Many lung cancers are now in nonsmokers

Shifting patterns and statistics

• Several commenters stress that smoking rates have fallen sharply, so a larger share of lung cancers now occurs in nonsmokers even as overall incidence/mortality decline.
• Some argue the article’s framing (“many” cancers in nonsmokers) risks base‑rate fallacies unless absolute risks for smokers vs nonsmokers are shown.

Smoking, secondhand smoke, and other classical risks

• Multiple threads note that smoking is still the dominant cause; many smokers never get lung cancer but instead die of COPD or cardiovascular disease.
• Some wonder how much “family history” in studies is really secondhand smoke exposure.
• There is brief pushback against historic over‑attribution of lung cancer to smoking alone.

Outdoor pollution, cars, and urban form

• Large subthread blames fossil fuel emissions and traffic particulates (tires, brakes, road dust) for cancer and other health harms.
• Others counter that tailpipe emissions were orders of magnitude worse in the past; today’s engines and catalysts are much cleaner, though particulates remain.
• Commenters describe visible black dust near busy roads or parking lots and worry about tire/brake microplastics and toxic additives.
• Some argue car‑centric lifestyles and obesity in rich countries drive higher cancer and mortality than in “poor” bike‑ and walk‑oriented cities.

SUVs, safety, and individual vs social risk

• Heated exchange over large SUVs: feelings of safety vs actual increased danger to pedestrians, cyclists, and smaller cars.
• Some frame SUV choice as selfish but legal; others blame design standards (male‑sized crash dummies, poor accommodation for smaller drivers).
• A few liken vehicle size to an “arms race” in perceived safety and call for regulatory disincentives.

Radon: major theme, contested importance

• Many posts emphasize radon as a leading cause of lung cancer in nonsmokers and describe mitigation systems, monitoring, and regional variation.
• Others are skeptical of “second leading cause” claims, criticizing methodology and commercial fear‑marketing, and asking for clearer cost–benefit data.
• Debate over whether low‑dose radiation might have hormetic (beneficial) effects vs being straightforwardly harmful; no consensus.

Indoor air quality and modern housing

• Several suspect poor indoor air quality—tight envelopes, off‑gassing furniture, VOCs, plasticizers, combustion from gas stoves, mold—as a key driver of cancers and inflammation.
• Some note that radon, pollutants, and mold issues may worsen in tightly sealed, energy‑efficient homes without robust ventilation.

Cooking, ethnicity, and gender

• Commenters highlight high lung cancer rates in Asian and Asian‑American women mentioned in the article.
• Hypotheses include high‑temperature cooking (e.g., woks, oil aerosols), gas stoves, incense, and cleaning products, but evidence in the thread is anecdotal and labeled as speculative.
• There is disagreement over how common high‑heat wok cooking actually is among Asian‑American women.

Screening, diagnosis, and medicine’s focus

• Some argue physicians historically over‑focused on smoking, leading to misdiagnoses (e.g., asthma, anxiety, pneumonia) and late discovery in nonsmokers.
• Calls for broader, data‑driven lung cancer screening beyond heavy smokers, and for better diagnostic vigilance.

Vaping and future concerns

• Several expect vaping to drive a new wave of lung disease and possibly cancer, especially among youth with heavy, early nicotine exposure.
• Others note nicotine itself is not classically carcinogenic but may promote tumor growth and addiction that increases exposure to other toxins.

Science, uncertainty, and politics

• Many recognize genuine scientific uncertainty about causes in nonsmokers and stress the need for more research on environment, genetics, and interactions.
• Some complain tech audiences oversimplify complex epidemiology (“obviously cars” or “obviously radon”) and undervalue domain expertise.
• Others predict fierce political resistance to regulating whatever non‑smoking causes are ultimately confirmed (vehicles, chemicals, building standards, etc.).