What two statements below show beneficial impacts of microbes in the environment?

The impacts of presence of microbes in environment which results beneficial to the environment are the nitrogen fixation process carried out by the nitrogen fixing bacteria usually cyanobacteria.

The cellulose degrading microbes which is observed to be found in the rumen of the ruminant animals.

Also, regeneration of the nutrients in soil and water is done by micro-organisms.

exposure to hazardous carcinogens and toxic substances can cause breathing problems, such as copd and various types of cancer. it also increases the risk of heart attacks and strokes and has serious (but no less unattractive) side effects, such as aging, yellow teeth, a terrible smell and damage to the vocal cords.