Table 2.

Respiratory and Allergic Outcomes Associated with Early-Life Air Pollution Exposures.

Health Outcome	Population Age	AP Exposure	Exposure Time Window	Association	References
Lung function	5–9 years	PAH	Prenatal	↓ FEV1	[95]
	5–7 years	Near-roadway air pollution (NRAP), TRAP	Postnatal	↓ FVC, ↓ FEV1	[96,101,106]
	2–10 years	NO2, PM10, PM2.5, NO3	Prenatal	↓ FVC, ↓ FEV1, ↑ respiratory resistance, ↓ respiratory reactance	[97,98,99,100,103,104,105]
	2–10 years	Household air pollution	Postnatal	↑ Airway reactance, ↓ FEV1	[99,102]
	30 days–1 year	PM10, CO, NO2, O3	Prenatal	↑ Fractional exhaled NO, ↓ peak tidal expiratory flow, ↑ respiratory rate, ↑ minute ventilation	[92,93,94]
Respiratory tract infections	12–18 months	NO2 and PM2.5	Prenatal	↑ Lower respiratory tract infections, ↑ LRTI hospitalizations	[108,110]
	0–5 years	PM2.5, PM10, NOx, O3, SO2	Postnatal	↑ Respiratory infections, ↑ bronchitis, ↑ LRTI hospitalizations	[130,136,137,138,139,140,141,142,143,146]
Asthma and allergic disorders	Newborn	PM2.5	Preconception	↑ Transient tachypnea, ↑ asphyxia, ↑ respiratory distress syndrome	[107]
	0–10 years	SO2, NO2, PM10, PM2.5, black carbon, CO, ultrafine particles, regional NO2	Prenatal	↑ Wheeze, ↑ asthma	[109,111,112,113,114,115,116,117,118,119,120,121]
	3–6 years	PM2.5, PM10, NOx, PAH, SO2	Postnatal	↑ Allergic symptoms, ↑ allergic rhinitis, ↑ eczema, ↑ asthma	[102,114,115,119,120,123,124,125,126,127,128,129,130,131,144]
	0–10 years	TRAP	Postnatal	↑ Asthma, ↑ asthma hospitalizations	[122,132,133,134,135,145]
	0–5 years	Ambient air toxics	Postnatal	No association with asthma	[147]
	0–5 years	Wildfire-generated air pollution	Postnatal	↑ Respiratory hospital visits	[148]

↑: increasing, ↓: decreasing.