ENDOSULFAN

Endosulfan is a chlorinated cyclodiene compound historically used as a broad-spectrum, non-systemic contact and stomach insecticide and acaricide.
Technical Endosulfan is a mixed-isomer material composed mainly of alpha-Endosulfan and beta-Endosulfan, commonly in an approximate 70:30 ratio.
Technical Endosulfan and its related isomers are listed for elimination under international persistent-organic-pollutant controls, and all former specific exemptions for pesticide production and use have expired.
Present procurement is therefore centered on laboratory-scale research, analytical reference standards, residue monitoring, environmental assessment, and the characterization of legacy stocks and contaminated materials.

CHEMICAL IDENTITY AND COMMON NAMES

The CAS identity 115-29-7 describes Endosulfan as the mixed-isomer substance rather than either isolated stereoisomer.
Alpha-Endosulfan is separately identified by CAS 959-98-8, while beta-Endosulfan is separately identified by CAS 33213-65-9.
Endosulfan sulfate, CAS 1031-07-8, is an oxidation product and environmentally important residue component, not a synonym for Endosulfan.

Synonyms and Common Names: Endosulphan, Endosulfan (ISO), Technical Endosulfan, Endosulfan technical grade, Endosulfan mixed isomers, (1,4,5,6,7,7-Hexachloro-8,9,10-trinorborn-5-en-2,3-ylenebismethylene)sulfite, 1,4,5,6,7,7-Hexachloro-8,9,10-trinorborn-5-en-2,3-ylenedimethyl sulphite, 6,7,8,9,10,10-Hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,4,3-benzodioxathiepin-3-oxide, 6,9-Methano-2,4,3-benzodioxathiepin, 6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-, 3-oxide, 5-Norbornene-2,3-dimethanol, 1,4,5,6,7,7-hexachloro-, cyclic sulfite, 1,4,5,6,7,7-Hexachloro-5-norbornene-2,3-dimethanol cyclic sulfite, Sulfurous acid cyclic ester with 1,4,5,6,7,7-hexachloro-5-norbornene-2,3-dimethanol, alpha,beta-1,2,3,4,7,7-Hexachlorobicyclo(2.2.1)-2-heptene-5,6-bisoxymethylene sulfite, 1,2,3,4,7,7-Hexachlorobicyclo(2.2.1)hepten-5,6-bioxymethylenesulfite, Hexachlorohexahydromethano-2,4,3-benzodioxathiepin-3-oxide, 1,9,10,11,12,12-Hexachloro-4,6-dioxa-5-thiatricyclo[7.2.1.0(2,8)]dodec-10-ene 5-oxide, 1,9,10,11,12,12-Hexachloro-4,6-dioxa-5lambda4-thiatricyclo[7.2.1.0(2,8)]dodec-10-ene 5-oxide

TECHNICAL IDENTIFICATION

CAS Number: 115-29-7
EC / EINECS Number: 204-079-4
Molecular Formula: C9H6Cl6O3S
Molar Mass: 406.93 g/mol
Alpha-Endosulfan CAS Number: 959-98-8
Beta-Endosulfan CAS Number: 33213-65-9
Endosulfan Sulfate CAS Number: 1031-07-8
CIPAC Number: 89
UN Number for Solid Endosulfan: UN 2761
InChIKey: RDYMFSUJUZBWLH-UHFFFAOYSA-N

PHYSICAL AND CHEMICAL PROPERTIES

Chemical Class: Organochlorine cyclodiene pesticide and cyclic sulfite ester
Physical State: Crystalline solid
Appearance, Pure Isomers: Colorless crystals
Appearance, Technical Material: Cream to brown granules, flakes, or powder with a tendency to agglomerate
Odor: Characteristic, terpene-like to slightly sulfur dioxide-like
Melting Range, Technical Material: 70–100 °C
Melting Point, Alpha-Endosulfan: 108–110 °C
Melting Point, Beta-Endosulfan: 208–210 °C
Density: 1.745 g/cm³ at 20 °C
Water Solubility, Mixed Isomers: Approximately 0.33 mg/L at 25 °C
Water Solubility, Alpha-Endosulfan: 0.53 mg/L at 25 °C
Water Solubility, Beta-Endosulfan: 0.28 mg/L at 25 °C
Solubility in Acetone: Approximately 262 g/L at 20 °C
Solubility in Toluene: Approximately 200 g/L at 20 °C
Solubility in Xylene: Approximately 388 g/L at 20 °C
Solubility in Hexane: Approximately 24 g/L at 20 °C
Vapor Pressure, Technical Material: Approximately 1 × 10⁻⁵ mmHg at 25 °C
Log Kow: 3.83 for Alpha-Endosulfan and 3.62 for Beta-Endosulfan
Log Koc: 4.03 for Alpha-Endosulfan and 4.13 for Beta-Endosulfan
Combustibility: The neat solid is not combustible, although solvent-based formulations and analytical solutions may be flammable
Thermal Behavior: Decomposes on heating and releases toxic or irritating fumes containing sulfur oxides and chlorine-containing products
Hydrolytic Behavior: Hydrolyzes in aqueous acidic and alkaline media to Endosulfan diol with release of sulfur dioxide, with faster breakdown under alkaline conditions
Oxidative Behavior: Slowly oxidizes to Endosulfan sulfate in air and reacts more rapidly with strong oxidizing agents
Material Compatibility: Attacks iron

FUNCTIONAL CHARACTERISTICS

Endosulfan historically controlled susceptible insects and mites through contact and ingestion rather than through systemic movement within the plant.
Its insecticidal action results from antagonism of GABA-gated chloride channels, which disrupts inhibitory nerve transmission and produces nervous-system excitation.

The low water solubility and comparatively high affinity for organic phases supported oil-based and emulsifiable formulations but also promoted association with soil, sediment, organic matter, and biological lipids.
Low ambient vapor pressure limits rapid evaporation from the neat solid, while sufficient semivolatility permits atmospheric transport after dispersion.

The two stereoisomers have different melting points, water solubilities, and toxic potencies, making isomer ratio important in technical-material characterization and analytical work.
Beta-Endosulfan can isomerize irreversibly to the more thermodynamically stable alpha form, with temperature influencing the conversion.
Oxidation produces Endosulfan sulfate, which retains substantial toxicological and environmental importance and is therefore measured separately in residue and environmental programs.

PRODUCTION AND COMMERCIAL FORM

Industrial production historically began with the addition reaction of hexachlorocyclopentadiene and cis-butene-1,4-diol to form a bicyclic diol.
Esterification and ring closure with thionyl chloride then produced the cyclic sulfite structure and the characteristic alpha/beta isomer mixture.

Technical Endosulfan was supplied as cream-to-brown granules, flakes, or powder containing at least 94% total Endosulfan, with the alpha:beta ratio commonly near 70:30.
Historical formulated forms included dustable powder, wettable powder, oil-miscible liquid, and emulsifiable concentrate.
These forms were designed respectively for dry distribution, water suspension, oil dilution, or water-emulsion preparation and are not interchangeable with analytical-reference materials.

Present laboratory supply forms are principally neat mixed-isomer reference material, isolated alpha- or beta-isomer material, Endosulfan sulfate reference material, and certified solutions of defined concentration in a stated solvent.
The certified identity, isomer composition, concentration, solvent, uncertainty, traceability, container size, storage condition, and expiry period determine the suitability of these laboratory forms.

APPLICATIONS AND INDUSTRIES

Endosulfan was historically applied in agriculture as a broad-spectrum insecticide and acaricide against chewing and sucking pests.
Documented crop contexts included cotton, coffee, tea, tobacco, beans, cowpeas, groundnuts, maize, rice, wheat, potatoes, tomatoes, eggplant, okra, onions, mango, and other fruit and vegetable crops.
Target organisms included aphids, whiteflies, thrips, jassids and leafhoppers, bollworms, stem and fruit borers, leaf miners, caterpillars, scale insects, mealybugs, fruit flies, and mites.

Coffee production used Endosulfan historically against coffee berry borer and stem borers, while cotton production used it against bollworms and several sap-feeding pests.
Tea and tobacco production also employed it against pest complexes involving aphids, caterpillars, leafhoppers, thrips, budworms, and other insects.
Limited historical use also occurred in wood preservation.
These agricultural and preservative uses are historical product functions, and the former international use exemptions have expired.

Current professional use is concentrated in analytical chemistry and laboratory-scale research.
Food and feed laboratories use Endosulfan standards for pesticide-residue method development, calibration, recovery studies, quality control, and the identification of legacy residues.
Environmental laboratories use mixed-isomer, individual-isomer, and sulfate standards to measure residues in water, soil, sediment, air, vegetation, and biological samples.

Toxicology and ecotoxicology programs use controlled laboratory quantities to study neurotoxicity, environmental transformation, bioaccumulation, and the behavior of Endosulfan sulfate and other transformation products.
Forensic and occupational laboratories may include Endosulfan in targeted or multi-residue screening methods for exposure investigations.
Contaminated-site assessment, legacy-stock characterization, waste classification, and remediation monitoring require accurate differentiation among alpha-Endosulfan, beta-Endosulfan, Endosulfan sulfate, and other degradation products.

GRADE SELECTION AND PRODUCT SUITABILITY

Mixed-isomer Endosulfan under CAS 115-29-7 is appropriate when a method or study addresses technical Endosulfan as a whole.
Alpha-Endosulfan and beta-Endosulfan standards are required when chromatographic separation, isomer-specific recovery, environmental transformation, or individual residue reporting is involved.
Endosulfan sulfate requires its own reference material because it has a different formula, molar mass, chromatographic response, environmental behavior, and CAS identity.

For neat analytical material, the principal selection parameters are chemical identity, assay, isomer composition, chromatographic purity, homogeneity, traceability, storage condition, and expiry period.
For certified solution standards, concentration and uncertainty, solvent identity, solution stability, ampoule or bottle volume, and metrological traceability become additional selection parameters.

Legacy technical material is characterized by total Endosulfan assay, alpha:beta ratio, water content, acidity, acetone-insoluble matter, appearance, and the presence of oxidation or hydrolysis products.
A conventional technical-material benchmark uses at least 940 g/kg total Endosulfan, an alpha:beta ratio from 60:40 to 75:25, water content not exceeding 10 g/kg, acetone-insoluble matter not exceeding 10 g/kg, and acidity not exceeding 1 g/kg calculated as sulfuric acid.

Historical wettable powders, dustable powders, oil-miscible liquids, and emulsifiable concentrates require formulation-specific tests such as active-ingredient content, moisture, acidity or alkalinity, sieve residue, wettability, suspensibility, emulsion stability, persistent foam, low-temperature stability, and elevated-temperature stability.
Such pesticide formulations belong to a distinct and heavily controlled regulatory category rather than the present analytical-reference market.

FORMULATION AND PROCESS CONSIDERATIONS

The extremely low water solubility of Endosulfan makes direct preparation of aqueous stock solutions unsuitable for quantitative analytical work.
Analytical solutions are prepared in a compatible organic solvent selected for the instrument, method, calibration range, and sample matrix.
The solvent and concentration stated on a certified standard form part of the material identity used in calculations.

Alkaline conditions accelerate hydrolysis, while strong oxidizing conditions promote formation of Endosulfan sulfate.
Moisture, elevated temperature, reactive metals, and incompatible reagents are therefore controlled during sample preparation, standard storage, and legacy-material handling.
Glass or another demonstrated compatible contact material is preferred where iron attack or catalytic degradation is a concern.

Powder handling requires enclosed transfer, local exhaust ventilation, and dust control because hazardous airborne concentrations can develop when the material is dispersed.
Analytical workflows benefit from dedicated glassware or rigorously validated cleaning, low-carryover injection sequences, and separate treatment of high-concentration standards and trace-level samples.
Solution-standard handling also incorporates the flammability and inhalation hazards of the stated solvent.

QUALITY, SPECIFICATIONS AND DOCUMENTATION

Gas chromatography provides effective separation and quantitative determination of alpha-Endosulfan and beta-Endosulfan, while mass-spectrometric or other orthogonal identification strengthens selectivity in complex matrices.
An analytical scope that reports total Endosulfan commonly includes alpha-Endosulfan, beta-Endosulfan, and Endosulfan sulfate, with the calculation convention stated explicitly in the method.

The Certificate of Analysis identifies the material, CAS number, lot, assay or certified concentration, measurement uncertainty where applicable, isomer composition, solvent for solution standards, traceability, expiry, and storage conditions.
The Safety Data Sheet defines hazard classification, exposure controls, emergency measures, transport information, and disposal requirements.
The Technical Data Sheet describes the supplied form, intended technical use, principal properties, packaging, and storage parameters.

Procurement documentation for Endosulfan also records the intended laboratory or reference-standard use, destination jurisdiction, required analyte form, pack size, and applicable import or transport authorization.
For environmental and residue programs, specifying all required analytes at the quotation stage prevents confusion between mixed Endosulfan, the individual isomers, and Endosulfan sulfate.

SAFETY AND REGULATORY CONSIDERATIONS

Endosulfan is acutely toxic by ingestion and inhalation and is harmful through skin contact.
The substance can be absorbed through the lungs, gastrointestinal tract, and skin, and its principal acute target is the central nervous system.
Exposure may produce headache, dizziness, nausea, vomiting, weakness, confusion, tremor, convulsions, respiratory difficulty, unconsciousness, and potentially fatal respiratory failure.

Harmonized Hazard Classification: Acute Toxicity Category 2 by oral and inhalation routes, Acute Toxicity Category 4 by the dermal route, Aquatic Acute Category 1, and Aquatic Chronic Category 1
Hazard Statements: H300, H330, H312, H400, H410
Signal Word: Danger
Occupational Exposure Reference: 0.1 mg/m³ as an eight-hour time-weighted average with skin notation

Endosulfan is very toxic to aquatic organisms and can cause long-lasting environmental effects.
Its persistence, semivolatility, potential for long-range transport, association with sediments and biological tissues, and formation of persistent Endosulfan sulfate make environmental release prevention a central handling requirement.

International POP Status: Technical Endosulfan and its related isomers are listed in Annex A of the Stockholm Convention for elimination
Specific Exemption Status: No registered specific exemptions remain, and the former production and agricultural-use exemptions have expired
Laboratory Context: The Annex A production and use restrictions do not apply to quantities used for laboratory-scale research or as reference standards under Article 3(5) of the Stockholm Convention
International Trade Status: Endosulfan is listed as a pesticide in Annex III of the Rotterdam Convention and is subject to the prior informed consent procedure

Procurement for laboratory research or reference-standard use remains subject to the applicable national authorization, import, export, transport, recordkeeping, waste, and workplace controls.
The destination, intended use, quantity, chemical form, and documentation package therefore form essential parts of a compliant Endosulfan order.

FIRST AID

Inhalation: Move the exposed person to fresh air, keep at rest, support breathing if required, and obtain urgent medical attention.

Skin Contact: Remove contaminated clothing and footwear immediately, wash the skin thoroughly with soap and water for at least 15 minutes, and obtain medical attention.

Eye Contact: Rinse cautiously with clean water for at least 15 minutes, remove contact lenses when easily possible, continue rinsing, and obtain medical attention.

Ingestion: Rinse the mouth, do not induce vomiting, give nothing by mouth to an unconscious or convulsing person, and obtain emergency medical assistance immediately.

Note to Physicians: Endosulfan has no specific antidote, so management is supportive and symptom-directed with immediate attention to airway, oxygenation, circulation, recurrent seizures, status epilepticus, acid-base balance, cardiac rhythm, renal function, and complications of prolonged convulsions.
Gastrointestinal decontamination is a clinical decision requiring airway protection because convulsions and aspiration can occur, and oil-based cathartics are avoided because they can enhance absorption.

HANDLING AND STORAGE

Handling: Use closed handling wherever practicable, prevent dust and aerosol formation, avoid all skin and eye contact, and prohibit eating, drinking, or smoking in the work area.

Ventilation: Provide effective local exhaust ventilation at transfer, weighing, dissolution, and sampling points.
Personal Protection: Wear chemical-resistant gloves, protective clothing, eye and face protection, and suitable respiratory protection selected for the exposure assessment and material form.

Hygiene: Wash thoroughly after handling, remove contaminated clothing immediately, and keep work clothing within the controlled workplace.

Storage: Keep locked, dry, tightly closed, and in a cool, well-ventilated hazardous-material area with secondary containment.

Incompatibilities: Segregate from acids, bases, strong oxidizing agents, iron, food, beverages, and animal feed.

Fire: Use extinguishing media suitable for the surrounding fire, cool exposed containers with water spray, contain contaminated firefighting water, and use full protective equipment with self-contained breathing apparatus.

Spill Response: Isolate the area, prevent dust, drains, soil, and surface-water contamination, and have trained personnel collect the material into covered sealable hazardous-waste containers using chemical protective clothing and respiratory protection.

Disposal: Manage Endosulfan, contaminated absorbents, packaging, firefighting water, and legacy stocks as regulated hazardous persistent-organic-pollutant waste through an authorized destruction or disposal route.

PACKAGING AND PROCUREMENT CONSIDERATIONS

Endosulfan packaging requires a tightly closed, chemically compatible primary container, tamper-evident closure, secondary containment, clear hazardous-chemical identification, and protection from moisture, heat, breakage, and unauthorized access.
Analytical reference materials are commonly packaged in small sealed containers or ampoules suited to controlled laboratory use, while legacy technical material requires hazardous-goods packaging appropriate to its physical form and quantity.

Transport Classification for Solid Endosulfan: UN 2761, organochlorine pesticide, solid, toxic, Class 6.1, Packing Group II, marine pollutant
Transport Separation: Do not transport with food or animal feed

Solvent-based standards may receive a transport description governed by the complete solution composition, including solvent flammability and Endosulfan concentration.
A procurement request identifies CAS 115-29-7, 959-98-8, 33213-65-9, or 1031-07-8 as applicable and states the required neat or solution form, assay or concentration, solvent, certification, pack size, destination, intended use, and documentation.

For Endosulfan analytical standards, isomer selection, certified concentration, specifications, documentation, packaging, and compliant supply requirements, contact Ataman Kimya at +90 216 577 10 10 or info@atamankimya.com.