Ecological Assessment of Storm Impacts

Data Collection

Methidathion

Basic Information

Synonym(s): S-((5-methoxy-2-oxo-1,3,4-thiadiazol-3(2H)-yl)methyl) O,O-dimethyl phosphorodithioate; Somanil; Somonil; Supracide; Suprathion; Ultracide; phosphorodithioic acid
Formula: C₆H₁₁N₂O₄PS₃
Molecular Weight: 302.318
Melting Point (°C): 39 - 40
Contaminant Type: Methidathion is an insecticide.

Solubility (in water)

• Solubility: 240 mg/l ^ah
  Temperature (°C): 20
  

• Solubility: 240 mg/l ^d
  Temperature (°C): 20
  

• Solubility: 250 mg/l ^k
  Temperature (°C): 20
  

• Solubility: 240 mg/l ^k
  Temperature (°C): 25
  

Half-Life (in soil unless otherwise noted)

• t1/2: 5-23 days ^h
  

Toxicity Effects

• Organism Type: Birds ^h
  Common Name: Chukar partridge
  Scientific Name: Alectoris chukar
  Toxicity: 225 mg/kg
  Test: LD50
  

• Organism Type: Birds ^h
  Common Name: Mallard
  Scientific Name: Anas platyrhynchos
  Toxicity: 23-33 mg/kg
  Test: LD50
  

• Organism Type: Birds ^h
  Common Name: Canada Goose
  Scientific Name: Branta canadensis
  Toxicity: 8.41 mg/kg
  Test: LD50
  

• Organism Type: Birds ^h
  Common Name: ring-necked pheasant
  Scientific Name: Phasianus colchicus
  Toxicity: 33.2 mg/kg
  Test: LD50
  

• Organism Type: Fish ^ak
  Common Name: Carp
  Scientific Name: Cyprinus carpio
  Toxicity: 2.5 mg/l
  Test: 48h LC50
  

• Organism Type: Fish ^k
  Common Name: Bluegill
  Scientific Name: Lepomis macrochirus
  Toxicity: 2 µg/l
  Test: 96h LC50
  

• Organism Type: Fish ^h
  Common Name: Bluegill
  Scientific Name: Lepomis macrochirus
  Toxicity: 2 - 9 µg/l
  Test: 96h LC50
  

• Organism Type: Fish ^ak
  Common Name: Rainbow trout
  Scientific Name: Oncorhynchus mykiss
  Toxicity: 2 - 10 µg/l
  Test: 96h LC50
  

• Organism Type: Fish ^k
  Common Name: Rainbow trout
  Scientific Name: Oncorhynchus mykiss
  Toxicity: 10 µg/l
  Test: 96h LC50
  

• Organism Type: Fish ^h
  Common Name: Rainbow trout
  Scientific Name: Oncorhynchus mykiss
  Toxicity: 10 - 14 µg/l
  Test: 96h LC50
  

• Organism Type: Mammals ^ak
  Common Name: Guinea pig
  Toxicity: 20-80 mg/kg bw
  Test: LD50
  

• Organism Type: Mammals ^h
  Common Name: Guinea pig
  Toxicity: 25 mg/kg
  Test: LD50
  

• Organism Type: Mammals ^h
  Common Name: Dog
  Scientific Name: Canis (Genus)
  Toxicity: 200 mg/kg
  Test: LD50
  

• Organism Type: Mammals ^ak
  Common Name: Rabbits
  Scientific Name: Lagomorpha (order)
  Toxicity: 20-80 mg/kg bw
  Test: LD50
  

• Organism Type: Mammals ^h
  Common Name: Rabbits
  Scientific Name: Lagomorpha (order)
  Toxicity: 80 mg/kg
  Test: LD50
  

• Organism Type: Mammals ^ak
  Common Name: Rat
  Scientific Name: Muridae (Family)
  Toxicity: 20-80 mg/kg bw
  Test: LD50
  

• Organism Type: Mammals ^ak
  Common Name: Mouse
  Scientific Name: Muridae (Family)
  Toxicity: 20-80 mg/kg bw
  Test: LD50
  

• Organism Type: Mammals ^h
  Common Name: Mouse
  Scientific Name: Muridae (Family)
  Toxicity: 18-25 mg/kg
  Test: LD50
  

• Organism Type: Mammals ^ah
  Common Name: Rat
  Scientific Name: Muridae (Family)
  Toxicity: 25-54 mg/kg
  Test: LD50
  

Soil Organic Carbon/Water Partition Coefficients

• Koc: 20 ^ak
  

• Koc: 194 ml/g ^k
  Formulation: sand
  pH Value: 7.8
  

• Koc: 456 ml/g ^k
  Formulation: sandy loam
  pH Value: 6.7
  

• Koc: 217 ml/g ^k
  Formulation: silty loam'
  pH Value: 6.1
  

• Koc: 2.29-2.79 ^k
  Formulation: log
  

Octanol-Water Partition Coefficients

• Log Kow: 2.2 ^ak
  

• Log Kow: 4.7243 ^h
  Notes: Source did not specify type of partition coeffecient or if value was the log

• Log Kow: "2.22, 2.42" ^k
  

Work Cited