aerosol hazard.. a chemical or biological hazard and how?

aerosol hazard.. 

a chemical or biological hazard and how?

chemical properties (vapor pressure, vapor density, molecular weight, relative size) and how they affect the different routes of exposure.

What exposure route is the most important?

What way can substance could enter the body through the dermal route, and why the dermal route would or

would not be important.

region of the respiratory system where deposition would be expected