Ethylene dibromide (1,2-dibromoethane, EDB) is a highly toxic halogenated hydrocarbon historically used as a lead scavenger in gasoline and as a grain/fruit fumigant. Acute poisoning is rare but carries an extremely high mortality rate, with most reported cases resulting in death from multiorgan failure (hepatic, renal) and intractable metabolic acidosis. [1-2] There is no specific antidote; management is entirely supportive. [2-3]
1. History
- Route of exposure: ingestion (suicidal, accidental), inhalation (occupational, confined spaces), or dermal contact [4]
- Timing of exposure, duration, estimated volume/concentration
- Occupational context: fumigation work, grain storage, chemical tank cleaning, leaded gasoline handling [1][4]
- Intentional vs. accidental exposure
- Symptom onset: nausea, vomiting, diarrhea, abdominal pain (ingestion); cough, dyspnea, chest tightness (inhalation); skin blistering (dermal) [4]
- Progression: initial GI/respiratory symptoms → CNS depression → hepatorenal failure over 12–72 hours [1-2]
- Important negatives: co-ingestants, ethanol use (may modulate metabolism), fasting state (enhances hepatotoxicity) [5]
2. Alarm Features
- Altered mental status or rapid loss of consciousness (especially after inhalation in confined spaces) [1]
- Intractable metabolic acidosis — hallmark of severe poisoning and poor prognosis [1-2]
- Oliguria/anuria suggesting acute renal failure
- Coagulopathy or DIC
- Rapidly rising transaminases indicating fulminant hepatic necrosis
- Seizures or cardiovascular collapse
- Any ingestion of concentrated EDB should be treated as potentially lethal — as little as 3 mL of concentrated EDB has caused multiorgan failure [2]
3. Medications
- No specific antidote exists [3]
- N-acetylcysteine (NAC): Theoretical benefit as a glutathione precursor; in vitro data show NAC partially prevents glutathione depletion and lipid peroxidation caused by EDB. Consider empiric use given the mechanism of toxicity (glutathione depletion → hepatocellular necrosis), analogous to acetaminophen poisoning protocols [6-8]
- Avoid hepatotoxic medications and drugs metabolized via CYP2E1 (e.g., ethanol, isoniazid), which may potentiate toxicity [9]
- Avoid alpha-adrenergic agonists (e.g., phenylephrine), which have been shown to potentiate EDB nephrotoxicity in animal models [10]
- Disulfiram and cyanamide (aldehyde dehydrogenase inhibitors) increase susceptibility to EDB toxicity [11]
- Standard antiemetics, vasopressors, and sedatives as needed for supportive care
4. Diet
- NPO in the acute setting
- Fasting state enhances EDB hepatotoxicity in animal models — early nutritional support may be beneficial once GI tract is functional [5]
- No specific long-term dietary considerations beyond standard hepatorenal recovery support
5. Review of Systems
- GI: Nausea, vomiting, diarrhea, abdominal pain, hematemesis
- Neuro: Headache, dizziness, confusion, lethargy, coma
- Respiratory: Cough, dyspnea, chest tightness, pulmonary edema
- Renal: Decreased urine output, hematuria
- Dermatologic: Skin irritation, vesiculation, chemical burns
- Ophthalmologic: Eye irritation, tearing, conjunctival injection
- Hematologic: Bleeding, bruising (coagulopathy)
- Reproductive: Chronic exposure — inquire about infertility, spermatogenic dysfunction [4]
6. Collateral History and Family History
- Coworkers or bystanders with similar symptoms (suggests environmental/inhalation exposure) [1]
- Occupational history: fumigation, agriculture, chemical manufacturing, gasoline handling [4]
- Access to EDB (availability as a fumigant, particularly in South Asia) [2]
- Psychiatric history if intentional ingestion suspected
- Family history is generally not contributory, though GST T1-1 polymorphisms may affect individual susceptibility to EDB metabolism [9]
7. Risk Factors
- Occupational exposure: fumigators, grain handlers, chemical plant workers, tank cleaners [1][4]
- Confined space work without respiratory protection [1]
- Regions where EDB is still used as a fumigant (e.g., India) [2]
- Fasting state (depletes hepatic glutathione, enhances toxicity) [5]
- Pre-existing liver or kidney disease
- CYP2E1 inducers (chronic ethanol use) may increase toxic metabolite formation [9][11]
- Suicidal intent in regions with access to agricultural chemicals
8. Differential Diagnosis
- Carbon tetrachloride or chloroform poisoning — similar hepatorenal toxicity pattern
- Acetaminophen overdose — hepatic necrosis with metabolic acidosis
- Mushroom poisoning (Amanita phalloides) — delayed hepatorenal failure
- Phosphorus poisoning — GI hemorrhage followed by hepatic failure
- Paraquat/diquat ingestion — multiorgan failure with GI corrosion
- Methanol or ethylene glycol poisoning — severe metabolic acidosis with anion gap
- Iron poisoning — GI hemorrhage, metabolic acidosis, hepatic failure
- Other halogenated hydrocarbon exposures (1,2-dichloropropane, methylene chloride)
- Distinguishing features: occupational/exposure history, characteristic sweet chloroform-like odor of EDB, and absence of osmolar gap (unlike toxic alcohols)
9. Past Medical History
- Pre-existing hepatic disease (cirrhosis, hepatitis) — reduced glutathione reserves, increased vulnerability
- Chronic kidney disease — impaired elimination
- Prior EDB or halogenated solvent exposure
- Alcohol use disorder (CYP2E1 induction)
- Nutritional status (malnourished/fasting patients at higher risk) [5]
10. Physical Exam
- Vital signs: Tachycardia, hypotension (late), tachypnea (Kussmaul breathing from acidosis)
- Neuro: Depressed consciousness ranging from lethargy to coma [1]
- Skin: Erythema, vesiculation, or chemical burns at contact sites; diaphoresis [4]
- Eyes: Conjunctival injection, lacrimation, corneal injury
- Pulmonary: Crackles, wheezing, signs of pulmonary edema (inhalation exposure) [12]
- Abdomen: Epigastric tenderness, hepatomegaly (early hepatic congestion)
- Jaundice: May develop within 24–48 hours
- Signs of coagulopathy: Petechiae, ecchymoses, oozing from IV sites
11. Lab Studies
- ABG/VBG: Severe anion gap metabolic acidosis — the hallmark finding [1-2]
- Lactate: Elevated
- Hepatic panel: AST, ALT markedly elevated (may rise within hours); bilirubin elevated [1][5]
- Renal function: BUN, creatinine — rising values indicate acute kidney injury [1-2]
- Coagulation: PT/INR, fibrinogen, D-dimer — coagulopathy/DIC [2]
- CBC: May show decreased RBC, hemoglobin, hematocrit; neutrophilia [13]
- Electrolytes: Hyperkalemia (renal failure), hypoglycemia (hepatic failure)
- Serum glucose: Monitor for hypoglycemia
- Urinalysis: Proteinuria, hematuria; elevated urinary gamma-glutamyltranspeptidase (GGTP) as a marker of renal tubular injury [10]
- LDH: Elevated (marker of cellular injury) [6]
- Toxicology: EDB levels can be measured in blood/urine but are not widely available and rarely guide acute management; urinary metabolites (S-(2-hydroxyethyl)mercapturic acid) may confirm exposure [14]
12. Imaging
- Chest X-ray: Evaluate for pulmonary edema, ARDS (especially after inhalation exposure)
- CT abdomen: If concern for GI perforation or hemorrhagic pancreatitis (not routinely needed)
- Renal ultrasound: If oliguric/anuric to assess for obstruction vs. intrinsic renal injury
- Imaging is generally supportive rather than diagnostic in EDB poisoning
13. Special Tests
- Poison Control Center consultation (800-222-1222) — essential for all cases [15]
- Medical toxicology consultation
- Point-of-care glucose and lactate
- Bedside ultrasound: Assess cardiac function, IVC for volume status, free fluid
- No validated clinical scoring system specific to EDB poisoning
- Environmental/industrial hygiene sampling may confirm exposure source [1]
14. ECG
- Obtain baseline ECG in all cases
- Monitor for hyperkalemia-related changes (peaked T waves, widened QRS) secondary to renal failure
- Nonspecific ST-T wave changes from metabolic derangement
- Arrhythmias possible in the setting of severe acidosis and electrolyte disturbances
15. Assessment
EDB poisoning produces a characteristic clinical syndrome of early GI/CNS symptoms progressing to fulminant hepatorenal failure with intractable metabolic acidosis over 12–72 hours. [1-2] The mechanism involves dual metabolic activation via cytochrome P-450 (producing bromoacetaldehyde) and glutathione S-transferase conjugation (producing a reactive episulfonium ion), both leading to glutathione depletion, lipid peroxidation, DNA adduct formation, and cellular necrosis. [4][6][16]
Key severity indicators:
- Severity correlates with dose, route, and duration of exposure
- Ingestion of even small volumes (≥3 mL concentrated) can be fatal [2]
- Inhalation in confined spaces can cause death within 12 hours [1]
- Survivors of acute poisoning may face long-term carcinogenic risk (EDB is an IARC Group 2A probable human carcinogen) [4][17]
16. Treatment Plan
Initial stabilization
- ABCs — secure airway early if altered mental status; anticipate rapid deterioration [15]
- Aggressive IV fluid resuscitation
- Continuous cardiac monitoring
Decontamination: [3][15]
- Dermal: Remove all contaminated clothing; copious water and soap irrigation
- Ocular: Copious irrigation with saline or water for ≥15 minutes
- GI (ingestion): Gastric lavage if within 60 minutes of ingestion; activated charcoal (1 g/kg) may be considered, though efficacy for EDB is uncertain [3]
- Healthcare worker protection: PPE is critical — EDB is readily absorbed through skin and is volatile [15]
Pharmacologic
- N-acetylcysteine (NAC): Consider empirically using the acetaminophen overdose protocol (IV: 150 mg/kg loading, then 50 mg/kg over 4 hours, then 100 mg/kg over 16 hours) — rationale based on glutathione depletion mechanism [6][8]
- Sodium bicarbonate: For severe metabolic acidosis (pH <7.1)
- Vasopressors: For refractory hypotension (avoid phenylephrine if possible given animal data on potentiation of nephrotoxicity) [10]
- Fresh frozen plasma/cryoprecipitate: For coagulopathy/DIC
- Renal replacement therapy: For refractory acidosis, hyperkalemia, or anuric renal failure
Supportive
- Serial labs every 4–6 hours (hepatic panel, renal function, coagulation, ABG, lactate)
- Strict I&O monitoring
- Glucose monitoring (hepatic failure → hypoglycemia)
- Consider liver transplant evaluation if fulminant hepatic failure develops
17. Disposition
- All symptomatic patients and all intentional ingestions → ICU admission [1-2]
- Any inhalation exposure with CNS depression, respiratory symptoms, or metabolic acidosis → ICU
- Significant dermal exposure with systemic symptoms → admit
- Asymptomatic patients with known exposure → observe minimum 24 hours with serial labs (delayed hepatorenal toxicity is expected)
- Consult: Medical toxicology, nephrology (for RRT), hepatology/transplant surgery if fulminant hepatic failure, psychiatry if intentional ingestion
18. Follow Up / Return Precautions
- Survivors require close hepatology and nephrology follow-up for recovery monitoring
- Serial liver and renal function testing weekly until normalized
- Long-term cancer surveillance given EDB's established genotoxicity and carcinogenicity (nasal cavity, lung, GI, hemangiosarcoma in animal models) [4][17]
- Reproductive counseling: EDB exposure is associated with spermatogenic dysfunction and decreased fertility [4]
- Occupational health referral and workplace safety review for occupational exposures [1]
- Return immediately for: recurrent vomiting, jaundice, decreased urine output, confusion, bleeding, abdominal pain
- Expected recovery course in survivors: hepatic and renal function may take weeks to normalize; coagulopathy typically resolves with hepatic recovery [2]
References
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2. Non-Fatal Ethylene Dibromide Ingestion. — Singh S, Gupta A, Sharma S, et al. Human & Experimental Toxicology. 2000.
3. Recognition and Management of Acute Pesticide Poisoning. — Simpson WM, Schuman SH. American Family Physician. 2002.
4. Ethylene Dibromide: Toxicology and Risk Assessment. — Alexeeff GV, Kilgore WW, Li MY. Reviews of Environmental Contamination and Toxicology. 1990.
5. Modulation of the Mitotic Action of Ethylene Dibromide. — Nachtomi E. Chemico-Biological Interactions. 1980.
6. Toxicity of 1,2-Dibromoethane in Isolated Hepatocytes: Role of Lipid Peroxidation. — Albano E, Poli G, Tomasi A, et al. Chemico-Biological Interactions. 1984.
7. Utility of Acetylcysteine in Treating Poisonings and Adverse Drug Reactions. — Chyka PA, Butler AY, Holliman BJ, Herman MI. Drug Safety. 2000.
8. Use of N-Acetylcysteine in Clinical Toxicology. — Flanagan RJ, Meredith TJ. The American Journal of Medicine. 1991.
9. The Use of Human in Vitro Metabolic Parameters to Explore the Risk Assessment of Hazardous Compounds: The Case of Ethylene Dibromide. — Ploemen JP, Wormhoudt LW, Haenen GR, et al. Toxicology and Applied Pharmacology. 1997.
10. Activation of Alpha(1)-Adrenergic Receptors Potentiates the Nephrotoxicity of Ethylene Dibromide. — Harbison RD, Stedeford T, Muro-Cacho C, Mosquera DI, Banasik M. Toxicology. 2003.
11. Molecular Mechanisms of Dibromoalkane Cytotoxicity in Isolated Rat Hepatocytes. — Khan S, Sood C, O'Brien PJ. Biochemical Pharmacology. 1993.
12. Respiratory Pathology in Rats and Mice After Inhalation of 1,2-Dibromo-3-Chloropropane or 1,2 Dibromoethane for 13 Weeks. — Reznik G, Stinson SF, Ward JM. Archives of Toxicology. 1980.
13. Ethylene Dibromide: Evidence of Systemic and Immunologic Toxicity Without Impairment of in Vivo Host Defenses. — Ratajczak HV, Aranyi C, Bradof JN, et al. In Vivo. 1994.
14. Disposition of 1,2-[14C]Dibromoethane in Male Wistar Rats. — Wormhoudt LW, Hissink AM, Commandeur JN, van Bladeren PJ, Vermeulen NP. Drug Metabolism and Disposition: The Biological Fate of Chemicals. 1998.
15. Hazardous Chemical Emergencies and Poisonings. — Henretig FM, Kirk MA, McKay CA. The New England Journal of Medicine. 2019.
16. Activation of Dihaloalkanes by Glutathione Conjugation and Formation of DNA Adducts. — Guengerich FP, Peterson LA, Cmarik JL, Koga N, Inskeep PB. Environmental Health Perspectives. 1987.
17. Development of an Inhalation Unit Risk Factor for Ethylene Dibromide. — Schaefer HR, Myers JL. Inhalation Toxicology. 2017.