Introduction 

Demeton is an organophosphate pesticide. This pesticide is used as both Insecticide and Acaricide. These have been widely used in agriculture to protect crops against destructive pests like aphids, mites, and other sap-sucking insects. Like many organophosphates, it acts as a potent acetylcholinesterase inhibitor, disrupting the nervous systems of insects. While it has contributed to pest management success in farming, its toxicological risks to humans, animals, and the environment cannot be ignored. 

This blog will provide a practical and authoritative reference on Demeton. Also, this blog will cover its properties, applications, hazards, exposure limits, and safe handling practices. Whether you are an agricultural professional, an industrial user, or an EHS (Environment, Health, and Safety) manager, understanding these details is crucial for responsible use and compliance with global safety standards. 

 

Chemical and Physical Properties 

Demeton is found in two isomeric forms: Demeton-O and Demeton-S. Both forms exhibit similar pesticidal activity. This chemical structure consists of phosphorus atoms. These atoms are bonded to oxygen and sulfur groups and contribute to their high reactivity and toxicity. 

  • Chemical Formula: C7H17O3PS2 
  • Molecular Weight: Approximately 246.33 g/mol 
  • Appearance: Clear to pale yellow liquid 
  • Odor: Characteristic mercaptan-like smell 
  • Boiling Point: Around 226°C 
  • Solubility: It is slightly soluble in water. It is highly soluble in organic solvents like Ethanol and Acetone. 
  • Density: Approximately 1.2 g/cm³ 

 

These properties make Demeton highly effective in penetrating pest cuticles and acting rapidly. However, its low water solubility and volatility require careful application of techniques to avoid unintended environmental contamination. 

 

Industrial and Laboratory Applications 

Agricultural Applications 

Demeton’s primary application lies in agriculture, where it is widely used to control aphids, mites, and other harmful insects that affect crops such as cereals, vegetables, and fruits. Its rapid action and broad-spectrum effectiveness make it a preferred choice for pest management in large-scale farming operations. 

Industrial and Laboratory Applications 

Beyond agriculture, Demeton finds applications in industrial pest control, particularly in managing pest infestations in storage facilities and greenhouses. In laboratory settings, Demeton is used in research to study the effects of organophosphates on insect and mammalian cholinesterase enzymes, which are critical for understanding toxicological mechanisms. 

Despite its usefulness, many countries have imposed strict regulations or bans on Demeton due to its hazardous nature. Alternatives with lower toxicity profiles are increasingly favored in sustainable agricultural practices, but Demeton remains in use where stringent safety measures are in place. 

 

Hazard Profile 

Demeton is highly toxic to humans, animals, and aquatic life. Its mode of action involves inhibiting acetylcholinesterase, an enzyme essential for nerve function. This inhibition causes an accumulation of acetylcholine at nerve synapses, leading to continuous nerve impulse transmission, muscle spasms, and potentially fatal respiratory paralysis. 

Health Hazards 

  • Acute Toxicity:  

Exposure to Demeton can occur via inhalation, dermal absorption, or ingestion. Symptoms of acute poisoning include headaches, dizziness, nausea, vomiting, abdominal cramps, excessive salivation, sweating, muscle twitching, and in severe cases, convulsions and death. 

  • Chronic Effects: 

 Long-term exposure can result in neurological damage, memory loss, and persistent cognitive impairment. Studies have shown that organophosphate exposure can have lasting effects on the nervous system, especially in occupational settings. 

  • Environmental Impact: 

 Demeton is highly toxic to aquatic organisms and beneficial insects such as bees. Its persistence in the environment is moderate, with degradation influenced by pH, temperature, and microbial activity. 

 

Regulatory Status 

Due to its hazardous profile, many countries have imposed restrictions or complete bans on Demeton usage. The European Union classifies it as a substance of very high concern (SVHC), and its use is strictly regulated under pesticide regulations. 

Occupational Exposure Limits 

Occupational Exposure Limits Table

 

 

 

 

 

To mitigate the risks associated with Demeton, regulatory agencies have established occupational exposure limits (OELs) that must be adhered to in workplaces where Demeton is handled. 

  • OSHA Permissible Exposure Limit (PEL): No specific PEL for Demeton, but general organophosphate limits apply, typically set at 0.1 mg/m³ as a time-weighted average (TWA) over an 8-hour workday. 
  • NIOSH Recommended Exposure Limit (REL): Generally recommended at 0.1 mg/m³ TWA. 
  • ACGIH Threshold Limit Value (TLV): Like NIOSH recommendations, 0.1 mg/m³ TWA. 

Employers always keep an eye on the air quality in the workplace and implement engineering controls, such as proper ventilation and closed systems, to maintain exposure levels below these limits. Personal protective equipment (PPE) is essential to further reduce risk. 

 

Safety and Handling Recommendations 

Due to its high toxicity and environmental risks, stringent safety protocols must be followed when handling Demeton. 

Personal Protective Equipment (PPE) 

  • Chemical-resistant gloves (nitrile or neoprene) are mandatory. 
  • Protective clothing (coveralls and chemical-resistant aprons) are necessary. 
  • Proper Eye protection (chemical safety goggles or face shields) is required. 
  • Respiratory protection (as per NIOSH-approved organic vapor respirators) 

Storage and Handling 

  • Store in a cool, dry, and well-ventilated area, away from incompatible substances like strong oxidizers and alkalis. 
  • Keep containers tightly closed and properly labeled. 
  • Avoid storing near food, beverages, or animal feed to prevent accidental contamination. 

 Spill and Disposal Procedures 

  • In case of spills, evacuate the area and use appropriate PPE to contain and clean up the chemical using absorbent materials. 
  • Dispose of Demeton waste in accordance with local hazardous waste regulations. Never pour it down drains or sewers. 

 First Aid Measures 

  • Inhalation: Move the affected person to fresh air immediately and administer oxygen if breathing is difficult. Seek medical attention without delay. 
  • Skin Contact: Remove contaminated clothing and wash the affected area thoroughly with soap and water. 
  • Eye Contact: Rinse eyes immediately with plenty of water for at least 15 minutes and seek medical attention. 
  • Ingestion: Do not induce vomiting. Administer activated charcoal if recommended by a medical professional and seek immediate medical help. 

 Training and Awareness 

Training programs should be provided for all personnel who are going to handle the Demeton. These programs need to cover safe handling practices, proper use of personal protective equipment (PPE), emergency procedures, and following regulations. Regular audits and refresher courses can help maintain safety standards. 

 

Conclusion 

Demeton is an effective organophosphate pesticide. It is widely used in agriculture and industry for pest control. However, it is very toxic to humans, animals, and the environment. This toxicity requires careful handling and strict safety protocols. It’s important to understand its chemical properties, uses, hazards, and exposure limits to protect the health and safety of workers and the environment. 

Employers must carry out thorough training programs, provide proper PPE, and enforce strict storage, handling, and disposal practices. With responsible management and compliance with safety standards, the benefits of Demeton’s pest control can be used safely and sustainably.