Knowledge-practice decoupling in residential chemical indoor-air pollution: a cross-sectional survey in Lebanon

Residential chemical indoor-air pollution arises from combustion, smoking residues, fragranced products, cleaning chemistry, pesticides, building materials and ventilation behavior, yet household-level evidence from Lebanon remains limited. This study assessed knowledge, preventive attitudes, household practices and symptom recognition, with particular attention to whether knowledge translated into exposure-relevant behavior.

This secondary cross-sectional analysis used a non-probability convenience sample of 495 completed self-administered questionnaires collected between 8 November 2025 and 10 April 2026. Evidence-aligned scoring was used for knowledge and preventive attitudes, while practice items were separated into mitigation and source-frequency indices. Descriptive statistics, internal-consistency estimates, Wilson 95% confidence intervals, Spearman correlations, robust linear models and robust logistic models were used.

Respondents were predominantly young, female and university educated. Mean knowledge and preventive-attitude scores were 47.3 and 48.8 on 0-100 scales; the mean mitigation index was 66.3 and the mean source-frequency index was 58.4. Knowledge was moderately associated with preventive attitudes but only weakly associated with mitigation behavior. Higher preventive-attitude scores were associated with lower source-frequency, lower odds of regular indoor smoking and a higher mitigation-minus-source difference score. Symptom recognition was stronger for respiratory and neurological than for ocular, irritant and dermatological manifestations.

The findings indicate knowledge-practice decoupling within this sample: mitigation behaviors coexisted with frequent source-related activities, and knowledge alone did not explain household practice. Because the study used a non-probability, self-reported cross-sectional sample, results are sample-specific and do not establish national prevalence or causal effects. Source-specific risk communication and representative studies incorporating objective exposure measures are warranted.