## How Much Radiation Does a Smoker’s Lung Absorb Yearly?
Radiation is all around us—in the air, the ground, even inside our bodies. But for smokers, there’s an extra source of radiation that most people don’t think about: radioactive particles in tobacco smoke. To understand how much radiation a smoker’s lungs absorb each year, we need to look at where this radiation comes from, how it gets into the lungs, and what that means for health.
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## Where Does the Radiation in Tobacco Come From?
Tobacco plants naturally absorb radioactive elements from soil and fertilizer. The main culprits are polonium-210 (Po-210) and lead-210 (Pb-210), both of which are products of uranium decay. These elements stick to tiny hairs on tobacco leaves and stay there even after processing. When tobacco burns in a cigarette, these radioactive particles become part of the smoke.
When you inhale cigarette smoke, these tiny radioactive particles settle deep inside your lungs—especially in sensitive areas where oxygen is absorbed into your blood. Over time, they build up and keep emitting radiation directly onto lung tissue.
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## How Much Radiation Are We Talking About?
Let’s break down the numbers:
**Natural Background Radiation:**
Everyone on Earth is exposed to natural background radiation—from cosmic rays, rocks like granite (which contain uranium), radon gas seeping from the ground, and even small amounts inside our bodies (like potassium-40). The average person gets about 2–3 millisieverts (mSv) per year just from living their daily life.
**Radiation From Smoking:**
Smokers get extra doses on top of this background level because their lungs are exposed directly to Po-210 and Pb-210 particles every time they inhale smoke.
A typical smoker who smokes one pack per day can receive an additional effective dose equivalent to about 0.006 mSv per year just from these internal emitters settling in their lungs. That might not sound like much compared to natural background levels—but here’s why it matters:
The real concern isn’t just the total yearly dose; it’s where that dose goes. Natural background radiation spreads out over your whole body or comes mostly as external exposure (like sunlight). But with smoking-related radioactivity, almost all of it concentrates right where you breathe: deep inside your lung tissue.
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## What Happens Inside a Smoker’s Lungs?
When Po-210 decays inside your lung cells
