Cadmium Toxicity

Abhishek Jha

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

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

EFFECTS OF POISONING:

SYMPTOMS

• Food poisoning (ingestion)

• Bronchitis (inhalation)

• Interstitial pneumonitis (inhalation)

• Pulmonary edema (inhalation)

• MEDICAL CONDITIONS

• Osteoporosis

• Osteomalacia

• Hyperuricemia

• Hypophosphatemia

• Itai-itai disease

• Renal failure

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

• 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

Health Effect of Cadmium

• The International Agency for Research on Cancer (IARC) of the World 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.

• 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)

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 damag

e

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

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)

Metabolism, storage and excretion of cadmium in human body

Journal of Occupational Medicine and Toxicology 2006

Safety reference value of cadmium

• The Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives (JECFA)

• established a provisional tolerable monthly intake (PTMI) of 25 mcg/kg bw to cadmium in 2010

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

DIAGNOSIS

• DIRECT EVALUATION24 hour urine cadmium – reflects exposure over time Blood cadmium-estimated

• INDIRECT EVALUATION Urinary ß 2 -microglobulin – evaluate urine levels > 300 g/g creatinine Urinary retinol-binding protein(RBP)UrinaryMetallothionein (MT)

• Critical levels: blood cadmium: 10 micrograms/l Urinary cadmium: 10 micrograms/g creatinine Urinary beta 2-microglobulin: 2000 micrograms/g creatinine Urinary retinol-binding protein: 200 micrograms/g creatinine

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 like Vitamin C, 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

SMOKING IS INJURIOUS TO HEALTH…..STOP SMOKING!!!:

Thank You