How much exposure to wood/ paint dust would cause permanent lung damage ? I have been doing some exterior sanding on my house for the past few months using a paper nose/mouth mask intermittently. Last Sunday the mask strap broke and I continued with my sanding then used a shop vac to pick up the wood/paint dust. I inadvertently inhaled some of the dust that escaped through the exhaust port of the vac. Later that day noticed mild shortness of breath at rest, no wheezing or coughing. I went to urgent care and my blood oxygenation was 99% and lungs were clear. I am still having some shortness of breath. Could this just be some irritation or more serious ?