naturally occuring mutagens

• • Occur at normal levels but increased exposure frequency→ mutations 
  • Biological: virus and bacteria
• • Non-biological: metals, such as mercury and cadmium 
• • Biological actions: end products of metabolism: many naturally occurring can be produced by fungi or plant/animal cells during metabolism
• • transposons: sections of DNA that spontaneously fragment and relocate or multiply within the genome→ When inserted into chromosomal DNA, they disrupt DNA functioning
• • Bio mutagens insert their own base sequences into DNA change the functioning and trigger cancers 
• Some bacteria cause inflammation where free radicals (reactive oxygen species) are producing→ DNA damage reducing the efficiency of DNA systems and increasing mutation e.g mycotoxins