What does chronic exposure to tar in cigarettes primarily cause?

Chronic exposure to tar in cigarettes primarily causes cellular mutations. Tar, a byproduct of burning tobacco, contains numerous carcinogenic (cancer-causing) chemicals that can lead to changes in the DNA within cells. Over time, these mutations can accumulate, increasing the risk of developing various forms of cancer, particularly lung cancer.

Tar’s toxic components affect cellular structure and function, disrupting normal cellular processes and potentially leading to uncontrolled cell growth. This process is central to the development of cancerous tumors, as the normal signaling pathways that regulate cell division and apoptosis (programmed cell death) can be altered by these mutations. Therefore, the relationship between tar exposure and cellular mutations is a critical concern in understanding the health risks associated with smoking.