Of course, air pollution has negative impacts on human health, but does it also lead to an unproductive workforce? It seems that way:
[R]esearchers found that a 10 ppb (parts per billion) change in average ozone exposure results in a significant 5.5 percent change in agricultural worker productivity. "These estimates are particularly noteworthy as the U.S. EPA is currently moving in the direction of reducing federal ground-level ozone standards," said Dr. [Matthew] Neidell, PhD. This past September President Obama said he would not support a proposal by the Environmental Protection Agency to tighten the federal ozone standard because it would pose too heavy a burden on businesses...
Those findings come from a study published in the American Economic Review by Matthew Neidell, a professor at Columbia University's Mailman School of Public Health. What's crazy is that even when ozone levels were below federal air quality standards there were still "significant negative impacts" on workforce productivity. Neidell believes his research can help to flip the thinking that dealing with pollution has a negative impact on businesses to seeing it as an investment in human capital.
Ozone Levels Have Sizeable Impact On Worker Productivity [Science Daily]