30 yr old f. was exposed to a lot of second-hand smoke at my workplace for the past year, ~ 7 hrs/day. quit the job. how long will it take for my lung cancer risk to get back to what it was before this job? i am healthy otherwise. i am very worried?

https://www.hopkinsmedicine.org/health/conditions-and-diseases/lung-cancer/former-smoker-whats-your-risk-for-lung-cancer https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2515267/ The cancer risk from 2nd hand smoke is greater if less than 25 years when exposed and had several years exposure. Lung cancer risk for smokers is decreased by 90% if younger than 40 at time of quitting, Your risk may low

Any damage form second hand smoke will dissipate over time. You can reduce your risk of cancer by adopting healthy habits: Eat a mostly vegetarian diet, avoid alcohol, tobacco and street drugs, avoid excessive to sun, get HPV vaccine, exercise 30 minutes each day, drink enough water so your urine is mostly colorless.