Organochlorine Pesticide Toxicity Clinical Presentation

Updated: May 14, 2022
  • Author: Matthew L Wong, MD, MPH; Chief Editor: Michael A Miller, MD  more...
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The history of exposure to an organochlorine pesticide is the most important piece of information to obtain. In many cases the exact history will not be known, and efforts to identify the offending agent should be made. Information on the toxin involved is valuable because organochlorine exposure may produce the same clinical manifestations as other poisons that are much more commonly available, particularly in the United States. Furthermore, there should be concern about inadvertent exposure to healthcare providers, as well as to laypeople in contact with the patient.

At a minimum, the history should include the following:

  • Prior medical and psychiatry history
  • Nonprescription drugs used
  • Natural or herbal preparations used
  • Allergies to medications
  • Patient activity for that day of exposure
  • Occupational history, including farming; field work; and chemical or pesticide manufacturing, handling, or application
  • Pest control use
  • Location in relation to industrial facilities or waste sites
  • Hobbies (eg, gardening)

If possible, obtain the product in its original container. Review the label and contact the poison control center. Save the sample for possible testing and identification. Usually, testing has to be performed at an outside laboratory and has no immediate clinical impact on the patient's treatment.

United States law requires that pesticide package labels contain certain information regarding product classification and toxicity, which is based on animal oral studies of median lethal dose. The following are classifications for the toxic categories:

  • Danger - High toxicity
  • Warning - Moderate toxicity
  • Caution - Low toxicity
  • No signal word - Safe

Onset of symptoms is characteristically abrupt. Central nervous system (CNS) excitation and depression are the primary effects observed in acute organochlorine toxicity; therefore, the patient may appear agitated, lethargic, intoxicated, or may even be unconscious. Initial euphoria with auditory or visual hallucinations and perceptual disturbances are common in the setting of acute toxicity.

Organochlorines lower the seizure threshold, which may precipitate seizure activity. Strong external stimuli and reflex hyperexcitability may precipitate muscle fasciculations and tonic spasms, which may evolve into seizures.

Patients may have pulmonary complaints or may be in severe respiratory distress. Cardiac dysrhythmias may complicate the initial clinical presentation.

Other symptoms include the following:

  • Pulmonary - Cough, shortness of breath
  • Dermatologic - Rash
  • Gastrointestinal - Nausea, vomiting, diarrhea, and abdominal pain
  • Nervous system - Headache, dizziness, or paresthesias of the face, tongue, and extremities

Physical Examination

Because of the high lipid solubility, duration of toxicity can be prolonged. Life-threatening complications are seizures secondary to prolonged CNS stimulation and consequent hypoxia.

Physical examination findings vary by type of exposure, as follows:

  • Ingestion
  • Skin absorption or inhalation
  • Chronic exposure

Ingestion produces the following manifestations:

  • Nausea and vomiting
  • Confusion, tremor, myoclonus, coma, and seizures
  • Respiratory depression or failure
  • Unusual odor - Toxaphene may have a turpentine-like odor; endosulfan may have a sulfurous odor

Skin absorption or inhalation produces the following manifestations:

  • Ear, nose, and throat irritation
  • Blurred vision
  • Cough
  • Acute lung injury (ALI)
  • Dermatitis

Long-term occupational exposure to organochlorine pesticides may result in various nonspecific symptoms, including headaches, nausea, fatigue, muscle twitching, and visual disturbances. In addition, chronic exposure to these agents may be associated with the development of blood dyscrasias, including aplastic anemia and leukemia in humans (inconclusive).

Other manifestations of chronic exposure are as follows:

  • Anorexia
  • Hepatotoxicity
  • Renal toxicity
  • CNS disturbances