1) Pains 2) Thorns 1) Pollen and dust, notoriously 2) Smoke, dust, pollen, etc 
Drugs that act locally on cutaneous or mucosal surfaces to produce inflammation; those that cause redness due to hyperaemia are rubefacients; those that raise blisters are vesicants and those that penetrate sebaceous glands and cause abscesses are pustulants; tear gases and mustard gases are also irritants. ... (12 Dec 1998) ...