Depending on the substance, airborne contaminants can either cause irritation, disease, or other damage to the tissue of the respiratory system, or contaminants can enter the lungs 
(airborne contaminants; can cause; irritation, disease, or other damage to the tissue of the respiratory system) (contaminants; can enter; the lungs)
airborne contaminants contaminants
can cause can enter
irritation, disease, or other damage to the tissue of the respiratory system
the lungs