Plans by Foxconn Technology Group for a massive manufacturing complex in Racine County would represent a major new source of air pollution in an area already struggling with summer smog problems. 

Emissions from the company’s operations in Mount Pleasant would rank among the highest in southeastern Wisconsin for pollutants that create smog, also known as ozone pollution, state documents show.

Smog poses a health threat, especially for the elderly, children and people who suffer from respiratory problems like asthma. But it can also lead to reduced lung function for people working and exercising outdoors, and environmental groups are concerned about Foxconn's impact on air quality.