Those living near Yale’s athletic fields were struck by the familiar stench of pesticides used to maintain the fields this summer, breaking an agreement allegedly reached with the University two years before.

It is not the first time these Westville residents have been exposed to Yale pesticides, said Laura Cahn, a resident of Cleveland Road, which borders the fields. In 2011, she said, she met with two officials from the Yale Office of Facilities who agreed to notify residents the next time they sprayed. But this summer, the pesticides came without warning at the beginning of August.

“It was pervasive — the whole air was filled with this nasty smell,” she said. “The smell is so bad that we can’t even be outside.”

University spokesman Tom Conroy said that he did not know the history of the 2011 meeting. Yale is not in violation of state law, he said, adding that the state of Connecticut found no violation in Yale’s use of the pesticides, as the University only uses approved methods and products in its landscaping.

Conroy said that Yale athletic officials met with residents of Cleveland Road earlier this month and told them they will suspend treatment of the fields in that area while the University explores other options for field maintenance. Residents will be notified when an alternative plan has been developed, he added.

Connecticut forbids spraying pesticides near schools that have students in preschool through eighth grade, barring extreme situations, said Dennis Schain, a spokesman for the Connecticut Department of Energy and Environmental Protection. Schain added that pesticides can be harmful for developing children — a fact that concerns Cahn, the mother of a 14-year-old daughter, who first noticed the smell a few years ago while hosting a party for her daughter and her daughter’s friends. Cahn also questioned the wisdom of exposing college students to a substance that has been deemed unhealthy for children.

Schain said that other institutions in Connecticut likely use pesticides, though it is uncommon to hear concerns from neighbors about their usage. But while the practice is legal, Schain said that “less is better” when it comes to pesticides.

While the practice is not against Connecticut law, Cahn hopes that Yale will conclude that it is best for Yale’s neighbors and New Haven’s environment that the University ceases to use pesticides on its athletic fields.

“Yale is a world leader in so many areas,” she said. “I think Yale can be a world leader in this area, too.”

Of 30 commonly used lawn pesticides, studies have linked 13 with birth defects, 21 with reproductive defects and 26 with liver or kidney damage, according to Beyond Pesticides, a nonprofit organization headquartered in Washington, D.C.