Overview

• A Thorax paper using Tasmanian Longitudinal Health Study data reports that paternal prepubertal exposure to secondhand smoke is associated with impaired lung-function trajectories in their children from childhood to middle age.
• Parental passive smoke exposure in childhood was linked to a 56% higher odds that offspring would have below-average FEV1, with a doubled risk of deteriorated pulmonary trajectories and early rapid decline in FEV1/FVC.
• Risk increased further when both generations were exposed in childhood, with the probability of below-average FEV1 in offspring doubling, indicating a cumulative intergenerational effect.
• The analysis draws on a cohort of 8,022 people born in 1961 with lung-function testing at six life stages, including an analysis of 890 father–child pairs and retrospective reports of ancestral smoke exposure.
• Authors and independent experts stress that the study is observational with self-reported exposures, propose epigenetic pathways as a possible explanation, and highlight implications for policies to reduce children’s exposure to tobacco smoke.