From:  An expert position paper on environment, occupation and climate change effects on allergic respiratory diseases in Italy

 Environmental risk factors for asthma and COPD.

Environmental risk factorImpact on asthmaImpact on chronic obstructive pulmonary disease (COPD)Main agents and sources
Air pollution (outdoor)It increases the incidence (especially in children) and causes exacerbations. Promotes allergic sensitization.It accelerates the decline in lung function and increases the risk of developing and exacerbating the disease.Particulate matter (PM), nitrogen dioxide (NO2), ozone (O3) deriving from vehicular traffic and industrial emissions.
Domestic pollution (indoor)Exposure to allergens causes onset and exacerbation. Secondhand smoke is a key risk factor.Biomass burning is one of the main global causes. Passive smoking increases the risk.Allergens (mites, moulds, animals), second-hand smoke, smoke from burning wood/charcoal for cooking or heating. Volatile organic compounds (VOCs).
Occupational exposuresCause of occupational asthma (sensitizing or irritative), the most common occupational respiratory disease.About 15–20% of cases are attributable to work. Cause of chronic inflammation and lung damage.Asthma: flours, isocyanates, latex, wood dust. COPD: mineral dusts (coal, silica), organic dusts (cotton, cereals), chemical fumes.