Organophosphate Poisoning: What You Should Know

Medically Reviewed by Poonam Sachdev on November 11, 2021

Every year, more than three million people worldwide are exposed to organophosphates, chemical compounds that kill insects and plant pests. Of those, 8,000 exposures occur annually in the U.S. and may lead to organophosphate poisoning. 

What Are Organophosphates? 

Organophosphates are chemical compounds that control insects. They are typically used in agriculture or household items like ant and cockroach spray. Organophosphates are also used as medication or as nerve gases. They disrupt the nervous systems of mosquitos and other plant pests. These chemicals are poisonous and may be lethal to humans. 

Common organophosphates that harm humans include: 

  • Chlorpyrifos
  • Diazinon
  • Dursban
  • Fenthion
  • Malathion
  • Parathion

Exposure to a large amount of these chemical compounds can poison your body and make you sick. 

Humans absorb organophosphates in three ways:

  • Inhalation
  • Skin contact
  • Ingestion (eating or drinking)

How quickly you experience symptoms depends on the type and amount of exposure. For example, if you're a farmer spraying organophosphates to prevent insects from destroying your crops, you could end up inhaling the poison if the wind changes suddenly. If you inhaled a large quantity, you may notice severe symptoms immediately. 

Symptoms often occur within minutes, and sometimes persist for weeks. 

Early symptoms, which occur 24 to 96 hours after you're exposed, include: 

Other symptoms that may persist for weeks or months include: 

In some cases, organophosphate poisoning leads to death. 

If you've been exposed to organophosphate, your doctor will have to wear personal protective equipment (PPE) during your treatment to prevent his or her own exposure. 

The first step is decontamination. Your clothing will be removed and destroyed, as the chemicals can remain on your clothing even after washing. Your doctor may decontaminate your skin with water or use flour, sand, or bentonite clay

If you've ingested the poison, you may be experiencing symptoms such as vomiting or diarrhea, which will decontaminate your digestive system. Your doctor will use intravenous fluids to help flush your system and remove any additional toxins. 

Doctors will monitor your lungs and airways. Meanwhile, if you're experiencing any kind of spasms or seizures, you may need to be intubated. This procedure involves placing a tube in your throat and windpipe to open up your airways and help you breathe. 

Sometimes, a drug called atropine is used as an organophosphate antidote to help stabilize your breathing. Another medication called pralidoxime can reduce neuromuscular symptoms. If you are experiencing seizures, your doctor may use certain benzodiazepines like valium or xanax to prevent or stop these symptoms. 

If you're exposed to a large amount of organophosphates (referred to as acute exposure) and survive, you may notice certain neurological symptoms and complications that persist for months or even years, including: 

Some studies on organophosphate poisoning report that patients experience neurological or psychiatric symptoms for years after long term exposure. 

Show Sources


Centers for Disease Control and Prevention: "Adulticides." 

Centers for Disease Control and Prevention: "Nerve Agent and Organophosphate Pesticide Poisoning." 

Merck Manual Professional Version: "Organophosphate Poisoning and Carbamate Poisoning." 

National Center for Biotechnology Information: "Clinical features of organophosphate poisoning: A review of different classification systems and approaches."

National Center for Biotechnology Information: "Effects of Long-Term Exposure to Organophosphate Pesticides in Humans." 

National Center for Biotechnology Information: "Organophosphate Toxicity." 

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