Hair cadmium (Cd) levels provide an indication of mild to moderate exposure to the nephrotoxic metal. Very high exposure and assimilation of Cd destroys the hair follicle. Cd is a toxic heavy metal that has no metabolic function in the body. Moderately high Cd exposure may be associated with hypertension, while very severe Cd toxicity may cause hypotension. Cd adversely affects the kidneys, lungs, testes, arterial walls, and bones and interferes with many enzymatic reactions. Chronic Cd excess can lead to microcytic, hypochromic anemia and proteinuria with excretion of beta-2-microglobin, and functional zinc deficiency. Cd excess is also commonly associated with fatigue, hypertension, kidney disease, weight loss, osteomalacia, and lumbar pain. Occupationally, inhalation of Cd is the primary route of exposure. Otherwise the most significant source of exposure is due to contaminated food and water. Cd occurs at relatively high levels in human biosolids that are used as fertilizer. Cd absorption is reduced by zinc, calcium, and selenium. Oral absorption of Cd is generally higher in females than in males due to differences in iron stores. Cd is found in varying amounts in foods, from .04 μg/g for some fruits to 3-5 μg/g in some oysters and anchovies. Refined carbohydrates have very little zinc in relation to Cd. Cigarette smoking significantly increases Cd intake. Other sources of Cd include drinking water, fungicides, rubber products (tires), welding rods, and silver solders, and interestingly, old metal refrigerator shelves that have been utilized as grills for outdoor cooking. Cadmium toxicity is common among welders and construction workers (cement dust).
Urinary cadmium (Cd) provides an indication of recent or ongoing exposure to the toxic metal, and endogenous detoxification to a lesser extent. Most of absorbed Cd is retained in the liver and kidneys for many years. A small portion of assimilated Cd body leaves slowly in urine and bile/feces. Absorption, systemic transport and cellular uptake of Cd are mediated by metal transporters that the body uses for the essential elements iron, zinc and calcium. For nonsmokers the primary source of Cd exposure is food. Cd is found in varying amounts in foods; from very low for fruits to high in some shellfish (oysters, anchovies) and organ meats. Root vegetables tend to have higher Cd content than other vegetables. Refined carbohydrates have very little zinc in relation to the Cd; zinc competes with Cd for absorption from the gut. Tobacco leaves accumulate high levels of cadmium, and Cd absorption across the lungs is very efficient. Urban particulate air pollution/dust (diesel smoke, tire wear) is a significant source of Cd exposure. Other sources of Cd include: human biosolids, tires, pigments and paints, plastics, and batteries (Ni-Cd). The majority of Cd-containing batteries are improperly disposed of and contribute to environmental exposure. Excessive exposure to Cd may be symptomatically associated with fatigue, weight loss, osteomalacia, and lumbar pain. Chronic exposure to Cd may adversely affect the kidneys, lungs, testes, arterial walls, and bones. Chronic Cd excess may lead to hypertension, coronary and peripheral vascular disease, macular degeneration, kidney disease, obesity-independent diabetes, and microcytic, hypochromic anemia and functional zinc deficiency. Cd is known to damage the kidneys, especially the proximal tubular cells that actively reabsorb Cd along with zinc, glucose and amino acids. Cd is pro-inflammatory and pro-oxidative. Urinary or serum beta-2-microglobulin is considered to be the best test for assessment of Cd-associated functional damage to the kidneys. Urine amino acid wasting may also be considered. Chelation may acutely increase urinary excretion of Cd.
Toxic Elements
Toxic metals
The principal organs most vulnerable to cadmium toxicity are kidney and lung. Environmental cadmium exposure is associated with renal tubular damage and high blood pressure. Cadmium toxicity impacts the kidney, where damage to proximal tubules has been described. Also, cadmium compounds are classified as carcinogenic to humans. Associated conditions include: → Renal: hypertension, kidney failure → Neurological: loss of coordination, numbness of limbs, loss of hearing Whole blood cadmium is indicative of recent exposure, and is therefore not reflective of total-body burden. Normal concentration of whole blood cadmium is up to 1 μg/L for nonsmokers, and up to 4 μg/L for smokers. Whole blood levels of 10 μg/L have been associated with renal dysfunction. Associated Symptoms and Diseases: Femoral pain, lumbago, osteopenia, renal dysfunction, hypertension, vascular disease Sources: Industry, spray paint, tobacco smoke, car emissions, plants grown in cadmium-rich soil Protective Measures: Zinc, iron, antioxidants Chelating Agents: EDTA; DMSA and NAC (experimental)
Toxic Elements
Cadmium (Hair) – What Your Lab Results Mean Cadmium is a heavy metal that can accumulate in the body over time and may cause harmful effects at elevated levels. When measured through hair analysis, cadmium reflects long-term exposure to this toxic element, offering insight into environmental or occupational sources of contamination. What is Cadmium? Cadmium is a naturally occurring metal found in the earth’s crust. It’s commonly used in: Batteries (especially nickel-cadmium batteries) Pigments and coatings Cigarette smoke Industrial processes like metal plating, mining, and smelting Humans can absorb cadmium through inhalation, contaminated food, water, or tobacco smoke. Why Test Cadmium in Hair? Hair tissue mineral analysis (HTMA) offers a non-invasive, long-term record of heavy metal exposure over several months. Unlike blood or urine tests, which reflect more recent exposure, hair testing is ideal for identifying chronic cadmium accumulation. What Do Cadmium Hair Levels Indicate? Level Interpretation Low Typically no concern. However, low levels in the presence of high body burden (stored cadmium) may occur if the body is not excreting it properly. Normal Suggests no significant long-term exposure. High Indicates chronic cadmium exposure or poor detoxification. May warrant further investigation and clinical follow-up. Potential Health Effects of High Cadmium Chronic cadmium exposure has been linked to: Kidney damage (particularly affecting tubule function) Bone demineralization (osteoporosis, fractures) Respiratory problems (if inhaled) Hypertension Increased cancer risk (especially lung and prostate) Cadmium is classified as a Group 1 carcinogen by the International Agency for Research on Cancer (IARC). Who’s at Risk for High Cadmium? Smokers (tobacco plants absorb cadmium from soil) People with occupational exposure (welding, metal work, battery manufacturing) Residents near industrial areas People consuming contaminated shellfish, grains, or vegetables How to Reduce Cadmium Exposure Stop smoking and avoid secondhand smoke. Eat a balanced diet rich in zinc, iron, and calcium, which can reduce cadmium absorption. Filter drinking water if contamination is suspected. Avoid using old ceramic or metal cookware with unknown glazes or coatings. Consider testing household dust or soil if living near industrial sites. Next Steps After an Elevated Result If your cadmium levels are high: Identify the source of exposure. Consider additional testing (blood, urine, or kidney function tests). Work with a healthcare provider to develop a detoxification or chelation plan, if necessary. Monitor levels regularly with follow-up hair or other lab testing. References & Further Reading Agency for Toxic Substances and Disease Registry (ATSDR): Cadmium [L] World Health Organization (WHO): Cadmium in Drinking Water [L] IARC Monographs on the Evaluation of Carcinogenic Risks to Humans [L]
Toxic Elements
Whole blood cadmium is within the normal reference range, which is a favorable finding indicating low recent exposure to this toxic metal. However, if cadmium levels are at the high end of the normal range, it is important to also measure urinary cadmium, which better reflects long-term body burden. Cadmium bioaccumulates in the body over time. At birth, cadmium levels are minimal, but by age 30, accumulated levels may reach a point where they begin to negatively affect health. Cadmium has a biological half-life of 15–30 years in the kidneys, making urine testing the preferred method for assessing cumulative, lifetime exposure. Cadmium is a non-essential, highly toxic element. It is: A known kidney toxin A neurotoxin affecting peripheral nerves An estrogen mimic that can disrupt hormonal balance A Group 1 carcinogen (classified by the IARC) Elevated cadmium levels have been associated with increased risk of several cancers, including: Lung Prostate Breast Endometrial Testicular Kidney Bladder Pancreatic Gallbladder Sources of Cadmium Exposure Cadmium enters the human body primarily through: Diet: vegetables, grains, root crops, seafood, and organ meats, all of which can absorb cadmium from contaminated soil. Tobacco smoke: Smokers typically have twice the urinary cadmium levels of non-smokers due to high lung absorption (up to 50%). Environmental and occupational sources: mining, smelting, manufacturing of nickel-cadmium batteries, artisan glass production, use of phosphate fertilizers and pesticides, improper waste disposal, and vehicle exhaust. Reducing cadmium exposure through dietary awareness, avoiding tobacco, and minimizing occupational risk is key to long-term health and preventing cadmium-induced toxicity.
Toxic Elements
Exposure to inorganic cadmium fumes in industrial settings can cause various health issues such as fatigue, coughing, chest pain, a burning sensation in the throat, and kidney damage. People with cadmium-induced kidney problems generally have a poor prognosis, with urinary β-microglobulin and urinary protein being critical indicators. Inhalation of cadmium fumes can result in pneumonia with acute exposure and emphysema with prolonged exposure. Cadmium poisoning is mainly linked to exposure to cadmium fumes and inorganic cadmium salts, which are common in certain industrial environments. Cadmium and its compounds are widely used in industry, particularly in alloys and metal plating. Inorganic cadmium fumes or dust are typically produced during activities such as heating, welding, and grinding cadmium-containing metals. For the general population, cadmium exposure mainly comes from dietary sources, with an average intake ranging from 2 to 200 μg per day, and is rarely a cause of overexposure. Cadmium also exists in organic forms in food, water, and air, with daily intake typically between 2 and 200 μg. While this form can be toxic, overexposure to organic cadmium usually results from specific environmental pollution incidents. Whole blood testing is recommended for assessing acute or recent cadmium exposure. Biological Exposure Indices (BEI®) serve as guidelines for evaluating occupational exposure. BEIs reflect biological levels of chemicals that align with the threshold limit values (TLV®) for airborne concentrations. TLVs indicate the maximum amount of a substance to which most workers can be repeatedly exposed without adverse health effects.