Cadmium is a toxic heavy metal that occurs naturally and is used industrially. It accumulates in the environment and organisms. Exposure can cause acute flu-like symptoms and long-term effects like lung and kidney damage. Cadmium is classified as carcinogenic to humans. It interferes with enzyme function and displaces other metals. Diagnosis involves measuring cadmium levels in blood and urine. Treatment focuses on reducing further exposure and chelation therapy. Smoking is a major source of cadmium exposure that should be avoided.
2. What is it ?
• Toxic soft whitish metal occurs naturally in soil, commonly found in industrial
workplace. Encountered with earth’s crust combined with chlorine(CdCl2), oxygen
(CdO), Sulphur (CdS). Exists as small particles in air, result of smelting, soldering or
other high temp. industrial processes or by product of smelting of zinc, lead,
copper ores.
• Used extensively in electroplating, rechargeable batteries, commercial food
processing as a fertilizer, paint pigments, pottery glazes and plastics and as a
neutron absorbent in nuclear reactors. It is cheap, shiny, strong and malleable at
low temp.
Cadmium does not break down in the environment
3. Cadmium Poisoning
• Caused by excessive exposure to cadmium
• No constructive purpose in the human body.
• Extremely toxic even in low concentrations and will bioaccumulation in
organisms and ecosystems due to low permissible exposure limit so
overexposure occur where trace quantities found.
• The McDonalds Shrek Glasses are contaminated with Cadmium
7. Source of Exposure
• Tobacco smoke (a one pack a day smoker absorbs roughly 5 to 10 times the
amount absorbed from the average daily diet)
• Cadmium a component of chuifong tokwan , sold illegally as a miracle herb in
china
• Low levels are found in grains, cereals, leafy vegetables, and other basic
foodstuffs
8. • Build up of cadmium levels in water, air, soil has been occurring in industrial areas.
Environmental exposure has been problematic in japan where many people
consumed rice that was grown in cadmium contaminated irrigation water which
caused itai-itai disease.
• In May 2013, it was reported that certain rice and rice products collected by
Guangdong authorities, containing cadmium at levels which did not comply with
the Mainland standard.
• Mainland GB standard for cadmium in rice is ≦ 0.2 mg/kg.
• Occurrence in Food -plants, animals, fish and shellfish take up cadmium when it is
in their growth environment (e.g. soil, air, water, etc.) . Use of cadmium-containing
fertilizers and feeding stuff.
Cadmium can go up the food chain when contaminated crops and plants are
ingested by animals
9.
10. Health Effect of Cadmium
• The International Agency for Research on Cancer (IARC) of theWorld Health
Organization considered that
sufficient evidence of carcinogenicity of cadmium and cadmium compounds in
humans due to occupational exposure through inhalation, and classified them as
“carcinogenic to human” (Group 1 agents)
• However, acute exposure may cause flu like symptoms including fever, chills, chest
pain, dizziness and muscle ache sometimes referred to as “the cadmium blues”.
More severe exposure can cause tracheo-bronchitis, pneumonitis and pulmonary
edema.
• Primary effect on lungs and kidney
Lung, Emphysema, Kidney, Calcium metabolism, Possible lung carcinogen.
Secondary effects on skeletal system.
11. • Binds to sulfhydryl groups, displacing other metals from metalloenzymes,
disrupting those enzymes.
• competing with calcium for binding sites (calmodulin)
• In kidney- Free Cd binds to kidney glomerulus
- Proximal tubule dysfunction
• In lung- Edema and Emphysema by killing lung macrophages
• In skeletal - Osteoporosis and osteomalacia (pseudo fractures)
12. Inhibition of DNA repair
Cell damage
Oxidative stress
Enhancement of DNA
damage
Decrease of Antioxidants
Activation of cellular
signals
Inhibition of DNA
Methylation
E-cadherin dysfunction
DNA
damage
Induction of Proto-
Oncogenes
Disruption Cell Adhesion
Induction of Apoptosis
Gene
Mutation
Promotion
of
proliferation
Malignant
Cancer
Preneoplastic
lesion
Cd+
2
A Model: Major mechanism involved in Cd+2 Carcinogenesis
13. Cadmium epidemics/case studies
• Japan (1950s) “Itai-Itai” is Japanese for “ouch-ouch”-refers to bone pain related to calcium
loss
• Renal failure,Anemia, severe muscle pain
• River polluted with waste from factory, water used on rice fields
for many years
• Rice accumulated high level of Cd Community was poor (and therefore malnourished with
respect to calcium)
14. Metabolism, storage and excretion of cadmium in
human body
Journal of Occupational Medicine andToxicology 2006
15. Safety reference value of cadmium
• The Joint Food and Agriculture Organization/World Health Organization
Expert Committee on FoodAdditives (JECFA)
• established a provisional tolerable monthly intake (PTMI) of 25 mcg/kg bw
to cadmium in 2010
16. Dietary exposure to cadmium
• A risk assessment on dietary exposure to cadmium using the total diet study
(TDS) methodology was conducted
• The results indicated that the general population
was unlikely to experience major undesirable
health effects of cadmium from dietary exposure
18. TREATMENT
• Elements like calcium and selenium are shown to have protective effect against cadmium-
induced toxicity
• Adequate levels of zinc in the body helps to displace cadmium from the tissues
• Potent antioxidants likeVitaminC, Glutathione, methionine, glycine, cysteine has great
protective efficiency.
• Smoking should be avoided and do check your house products for compounds which
contain cadmium
• Chelation therapy