Pediatric Mercury Toxicity Follow-up

  • Author: David K Tan, MD, EMT-T, FAAEM; Chief Editor: Timothy E Corden, MD   more...
 
Updated: Jun 30, 2010
 

Further Inpatient Care

  • All patients in unstable condition should be admitted to an ICU.
  • After the patient is admitted, continue supportive measures, decontamination, and careful monitoring.
  • In cases of inorganic mercuric salt ingestion, carefully monitor the patient's renal function.
Next

Further Outpatient Care

  • After chelation therapy is completed and the patient's condition is stable, careful follow-up with the patient's regular physician is mandatory.
  • Monitor the patient's blood mercury concentrations for several months to ensure that the exposure is not ongoing.
Previous
Next

Inpatient & Outpatient Medications

  • After inpatient chelation therapy is completed, outpatient chelation therapy is unnecessary.
Previous
Next

Transfer

  • After initial stabilization, transfer the patient to a higher level of care is indicated if the capabilities of the treating hospital are inadequate.
  • For example, transfer is advised in the following situations:
    • No ICU is available.
    • No chelating agents are in stock.
    • Mercury concentrations cannot be tested in the laboratory.
Previous
Next

Deterrence/Prevention

  • Minamata disease is best prevented by reducing or eliminating one's consumption of fish caught from bodies of water that are contaminated with high concentrations of mercury.
  • Other forms of mercury exposure, such as elemental mercury vapor inhalation, occur when people vacuum or sweep mercury spills in an enclosed space. The proper authorities must handle any spill with the appropriate mercury decontamination kits and procedures.
Previous
Next

Complications

  • Minamata disease has devastating neurologic consequences as a primary outcome of methyl mercury intoxication; unfortunately, these are relatively resistant to treatment.
    • Acute perioral and facial paresthesias develop.
    • Respiratory distress and nonspecific dermatitis can also occur.
    • Extremity numbness eventually appears along with headache, fatigue, and tremor.
    • Ataxia and dysarthria can also be observed.
    • Severe poisoning eventually causes the patient to lie in a mute semirigid posture that is broken only by episodes of crying or primitive reflexive movements.
  • Babies exposed in utero are the most severely affected.
    • They are affected by low birth weight, seizure disorders, profound developmental delay, incomplete visual loss (including tunnel vision), total blindness, and hearing loss.
    • Long-term studies indicate that even prenatal exposure at low concentrations can cause subtle but detectable decrements in the areas of motor function, language, and memory.
    • Children so affected may have long-term stigmata, including motor impairment, visual loss, hearing loss, developmental delay, and seizure disorders.
Previous
Next

Prognosis

  • Once the neurologic sequelae of Minamata disease are evident, the damage is irreversible, and severe intoxications have been fatal. However, the damage may be minimized if detected early enough.
  • Effects of long-term exposure are only now being fully recognized. Most survivors of Minamata disease have chronic neuropathologic conditions such as the following:
    • Ataxia
    • Psychiatric disturbances
    • Sensory loss
    • Chronic paresthesias
  • Compared with other patients, babies exposed to Minamata disease in utero have a more dismal prognosis. Their sequelae include the following:
    • Severe developmental delay
    • Low birth weight
    • Persistent cognitive impairment
Previous
Next

Patient Education

  • Minamata disease typically occurs in areas in which the population depends on seafood as a dietary staple and in areas in which industrial wastes contaminate the drinking water. Educate patients about alternative food sources and about eliminating their intake of contaminated fish.
  • Outbreaks of methyl mercury poisoning also have occurred after the introduction of fungicide-treated grain into the food supply. Neither humans nor livestock should eat seed grain treated with mercurial fungicides.
  • For excellent patient education resources, visit eMedicine's Poisoning Center and Poisoning - First Aid and Emergency Center. Also, see eMedicine's patient education articles Poisoning and Activated Charcoal.
Previous
 
Contributor Information and Disclosures
Author

David K Tan, MD, EMT-T, FAAEM  Assistant Professor and Chief, EMS Section, Division of Emergency Medicine, Medical Director, Washington University EMS, Washington University in St Louis School of Medicine

David K Tan, MD, EMT-T, FAAEM is a member of the following medical societies: American Academy of Emergency Medicine and National Association of EMS Physicians

Disclosure: Nothing to disclose.

Coauthor(s)

Michael E Mullins, MD  Assistant Professor, Department of Emergency Medicine, Washington University School of Medicine

Michael E Mullins, MD is a member of the following medical societies: American Academy of Clinical Toxicology and American College of Emergency Physicians

Disclosure: Johnson & Johnson stock ownership None; Savient Pharmaceuticals stock ownership None

Specialty Editor Board

William T Zempsky, MD  Associate Director, Assistant Professor, Department of Pediatrics, Division of Pediatric Emergency Medicine, University of Connecticut and Connecticut Children's Medical Center

William T Zempsky, MD is a member of the following medical societies: American Academy of Pediatrics

Disclosure: Nothing to disclose.

Mary L Windle, PharmD  Adjunct Associate Professor, University of Nebraska Medical Center College of Pharmacy; Pharmacy Editor, eMedicine

Disclosure: Nothing to disclose.

Jeffrey R Tucker, MD  Assistant Professor, Department of Pediatrics, Division of Emergency Medicine, University of Connecticut and Connecticut Children's Medical Center

Disclosure: Merck Salary Employment

Daniel Rauch, MD, FAAP  Director, Pediatric Hospitalist Program, Associate Professor, Department of Pediatrics, New York University School of Medicine

Daniel Rauch, MD, FAAP is a member of the following medical societies: Ambulatory Pediatric Association, American Academy of Pediatrics, and Society of Hospital Medicine

Disclosure: Baxter Honoraria Consulting

Chief Editor

Timothy E Corden, MD  Associate Professor of Pediatrics, Co-Director, Policy Core, Injury Research Center, Medical College of Wisconsin; Associate Director, PICU, Children's Hospital of Wisconsin

Timothy E Corden, MD is a member of the following medical societies: American Academy of Pediatrics, Phi Beta Kappa, Society of Critical Care Medicine, and Wisconsin Medical Society

Disclosure: Nothing to disclose.

References

  1. Harada M. Minamata disease: methylmercury poisoning in Japan caused by environmental pollution. Crit Rev Toxicol. 1995;25(1):1-24. [Medline].

  2. Amin-zaki L, Majeed MA, Clarkson TW, Greenwood MR. Methylmercury poisoning in Iraqi children: clinical observations over two years. Br Med J. Mar 11 1978;1(6113):613-6. [Medline].

  3. Feng X, Li P, Qiu G, Wang S, Li G, Shang L, et al. Human exposure to methylmercury through rice intake in mercury mining areas, Guizhou province, China. Environ Sci Technol. Jan 1 2008;42(1):326-32. [Medline].

  4. Madsen KM, Lauritsen MB, Pedersen CB, et al. Thimerosal and the occurrence of autism: negative ecological evidence from Danish population-based data. Pediatrics. Sep 2003;112(3 Pt 1):604-6. [Medline]. [Full Text].

  5. Andersen AH. Experimental studies on the pharmacology of activated charcoal; III. Acta Pharmacol. 1948;4:275-84.

  6. Cercy SP, Wankmuller MM. Cognitive dysfunction associated with elemental mercury ingestion and inhalation: a case study. Appl Neuropsychol. 2008;15(1):79-91. [Medline].

  7. Davis LE, Kornfeld M, Mooney HS, et al. Methylmercury poisoning: long-term clinical, radiological, toxicological, and pathological studies of an affected family. Ann Neurol. Jun 1994;35(6):680-8. [Medline].

  8. Eisler R. Mercury hazards from gold mining to humans, plants, and animals. Rev Environ Contam Toxicol. 2004;181:139-98. [Medline].

  9. Grandjean P, Weihe P, White RF, Debes F. Cognitive performance of children prenatally exposed to "safe" levels of methylmercury. Environ Res. May 1998;77(2):165-72. [Medline].

  10. Isik S, Güler M, Oztürk S, Selmanpakoglu N. Subcutaneous metallic mercury injection: early, massive excision. Ann Plast Surg. Jun 1997;38(6):645-8. [Medline].

  11. Knobeloch LM, Ziarnik M, Anderson HA, Dodson VN. Imported seabass as a source of mercury exposure: a Wisconsin case study. Environ Health Perspect. Jun 1995;103(6):604-6. [Medline].

  12. Magos L. Three cases of methylmercury intoxication which eluded correct diagnosis. Arch Toxicol. Nov 1998;72(11):701-5. [Medline].

  13. Malm O. Gold mining as a source of mercury exposure in the Brazilian Amazon. Environ Res. May 1998;77(2):73-8. [Medline].

  14. Mayo Clinic Health Letter. Mercury in fish: concerns shouldn't dampen your appetite. 1996 Apr.

  15. Morgan JN, Berry MR, Graves RL. Effects of commonly used cooking practices on total mercury concentration in fish and their impact on exposure assessments. J Expo Anal Environ Epidemiol. Jan-Mar 1997;7(1):119-33. [Medline].

  16. Nuttall KL. Interpreting hair mercury levels in individual patients. Ann Clin Lab Sci. 2006;36(3):248-61. [Medline].

  17. Pierce PE, Thompson JF, Likosky WH, Nickey LN, Barthel WF, Hinman AR. Alkyl mercury poisoning in humans. Report of an outbreak. JAMA. Jun 12 1972;220(11):1439-42. [Medline].

  18. Sue, Young-Jin. Mercury. In: Goldfrank LR, Flomenbaum NE, Lewin NA, eds. Goldfrank's Toxicologic Emergencies. 1319-29.

  19. Uchino M, Tanaka Y, Ando Y, Yonehara T, Hara A, Mishima I, et al. Neurologic features of chronic minamata disease (organic mercury poisoning) and incidence of complications with aging. J Environ Sci Health B. Sep 1995;30(5):699-715. [Medline].

  20. Yotsuyanagi T, Yokoi K, Sawada Y. Facial injury by mercury from a broken thermometer. J Trauma. May 1996;40(5):847-9. [Medline].

 
Previous
Next
 
 
 
 
All material on this website is protected by copyright, Copyright © 1994-2012 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.