A report issued Wednesday by environmental groups ranked the Lehigh cement plant in Mason City as eighth-worst in the country for mercury emissions, but a spokesman for the company says the report doesn’t tell the full story.

Tim Matz is Lehigh’s director of environmental affairs in North America. "Mason City in the past has for construction purposes has put on state-of-the-art pollution control equipment and some of that pollution control equipment will help in mercury emission reductions," Matz says.

The environmental groups accuse the U.S. Environmental Protection Agency of a cozy relationship with the country’s cement industry that has resulted in lax regulations. Matz says Lehigh has closely worked with state and federal environmental officials in trying to lessen the impact of pollution coming from the plant.

"We’ve put on controls for nitrogen oxide emissions…and also sulfur dioxide emissions so we’ve incorporated two systems at Mason City to reduce both those pollutants and the one that has the (sulfur dioxide) should have a direct implication on reducing mercury emissions," Matz says. "That’s what we’re looking at and working with EPA on — what kind of controls are out there and exist for the cement industry as far as mercury emissions."

Specifically, Matz says the report from the environmental groups does not use the right data to make its conclusions. "The report just looks at what our inputs are…so it doesn’t take into account the control equipment we have right there in Mason City," Matz says.

The Sierra Club, Earthjustice and the Environmental Integrity Project say mercury is an extremely toxic substance and regulators should do more to ensure it isn’t contaminating lakes, rivers and streams. Pregnant women, for example, are advised to avoid eating fish because of mercury levels which could harm their babies.