Secondhand smoke (SHS), also known as environmental tobacco smoke, has been widely studied for its detrimental health effects, particularly its association with lung cancer in non-smokers. Despite growing public health awareness and legislative measures to reduce SHS exposure, global prevalence remains significant, especially in low- and middle-income countries. This paper critically examines the relationship between secondhand smoke and lung cancer through the lens of Bradford Hill’s nine criteria for establishing causality: strength, consistency, specificity, temporality, biological gradient, plausibility, coherence, experiment, and analogy.
Findings from major epidemiological studies and meta-analyses show that exposure to SHS significantly increases lung cancer risk among non-smokers. The biological mechanisms—such as the presence of carcinogens like benzene and formaldehyde in SHS—offer strong plausibility. Moreover, temporal relationships are evident in cohort studies, while experimental and interventional data from smoke-free laws reveal reductions in SHS exposure and related disease burdens. Although challenges exist in measuring long-term exposure levels, the cumulative evidence supports a strong causal relationship. The application of Hill’s criteria thus reinforces the need for stricter enforcement of public smoking bans and targeted education campaigns to protect vulnerable populations.
- Quote paper
- Kingsley Adimabua (Author), 2025, Evaluating the Causal Link Between Secondhand Smoke Exposure and Lung Cancer. An Application of Bradford Hill’s Criteria, Munich, GRIN Verlag, https://www.grin.com/document/1597572
