccumulate
• Rapid degradation
• soil 90 loss in 35 days, low mobility
• water half life very short, hours to lt7 days
• Rapid metabolism
• plants half life lt3-5 days, short residual on
  crops, safe for harvesters (PHIs 1-7 days) and
  consumers
• animals gt50 metabolized or excreted in 24 hrs
• Aquatic toxicity
• acutely toxic to invertebrates but exposure
  mitigated by label precautions (no aquatic uses)
• low potential for chronic toxicity due to rapid
  degradation

6
Lannate Vs. commonly used OPs

• Dermal and dietary safety in comparison to some
  OP insecticides
• Dermal LD50 ADI
• (mg/kg) (ug/kg/day)
• methomyl 5880 (rabbit) 30
• methamidophos 118 (rabbit) 0.6
• monocrotophos 354 (rabbit) 120 (rat) 0.6
• demeton S methyl 30 (rat) 0.3
• oxydemeton methyl 130 (rat) 0.3
• mevinphos 16-33 (rabbit) 4-90 (rat) 1.3
• ADI Acceptable Daily Intake values determined
  by JMPR

7
Lannate Rat Reversibility Study Results
8
Mexican Worker Exposure Study

• Determine potential dermal and respiratory
  exposure to mixers, loaders, and applicators
  during use with backpack sprayers
• low (cauliflower) and medium (tomato) height
  crops
• 15 replicates (5 operators spraying on 3 separate
  occasions)
• GIFAP recommended clothing worn
• outer cotton tunic and trousers with inner cotton
  underwear (dosimeter f/dermal exposure)
• waterproof gloves with cotton undergloves
  (dosimeter f/hand exposure)
• rubber boots, baseball caps dust masks
  (dosimeter f/respiratory exposure)

9
Mexican Worker Exposure Study Summary of
Findings

• Outer clothing provides a high degree of
  protection from dermal exposure intercepting
  83-93 of total methomyl residue
• Respiratory exposure is very low (lt0.1)dust
  mask
• Margins of safety for workers applying methomyl
  to a medium height crop (tomato) with appropriate
  PPE are
• 206 for dermal exposure
• 3316 for respiratory exposure

10
Mexican Worker Exposure Study Results
11
Mexican Worker Exposure Study Results
Methomyl residues
12
Mexican Worker Exposure Study Tomato Results
Route Exposure NOEL MOS Dermal 0.437
mg/kg 90 mg/kg 206 (sum of deposits on
inner suit and gloves, face, and
neck) Respiratory 0.0038 mg/kg 12.6
mg/kg 3316 (deposit on respirator)
based on a 70 kg person and adjusted to 6 and 4
hrs exposure for dermal and respiratory routes,
respectively 21-day dermal study in
rabbits (exposure 6 hrs/day) rat
inhalation LC50 study (exposure 4 hrs no
mortality at 1.8 mg/L) assumes 100 absorption
by a 0.25 kg rat with a
respiration rate of 73 mL/min Margin of
Safety NOEL divided by exposure
13
DuPont Safe Use Measures

• Use of dye (color)
• New formulations with bittering agents (mal
  sabor) to prevent accidental ingestion
• Use of constant flow valve for backpack sprays
• Labelling with precautions and pictograms
• Availability of atropine whenever needed
• Safe use training programs
• Packaging in water soluble bags for solids and
  high density plastic bottles for liquids no
  large containers

14
DuPonts proposal to authorities

• Discontinue commercialization of liquid Lannate
• New 1 oz presentation on WSB to avoid handling
• Training to medical department, to be able to
  tell difference between acetyl cholinesterase
  symptoms and other (heat)
• Continue training efforts on good use and Lannate
  management
• On the last 3 years, 430 people were trained in
  El Salvador
• Agricultores, cooperativas,
• Distribuidores
• dependientes de mostrador,
• Area de ventas, servicio tecnico, bodegueros.