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Name: O,O-Diethyl-S-(P-Nitrophenyl) Phosphorothioate
Common Synonym: Parathion
Classification: Organophosphate pesticide
Appearance: Clear yellow to brown liquid
Odor: Characteristic, somewhat unpleasant
Use: Controls insects on crops and sometimes gets discussed in stories about farmworker safety and rural communities living close to fields
CAS Number: 56-38-2
Acute Toxicity: Extremely toxic by oral, dermal, and inhalation routes; causes rapid poisoning, especially when the skin barrier gets bypassed by cuts or prolonged contact
Chronic Effects: Interrupts nervous system function; headaches, tremors, and possible memory trouble show up in people exposed regularly
Environmental Hazard: Seriously toxic to aquatic life, often causing fish kills in contaminated waters and putting amphibians at risk
Skin And Eye Contact: Burns and pain possible on contact; even a small amount absorbed through skin turns serious
Combustibility: Supports burning, gives off toxic fumes when heated
Main Component: O,O-Diethyl-S-(P-Nitrophenyl) Phosphorothioate
Concentration: Above 95% in technical-grade formulations
Impurities: By-products like diethyl phosphoric acid may show up; these rarely pose the same immediate risks, but it’s the main ingredient sparking concern
Inhalation: Move person to fresh air immediately; shut off exposure if possible and get medical attention; convulsions or unconsciousness can put a rescue at risk for both helpers and victims
Skin Contact: Rinse skin under running water; remove contaminated clothing without risking more exposure; use soap, not just water, for thorough decontamination
Eye Contact: Rinse eyes gently but thoroughly with clean water for several minutes; keep eyelids apart, and don’t delay getting emergency care
Ingestion: Never induce vomiting; seek immediate professional help, as delayed response can make outcomes far worse; activated charcoal sometimes gets used in emergency rooms
Proper Extinguishing Agents: Dry chemical, carbon dioxide, or foam; water jet can spread contamination
Protective Gear: Firefighters need full protection, including breathing apparatus; burning product lets off phosphorus oxides and nitrogen oxides, neither of which anyone wants to inhale
Fire Hazards: Heating breaks product down into even nastier gases; always keep containers well away from open flame or high heat
Personal Precautions: Keep people away from spill area; avoid breathing fumes; skin exposure brings immediate risk
Protective Equipment: Gloves, goggles, protective suits with sealed seams; regular clothes offer no defense
Containment: Stop discharge from going into drains and waterways; absorb with earth, sand, or inert material, never sawdust
Cleanup Methods: Collect material in sealed, labeled containers; avoid creating dust or aerosol; ventilate space after cleaning up, and wash all equipment thoroughly
Safe Handling: Always use in well-ventilated areas, preferably with a fume hood; never eat, drink, or smoke where handling takes place
Storage Conditions: Keep containers tightly closed and stored in cool, dry, dark places; separate from food, animal feed, and incompatible chemicals like strong bases or oxidizers
Spill Preparedness: Emergency washing stations close to work areas respond to accidental contact; keeping PPE within easy reach helps
Workplace Monitoring: Continuous monitoring recommended in manufacturing or application spaces
Respiratory Protection: Use full-face respirators with organic vapor cartridges for area workers
Hand Protection: Chemical-resistant gloves, like those made of neoprene or nitrile
Eye Protection: Safety goggles or face shields; dust or droplets from mixing require both
Hygiene Measures: No eating, drinking, or smoking in workspaces; handwashing before and after handling always minimizes accidental ingestion
Physical State: Oily liquid
Color: Yellow to brown
Boiling Point: About 375°C (707°F)
Melting Point: -6°C (21°F)
Density: 1.27 g/cm³
Vapor Pressure: Very low at room temperature, but inhalation risk rises in hot climates or heated workspaces
Solubility: Barely dissolves in water; dissolves well in organic solvents like acetone and ethanol
Chemical Stability: Remains stable in unopened containers under dry conditions
Reactivity: Breaks down quickly with strong oxidizing agents or in alkaline environments; sunlight and high heat speed up breakdown
Decomposition Products: Burns or breakdown releases phosphorus oxides, sulfur oxides, and nitrogen oxides, turning a chemical accident into an air pollution problem
Routes of Exposure: Entry through skin, lungs, and digestive tract
Short-term Risks: Nausea, convulsions, muscle twitches, sweating, pinpoint pupils, and even coma in severe cases; organophosphates block cholinesterase, a critical nerve enzyme; effects start fast, and delay can be fatal
Long-term Risks: Repeat exposure links to neurological disorders, memory problems, anxiety, depression
Vulnerable Groups: Children and farmworkers take the hardest hit, with developing brains and prolonged contact making outcomes worse
Aquatic Toxicity: Fish and aquatic invertebrates show high mortality at low concentrations; environmental contamination wipes out local populations and disrupts food chains
Persistence: Breaks down in soil and water over weeks, but breakdown speed depends on light, heat, and microbial activity; risks linger in colder or low-sunlight conditions
Bioaccumulation: Potential for buildup in aquatic life, making local fish unsafe to eat after accidental spills or improper disposal
Product Disposal: Must not go in regular trash or down the drain; high-temperature incineration with pollution controls often needed
Container Disposal: Rinsing tries to reduce leftovers, but empty containers still bring risk, so proper hazardous waste disposal always matters
Shipping Precautions: Classified as highly toxic; special marking, secure packaging, and documentation just to move containers from one site to another
Transport Risk: Accidents create big environmental problems fast; responders need specialized training and equipment while dealing with leaks
Legislation Notes: Use faces restrictions or outright bans in some countries; strict rules oversee application, disposal, and import
Worker Safety Standards: Exposure guidelines set by occupational health regulators, aiming to keep air levels far below the point where symptoms set in
Reporting Requirements: Large spills and worker poisonings demand quick reporting to local authorities; fines and penalties hold companies accountable for violations
