Anthropogenic emissions are also the most toxic.
Adverse effects of any pollutant can be estimated from the interaction of several factors, including the toxicity of the agent, its concentration, length of exposure, and the biological vigor of the receptor. Our lungs are our personal link to the atmosphere. It is here that polluted air excercises its most devastating health effects. In a pollution-filled environment, toxicity, concentration, and exposure time are maximized. Those most at risk include infants, the elderly, and those already at risk for lung disease.