Leafy greens have the dubious distinction of being on the Center for Science in the Public Interest's "Top 10 Most Dangerous Foods" list because of the number of foodborne illnesses linked to the salad staple.

A team of Ohio State University researchers wants to find out why the disproportionate number of outbreaks occurs and how to prevent them, according to a news release.

The answer may lie in the porous leaves, which aid in respiration but also provides an easy entrance for pathogens.

The leaves also are much more sensitive to treatment than other types of produce.

Products that may kill the pathogen may damage the leaf, making it unmarketable.

Freshly harvested leafy greens are typically vacuum-cooled, washed and sanitized with a chlorine solution before packaging.

The liquid sanitizers are not always effective and may even worsen the problem, says Ohio State University food engineer Gonul Kaletunc.

Air bubbles can form in the liquid sanitizer, preventing it from ever eaching the leaf surface.

Even if the sanitizer does come in contact with the leaf, it may not have enough contact time to penetrate the leaf deep enough to reach the pathogens.

The U.S. Department of Food and Agriculture has provided the team with a $1 million grant to explore gaseous sanitizers, including ozone and chlorine dioxide.

Although the gas can penetrate the leaf crevaces, they pose handling challenges.

To read more about the Fresh Produce Safety Initiative at Ohio State University, Iowa State and New Mexico State University, click here.