[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Conditions](https://durgical.com/en/conditions/) › Lead poisoning [Conditions](https://durgical.com/en/conditions/) · [Metabolism: heme, bilirubin and iron](https://durgical.com/en/conditions/) # Lead poisoning Lead exposure that harms children's brains, nerves, kidneys and blood; there is no safe level of lead. Updated 2026-11-01 ## Structures involved Tap one to see what it is and open it in 3D. - [White matter](https://durgical.com/en/anatomy/white-matter-of-telencephalon/) - [Kidneys](https://durgical.com/en/anatomy/kidney/) - [Hippocampus](https://durgical.com/en/anatomy/hippocampus/) - [Radial nerve](https://durgical.com/en/anatomy/radial-nerve/) - [Gums (gingiva)](https://durgical.com/en/anatomy/gums/) - [Stomach](https://durgical.com/en/anatomy/stomach/) - [Transverse colon](https://durgical.com/en/anatomy/transverse-colon/) ## In biochemistry - [Heme synthesis: Step 2 · ALA dehydratase (porphobilinogen synthase)](https://durgical.com/en/biochemistry/pathways/heme-synthesis/#paso-2) - [ALA dehydratase](https://durgical.com/en/biochemistry/enzymes/ala-dehydratase/) - [Ferrochelatase](https://durgical.com/en/biochemistry/enzymes/ferrochelatase/) - [Protoporphyrin IX](https://durgical.com/en/biochemistry/molecules/protoporphyrin-ix/) - [Porphobilinogen](https://durgical.com/en/biochemistry/molecules/porphobilinogen/) - [δ-Aminolevulinic acid (ALA)](https://durgical.com/en/biochemistry/molecules/aminolevulinic-acid/) ## Why it happens - [Heavy metals: lead, mercury, arsenic and cadmium](https://durgical.com/en/general-pathology/heavy-metals-lead-mercury-arsenic-and-cadmium/) ## What it is Acute or chronic poisoning with inorganic lead, which inhibits sulfhydryl enzymes, including ALA dehydratase and ferrochelatase of heme synthesis. ## Who gets it WHO attributes millions of deaths a year to lead, mostly cardiovascular, and much of the preventable intellectual disability in children. In Colombia and Latin America important sources are informal battery recycling, mining, old paint and lead-glazed pottery. ## Causes - Inhaling lead dust or fumes (smelters, batteries) - Ingesting flaking paint, contaminated soil or food from glazed pottery - Retained bullets near joints ## Risk factors - Young children (hand-to-mouth behaviour, higher absorption) - Work in battery recycling, welding, painting or mining - Pregnancy (bone lead is mobilised) - Iron and calcium deficiency ## Pathophysiology Lead binds sulfhydryl groups and displaces zinc and calcium. It inhibits ALA dehydratase (ALA, a neurotoxin, rises) and ferrochelatase (zinc protoporphyrin forms), causing microcytic anemia. It inhibits pyrimidine 5'-nucleotidase (basophilic stippling), damages the renal tubule and disturbs brain synapses and development. About 90 % of adult body lead is stored in bone. ## Symptoms and signs - In children: developmental delay, learning and behaviour problems, irritability - Colicky abdominal pain and constipation (lead colic) - Wrist extensor weakness (wrist drop) - Fatigue and pallor from anemia - Blue-grey line along the gum margin (Burton line) - Headache, joint pain, hypertension ## Red flags - Persistent vomiting, drowsiness, seizures or coma (lead encephalopathy) - A child with pica and anemia ## Diagnosis **Clinical** Occupational, household or environmental exposure with digestive or neurological symptoms or anemia; in children, screening in high-risk areas. **Tests** Venous blood lead (the reference test); raised red-cell zinc protoporphyrin; blood count with microcytic anemia and basophilic stippling; high urine ALA with normal porphobilinogen; [kidney](https://durgical.com/en/anatomy/kidney/) function. **Imaging** Knee X-ray in children (dense metaphyseal lines) and abdominal X-ray to look for swallowed paint chips. ## Treatment **Conservative** Identifying and removing the source of exposure; the most important measure **Medical** Chelation (oral succimer, calcium disodium edetate, dimercaprol) according to lead level and symptoms **Acute** Encephalopathy: intensive care, control of seizures and raised intracranial pressure, and parenteral chelation **Medical** Correcting iron and calcium deficiencies, which increase lead absorption **Surgical** Removal of lead bullets near joints when they cause poisoning ## Drugs for this condition - [Dimercaprol](https://durgical.com/en/pharmacology/dimercaprol/) - [Sodium calcium edetate](https://durgical.com/en/pharmacology/sodium-calcium-edetate/) - [Succimer](https://durgical.com/en/pharmacology/succimer/) ## Complications - Permanent cognitive impairment in children - Chronic nephropathy and hypertension - Lead (saturnine) gout - Miscarriage and premature birth ## Prevention - Removing lead from paint, petrol and pottery - Regulating battery recycling and occupational protection - Screening exposed children and pregnant women ## Test yourself Think of the answer, then tap the question to see it. ## Which two heme-synthesis enzymes does lead inhibit? ALA dehydratase and ferrochelatase. ## Which blood-smear finding is typical of lead poisoning? Basophilic stippling, from inhibition of pyrimidine 5'-nucleotidase (leftover RNA). ## Which test confirms lead poisoning? Venous blood lead level. ## Where is most lead stored in an adult? In bone (about 90 %), from which it is released in pregnancy or osteoporosis. [Add to my cards (4)](https://durgical.app/estudiar/?add=/en/conditions/lead-poisoning/) ## Related conditions - [Acute intermittent porphyria](https://durgical.com/en/conditions/acute-intermittent-porphyria/) - [Iron deficiency anaemia](https://durgical.com/en/conditions/iron-deficiency-anaemia/) Educational information, not medical advice. For any symptom, see a health professional. Sources: [Lead poisoning](https://www.who.int/news-room/fact-sheets/detail/lead-poisoning-and-health) (World Health Organization, 2026); [Lead poisoning: MedlinePlus Medical Encyclopedia](https://medlineplus.gov/ency/article/002473.htm) (MedlinePlus, US National Library of Medicine, 2026); [ALAD gene: MedlinePlus Genetics](https://medlineplus.gov/genetics/gene/alad/) (MedlinePlus, US National Library of Medicine, 2026); Textbook of Biochemistry for Medical Students, 6th ed. (Jaypee Brothers Medical Publishers (Vasudevan DM, Sreekumari S, Vaidyanathan K), 2011). [← All conditions](https://durgical.com/en/conditions/) ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/conditions/lead-poisoning/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/conditions/lead-poisoning/