Related by context. Frequent words. (Click for all words.) 73 secondhand smoke 62 passive smoking 59 cigarette smoking 57 nonsmokers 55 smoking 52 cigarette smoke 52 smokers 49 air pollution 49 UV exposure 49 caffeine intake 48 smoking bans 47 carcinogens 47 PBDEs 47 HPV infection 47 vitamin D deficiency 46 smokefree 46 radon 46 nonsmoking 46 Smoking 46 asbestos exposure 45 nonsmoker 45 nicotine 44 banning smoking 44 lung function 44 Tobacco Free 44 fine particulate matter 44 harmful effects 44 indoor tanning 44 psychological distress 44 phthalates 44 smoke 44 socioeconomic status 44 heart disease 44 salt intake 43 abdominal obesity 43 periodontal disease 43 diacetyl 43 vitamin D 43 smoker 43 calcium intake 43 particle pollution 43 sodium intake 43 mercury pollution 43 Clean Indoor 43 cardiovascular disease 43 diesel exhaust 42 COPD 42 gum disease 42 cognitive decline 42 lung cancer 42 acrylamide 42 pollutants 42 preterm birth 42 SIDS 42 Smoke Free 42 VOCs 41 mercury contamination 41 respiratory symptoms 41 preeclampsia 41 genetic variations 41 cigarette smokers 41 thimerosal 41 obesity 41 PFOA 41 hospitalizations 41 phthalate 41 asthma 41 smoking ban 41 UV radiation 41 index BMI 41 particulate matter 41 toxicity 40 cognitive impairment 40 depressive symptoms 40 epidemiological studies 40 oxidative stress 40 PAHs 40 risky behaviors 40 genetic variation 40 trans fats 40 ozone pollution 40 per deciliter 40 carcinogen 40 menthol cigarettes 40 physical inactivity 40 cortisol levels 40 tobacco 40 coronary heart 40 smokeless tobacco 40 vaccine preventable diseases 39 obese 39 harmful chemicals 39 metabolic syndrome 39 BPA 39 insulin resistance 39 Tobacco Control 39 prematurity 39 neural tube defects 39 HDL C 39 PFCs 39 childhood leukemia