Chemistry of ENDOSULFAN

                                                          ENDOSULFAN

 

CHEMICAL NAME: 6,7,8,9,10,10-Hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-

                                       methano-2,4,3-benzodioxathiopin-3-oxide (56)

 

Structure  of  ENDOSULFAN Molecule

DEC INGRED. CODE:

 

TRADE NAME(S): Thiodan, Tiovel (56)

 

FORMULATION(S): Wettable powders (35, 50%), emulsifiable concentrates(17.5%,35%,50%, and 2 pounds and 3 pounds/gallon),

ULV (25%), granules (2,3,4,5%), dusts (1,2,3,4,5,6%)

TYPE: Organochlorine insecticide - miticide

 

BASIC PRODUCER(S): FMC Corp. Velsicol Chemical Corp.Agr. Chem. Group 341 East      Ohio Street2000 Market St. Chicago, IL 60611Philadelphia, PA 19103

STATUS: Restricted use

 

PRINCIPAL USES:Controls aphids, thrips, beetles, foliar feeding

larvae, mites, borers, cutworms, bollworms, bugs, whiteflies, leaf-hoppers, and slugs on deciduous, citrus, and small fruits, vegetables, forage crops, oil crops, fiber crops, grains, tobacco, coffee, tea,forest, ornamentals. Controls termites and tsetse fly.

 

I. EFFICACY

Important Pests Controlled: Aphids, beetles, bollworms, spittlebugs,termites, tsetse fly, leafhoppers, pear psylla, fleabeetles, stemborers, stinkbugs, boll weevils, loopers, corn earworms, peach twig borers,armyworms, cyclamen mites, mosquito pupae, and many others.

 

II. PHYSICAL PROPERTIES

MOLECULAR FORMULA: C9 H6 Cl6 O3 S (62)

 

MOLECULAR WEIGHT: 406.9 (62)

 

PHYSICAL STATE:  Brown crystalline solid (technical product, at least 94% pure). Endosulfan is a mixture of two stereo-isomers: alpha-endosulfan, endosulfan (I), m.p. 109 C, is 64-67% of the technical grade; beta-endosulfan,endosulfan (II), m.p. 213.3 C, is 29-32%.

 

ODOR: Of sulfur dioxide (technical product)

 

MELTING POINT: 70-100 C (technical product)

 

VAPOR PRESSURE: 1.2 Pa at 80 C (technicalproduct)

 

SOLUBILITY: 0.32 mg/l water (alphaendosulfan),0.33 mg/l water(beta-endosulfan) at 22 C

 

III. HEALTH HAZARD INFORMATION

  OSHA STANDARD: None established

 

NIOSH RECOMMENDED LIMIT: None established

 

ACGIH RECOMMENDED LIMIT: TWA (Time Weighted Average) = 0.1 mg/m3;

                                                                 STEL (Short Term Exposure Level) = 0.3 mg/m3

TOXICOLOGYA. ACUTE TOXICITYDERMAL: LD50 = 359 mg (in oil)/kg Nonirritant

ORAL: LD50 = 80-110 mg tech. (in oil)/kg (rat); 76 mg alpha isomer/kg (rat); 240 mg beta isomer/kg (rat); 76.7 mg tech./kg (dog)

 

INHALATION: LC50 (Thiodan 50 WP) = >2 gm/liter of air (rat)LD50 = 350 mg/m3 when the exposure is four hours (male rat)

 

EYES: Nonirritant

 

B. SUBACUTE AND CHRONIC TOXICITY:

In 2-yr feeding trials rats receiving 30 mg/kg diet showed noill-effect; in 1-yr feeding trials NEL for dogs was 3 mg/kg diet . Dogs tolerated endosulfan orally for a year at dosages up to 0.75

mg/kg, the highest level tested. Oral dosages of about 0.5mg/kg/day (dietary level of 10 ppm) for 2 years were associated withlower survival of female rats and reduced testis weight in males, butthese findings were of doubtful statistical significance.Consistent histopathological findings were apparent only at a dosageten times as great, which produced renal tubular damage and somehydropic change of the liver .

 

IV. ENVIRONMENTAL CONSIDERATIONS

Hazardous to birds, fish, and beneficial insects. Moderatelyhazardous to honey bees. Biological magnification slight. Not recommended for use on Concord grapes. Injury reported on alfalfa,birch and chrysanthemums under greenhouse conditions

(1).It is highly toxic to fish (LC50 (96-hr) for golden ide 2 ug/lwater) but, in practical use, should be harmless to wildlife and to honeybees.

 

Fish: Endosulfan is highly toxic. The LC50 of various fishspecies was determined to range between 0.001 and 0.05 ppm .

 

Wildlife Studies: the LD50 values obtained are as follows:

 

Species                       Male                     Female

 

Bobwhite Quail                                        50                                              56

Japanese Quail                                      106                                             85

Mallard Ducks                                         243                                            205

 

No significant difference in sex .

                          It is metabolised, in plants and mammals, to the correspondingsulphate which is toxicologically similar to endosulfan (the sulphite).

                         For most fruits and vegetables 50% of the residue is lost in 3-7 days.There is no accumulation in milk, fat or muscle and it is excreted asconjugates of the diol and as other highly polar metabolites dependingon the species .

                       Approximate Residual Period: 7-15 days on plant surfaces; 1 season on unexposed surfaces .

 

V. EMERGENCY AND FIRST AID PROCEDURES

 

The chemical information provided below has been condensed from original source documents, primarily from "Recognition and Management of Pesticide Poisonings", 3rd ed. by Donald P. Morgan,which have been footnoted.

If poisoning is suspected, do not wait for symptoms to develop.Contact a physician, the nearest hospital, or the nearest PoisonControl Center.

 

FREQUENT SYMPTOMS AND SIGNS OF POISONING BY ORGANOCHLORINE PESTICIDES

 

APPREHENSION, EXCITABILITY, DIZZINESS, HEADACHE, DISORIENTATION,

WEAKNESS, PARESTHESIAE, muscle twitching, tremor, tonic and clonic

CONVULSIONS (often epileptiform), and unconsciousness are the major

manifestations. Soon after ingestion, nausea and vomiting commonly

occur. When chemicals are absorbed dermally, apprehension, twitching,

tremors, confusion, and convulsions may be the first symptoms.

Respiratory depression is caused by the pesticide and by the petroleum solvents in which these pesticides are usually dissolved. Pallor occurs in moderate to severe poisoning. Cyanosis may result as convulsive activity interferes with respiration .

 

SKIN CONTACT: Remove contaminated clothing and wash skin thoroughly with soap and water. Call a physician immediately .

 

INGESTION: Give a saline emetic (tablespoon of salt in glass of water) and repeat until returns are clear. Call a physician immediately (11c).

 

EYE CONTACT: Flush with plenty of water. Call a physician immediately .