Approach Considerations

The first priority in managing any patient with detectable serum lead is to determine the source of exposure and to remove the person from it. The finding of any elevated serum or urine metal concentration in an asymptomatic person should prompt a thorough dietary, occupational, and recreational history, and radiographs where indicated to identify any source of ongoing exposure. Occupational or recreational histories in parents can also reveal a source of exposure for children.

Laboratory Studies

Specific laboratory testing for metals should be undertaken when the likelihood of toxicity is significant, based on a history and/or symptoms consistent with excessive exposure. See the relevant articles for more detailed recommendations regarding the most reliable testing measures for individual metal toxicity, as follows:

When specific testing is indicated, samples should be sent in metal free containers.

Hair analysis is not generally reliable and rarely indicated.

Patients should be instructed to abstain from seafood and seaweed products prior to testing for metals such as arsenic and mercury, since elevated concentrations in patients who have not done so for at least several days to 1-2 weeks may simply reflect nontoxic organic forms ingested in the diet. Samples with elevated concentrations may also be sent for speciation for either of these metals to determine the relative contributions of organic forms versus inorganic forms.

The following standard laboratory determinations may help make the diagnosis of heavy metal toxicity or help gauge its severity:

Complete blood cell count (CBC) with peripheral smear - Findings may include basophilic stippling of the RBCs on peripheral blood smears; basophilic stippling is not specific for lead toxicity and may be observed in arsenic toxicity, sideroblastic anemia, and thalassemia; the anemia of lead toxicity may be normocytic or microcytic.
Renal function tests
Urine analysis (look for proteinuria)
Liver function studies

Imaging Studies

Abdominal radiographs are indicated in acute ingestions. Radio-opacities demonstrable in the gastrointestinal tract should be cleared by whole-bowel irrigation prior to instituting chelation therapy. Large, retained gastric foreign bodies (eg, bullets, shotgun cartridges, fishing sinkers, curtain weights) may cause lead toxicity and should be removed endoscopically if they do not pass, if serum lead concentrations are concerning or increasing, or if the patient becomes symptomatic.

Several reported cases of patients who have injected elemental mercury subcutaneously and developed mercury toxicity have been documented. Radiographs of the suspect areas showing large subcutaneous deposits of radio-opaque material were helpful in confirming the diagnosis and need for surgical intervention to limit the exposure.

Other Tests

Electrocardiographic abnormalities may provide diagnostic clues in metal toxicity.

Treatment & Management

Tchounwou PB, Yedjou CG, Patlolla AK, Sutton DJ. Heavy metal toxicity and the environment. EXS. 2012. 101:133-64. [QxMD MEDLINE Link].
Saunders JE, Jastrzembski BG, Buckey JC, Enriquez D, MacKenzie TA, Karagas MR. Hearing loss and heavy metal toxicity in a nicaraguan mining community: audiological results and case reports. Audiol Neurootol. 2013. 18(2):101-13. [QxMD MEDLINE Link].
Sue YJ. Mercury. In: Hoffman RS, Howland MA, Lewin NA, Nelson LS, Goldfrank LR, eds. Goldfrank's Toxicologic Emergencies. 10th ed. New York, NY: McGraw-Hill Education; 2015. 1334-1344.
Rathnayake IV, Megharaj M, Krishnamurti GS, Bolan NS, Naidu R. Heavy metal toxicity to bacteria - are the existing growth media accurate enough to determine heavy metal toxicity?. Chemosphere. 2013 Jan. 90(3):1195-200. [QxMD MEDLINE Link].
Schwartz BS, Hu H. Adult lead exposure: time for change. Environ Health Perspect. 2007 Mar. 115(3):451-4. [QxMD MEDLINE Link].
Bowler RM, Roels HA, Nakagawa S, et al. Dose-effect relationships between manganese exposure and neurological, neuropsychological and pulmonary function in confined space bridge welders. Occup Environ Med. 2007 Mar. 64(3):167-77. [QxMD MEDLINE Link].
Agency for Toxic Substances and Disease Registry. Toxicological Profile for Zinc. ATSDR. Available at https://www.atsdr.cdc.gov/toxprofiles/tp.asp?id=302&tid=54. September 30, 2020; Accessed: January 22, 2023.
Munday SW. Arsenic. Hoffman RS, Howland MA, Lewin NA, Nelson LS, Goldfrank LR, eds. Goldfrank's Toxicologic Emergencies. 10th ed. New York: McGraw-Hill Education; 2015.
Calello DP, Henretig FM. Lead. Hoffman RS, Howland MA, Lewin NA, Nelson LS, Goldfrank LR, eds. Goldfrank's Toxicologic Emergencies. 10th ed. New York: McGraw-Hill Education; 2015.
Gummin DD, Mowry JB, Beuhler MC, Spyker DA, Rivers LJ, Feldman R, et al. 2021 Annual Report of the National Poison Data System(©) (NPDS) from America's Poison Centers: 39th Annual Report. Clin Toxicol (Phila). 2022 Dec. 60 (12):1381-1643. [QxMD MEDLINE Link]. [Full Text].
Raymond J, Brown MJ. Blood Lead Levels in Children Aged MMWR Morb Mortal Wkly Rep</i>. 2016 Oct 14. 63 (55):66-72. [QxMD MEDLINE Link]. [Full Text].
Canfield RL, Henderson CR Jr, Cory-Slechta DA, Cox C, Jusko TA, Lanphear BP. Intellectual impairment in children with blood lead concentrations below 10 microg per deciliter. N Engl J Med. 2003 Apr 17. 348(16):1517-26. [QxMD MEDLINE Link].
United States Environmental Protection Agency report. America’s children and the environment. Available at http://www.epa.gov/ace/. Accessed: January 22, 2023.
Alarcon WA, State Adult Blood Lead Epidemiology and Surveillance (ABLES) Program Investigators. Elevated Blood Lead Levels Among Employed Adults - United States, 1994-2013. MMWR Morb Mortal Wkly Rep. 2016 Oct 14. 63 (55):59-65. [QxMD MEDLINE Link]. [Full Text].
Sharp D. In Maine, pains linger for arsenic poisoning survivors. LA Times. June 15, 2008. Available at http://articles.latimes.com/2008/jun/15/news/adna-arsenic15.
Hughes MF, Beck BD, Chen Y, Lewis AS, Thomas DJ. Arsenic exposure and toxicology: a historical perspective. Toxicol Sci. 2011 Oct. 123(2):305-32. [QxMD MEDLINE Link].
Chang TP, Rangan C. Iron poisoning: a literature-based review of epidemiology, diagnosis, and management. Pediatr Emerg Care. 2011 Oct. 27(10):978-85. [QxMD MEDLINE Link].
Clarkson TW, Magos L. The toxicology of mercury and its chemical compounds. Crit Rev Toxicol. 2006 Sep. 36(8):609-62. [QxMD MEDLINE Link].
Chalmers AT, Argue DM, Gay DA, Brigham ME, Schmitt CJ, Lorenz DL. Mercury trends in fish from rivers and lakes in the United States, 1969-2005. Environ Monit Assess. 2011 Apr. 175(1-4):175-91. [QxMD MEDLINE Link].
Parry J. Metal smelting plants poison hundreds of Chinese children. BMJ. 2009 Aug 24. 339:b3433. [QxMD MEDLINE Link].
Watts J. Lead poisoning cases spark riots in China. Lancet. 2009 Sep 12. 374(9693):868. [QxMD MEDLINE Link].
Zhang WC, Lü SL, Liu DY, Liu PW, Yonmochi S, Wang XJ, et al. [Distribution Characteristics of Heavy Metals in the Street Dusts in Xuanwei and Their Health Risk Assessment]. Huan Jing Ke Xue. 2015 May. 36 (5):1810-7. [QxMD MEDLINE Link].
Hornung RW, Lanphear BP, Dietrich KN. Age of greatest susceptibility to childhood lead exposure: a new statistical approach. Environ Health Perspect. 2009 Aug. 117(8):1309-12. [QxMD MEDLINE Link]. [Full Text].
Adams J, Howsmon DP, Kruger U, Geis E, Gehn E, Fimbres V, et al. Significant Association of Urinary Toxic Metals and Autism-Related Symptoms-A Nonlinear Statistical Analysis with Cross Validation. PLoS One. 2017. 12 (1):e0169526. [QxMD MEDLINE Link]. [Full Text].
Prozialeck WC, Edwards JR, Nebert DW, et al. The vascular system as a target of metal toxicity. Toxicol Sci. 2008 Apr. 102(2):207-18. [QxMD MEDLINE Link].
[Guideline] Caravati EM, Erdman AR, Christianson G, Nelson LS, Woolf AD, Booze LL, et al. Elemental mercury exposure: an evidence-based consensus guideline for out-of-hospital management. Clin Toxicol (Phila). 2008 Jan. 46(1):1-21. [QxMD MEDLINE Link]. [Full Text].
[Guideline] Manoguerra AS, Erdman AR, Booze LL, Christianson G, Wax PM, Scharman EJ, et al. Iron ingestion: an evidence-based consensus guideline for out-of-hospital management. Clin Toxicol (Phila). 2005. 43(6):553-70. [QxMD MEDLINE Link]. [Full Text].
Johnson-Arbor K, Schultz B. Effective Decontamination and Remediation After Elemental Mercury Exposure: A Case Report in the United States. J Prev Med Public Health. 2021 Sep. 54 (5):376-379. [QxMD MEDLINE Link]. [Full Text].

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Table. Typical Presentation of the Most Commonly Encountered Metals and Their Treatment

Table. Typical Presentation of the Most Commonly Encountered Metals and Their Treatment

Metal	Acute	Chronic	Toxic Concentration	Treatment
Arsenic	Nausea, vomiting, "rice-water" diarrhea, encephalopathy, MODS, LoQTS, painful neuropathy	Diabetes, hypopigmentation/ hyperkeratosis, cancer: lung, bladder, skin, encephalopathy	24-h urine: ≥50 µg/L urine, or 100 µg/g creatinine	BAL (acute, symptomatic) DMSA (succimer) DMPS (Europe)
Bismuth	Acute kidney injury; acute tubular necrosis	Diffuse myoclonic encephalopathy	No clear reference standard	*
Cadmium	Pneumonitis (oxide fumes)	Proteinuria, lung cancer, osteomalacia	Proteinuria and/or ≥15 µg/ g creatinine	*
Chromium	GI hemorrhage, hemolysis, acute renal failure (Cr⁶⁺ ingestion)	Pulmonary fibrosis, lung cancer (inhalation)	No clear reference standard	NAC (experimental)
Cobalt	Beer drinker’s (dilated) cardiomyopathy	Pneumoconiosis (inhaled); goiter	Normal excretion: 0.1-1.2 µg/L (serum) 0.1-2.2 µg/L (urine)	NAC CaNa₂ EDTA
Copper	Blue vomitus, GI irritation/ hemorrhage, hemolysis, MODS (ingested); MFF (inhaled)	vineyard sprayer’s lung (inhaled); Wilson disease (hepatic and basal ganglia degeneration)	Normal excretion: 25 µg/24 h (urine)	BAL D-Penicillamine DMSA (succimer)
Iron	Vomiting, GI hemorrhage, cardiac depression, metabolic acidosis	Hepatic cirrhosis	Nontoxic: < 300 µg/dL Severe: >500 µg/dL	Deferoxamine
Lead	Nausea, vomiting, encephalopathy (headache, seizures, ataxia, obtundation)	Encephalopathy, anemia, abdominal pain, nephropathy, foot-drop/ wrist-drop	Pediatric: symptoms or [Pb] ≥45 µ/dL (blood); Adult: symptoms or [Pb] ≥70 µ/dL	BAL CaNa₂ EDTA DMSA (succimer)
Manganese	MFF (inhaled)	Parkinson-like syndrome, respiratory, neuropsychiatric	No clear reference standard	*
Mercury	Elemental (inhaled): fever, vomiting, diarrhea, ALI; Inorganic salts (ingestion): caustic gastroenteritis	Nausea, metallic taste, gingivo-stomatitis, tremor, neurasthenia, nephrotic syndrome; hypersensitivity (Pink disease)	Background exposure "normal" limits: 10 µg/L (whole blood); 20 µg/L (24-h urine)	BAL DMSA (succimer) DMPS (Europe)
Nickel	Dermatitis; nickel carbonyl: myocarditis, ALI, encephalopathy	Occupational (inhaled): pulmonary fibrosis, reduced sperm count, nasopharyngeal tumors	Excessive exposure: ≥8 µg/L (blood) Severe poisoning: ≥500 µg/L (8-h urine)	*
Selenium	Caustic burns, pneumonitis, hypotension	Brittle hair and nails, red skin, paresthesia, hemiplegia	Mild toxicity: [Se] >1 mg/L (serum); Serious: >2 mg/L	*
Silver	Very high doses: hemorrhage, bone marrow suppression, pulmonary edema, hepatorenal necrosis	Argyria: blue-grey discoloration of skin, nails, mucosae	Asymptomatic workers have mean [Ag] of 11 µg/L (serum) and 2.6 µg/L (spot urine)	Selenium, vitamin E (experimental)
Thallium	Early: Vomiting, diarrhea, painful neuropathy, coma, autonomic instability, MODS Late: Alopecia, Mees lines, residual neurologic symptoms	Alopecia, neuropathy	Toxic: >3 µg/L (blood)	MDAC Prussian blue
Zinc	MFF (oxide fumes); vomiting, diarrhea, abdominal pain (ingestion)	Copper deficiency: anemia, neurologic degeneration, osteoporosis	Normal range: 0.6-1.1 mg/L (plasma) 10-14 mg/L (red cells)	*
*No accepted chelation regimen; contact a medical toxicologist regarding treatment plan. MODS, multi-organ dysfunction syndrome; LoQTS, long QT syndrome; ALI, acute lung injury; ATN, acute tubular necrosis; ARF, acute renal failure; DMPS, 2,3-dimercapto-1-propane-sulfonic acid; CaNa₂ EDTA, edetate calcium disodium; MDAC, multi-dose activated charcoal; NAC, N-acetylcysteine; DMSA (succimer), dimercaptosuccinic acid.

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Author

Adefris Adal, MD, MS Clinical Assistant Instructor, Resident Physician, Department of Emergency Medicine, Kings County Hospital Center, State University of New York Downstate Medical Center

Disclosure: Nothing to disclose.

Coauthor(s)

Sage W Wiener, MD Assistant Professor, Department of Emergency Medicine, State University of New York Downstate Medical Center; Director of Medical Toxicology, Department of Emergency Medicine, Kings County Hospital Center

Sage W Wiener, MD is a member of the following medical societies: American Academy of Clinical Toxicology, American Academy of Emergency Medicine, American College of Medical Toxicology, Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.

Specialty Editor Board

John T VanDeVoort, PharmD Regional Director of Pharmacy, Sacred Heart and St Joseph's Hospitals

John T VanDeVoort, PharmD is a member of the following medical societies: American Society of Health-System Pharmacists

Disclosure: Nothing to disclose.

John G Benitez, MD, MPH Associate Professor, Department of Medicine, Medical Toxicology, Vanderbilt University Medical Center; Managing Director, Tennessee Poison Center

John G Benitez, MD, MPH is a member of the following medical societies: American Academy of Clinical Toxicology, American Academy of Emergency Medicine, American College of Medical Toxicology, American College of Preventive Medicine, Undersea and Hyperbaric Medical Society, Wilderness Medical Society, American College of Occupational and Environmental Medicine

Disclosure: Nothing to disclose.

Chief Editor

Additional Contributors

Mark Louden, MD Assistant Professor of Clinical Medicine, Division of Emergency Medicine, Department of Medicine, University of Miami, Leonard M Miller School of Medicine

Mark Louden, MD is a member of the following medical societies: American College of Emergency Physicians

Disclosure: Nothing to disclose.

Acknowledgements

Richard H Sinert, DO Associate Professor of Emergency Medicine, Clinical Assistant Professor of Medicine, Research Director, State University of New York College of Medicine; Consulting Staff, Department of Emergency Medicine, Kings County Hospital Center

Richard H Sinert, DO is a member of the following medical societies: American College of Physicians and Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.

Samara Soghoian, MD, MA Clinical Assistant Professor of Emergency Medicine, New York University School of Medicine, Bellevue Hospital Center

Samara Soghoian, MD, MA is a member of the following medical societies: American Academy of Clinical Toxicology, American College of Medical Toxicology, and Society for Academic Emergency Medicine

Disclosure: Nothing to disclose.