MESOTHELIOMA

carcinogen is a cancer-causing substance.

carcinogen is produced by

1.fungus aspergillus ,which produces aflatoxin B1, grows on stored grains,peanut butter,nuts etc.
2.cooking protein-rich foods at high temperatures
3.cigarette smoke
4.some plants produce carcinogens to prevent animals from eating them.

carcinogens cause cancer by altering the cellular matabolism or by damaging the DNA.

when the cells are unable to detect this,they undergo programmed cell death(to protect the organism),but when the damage interferes with genes,which are responsible for cell death,cancer occur.

cells in skin,stomach,breast,intestinla lining are capable of rapid lining and hence sensitive to carcinogens.

classification

1.Group 1 - Known human carcinogen
when there is sufficient evidence of carcinogenicity in humans.

2.Group 2A - Probable human carcinogen
when there is limited evidence of carcinogenicity in humans and sufficient evidence of carcinogenicity in experimental animals

3.Group 2B - Possible human carcinogen
there is limited evidence of carcinogenicity in humans and less than sufficient evidence of carcinogenicity in experimental animals.
4.Class 3 - Not classifiable for human carcinogenicity
the evidence of carcinogenicity is inadequate in humans and inadequate or limited in experimental animals
5.Class 4 - Probably not carcinogenic to humans
there is evidence suggesting lack of carcinogenicity in humans and in experimental animals.