(Courtesy of ICE)

On Oct. 31, ghouls, goblins and other macabre creatures stalk the streets of America, threatening every homeowner with a sound toilet-papering if they do not surrender their sugary treats.

But those creatures of the night who don decorative, black-market contact lenses may face problems of their own on All Hallows’ Eve, including bacteria and conjunctivitis. That warning is according to U.S. Immigration and Customs Enforcement, the Food and Drug Administration and U.S. Customs and Border Protection, which are teaming up in the battle against substandard, unapproved eye wear.

“Criminal elements will capitalize on the excitement of the holiday season by selling substandard, dangerous, counterfeit and illegal items with no regard for the health and safety of consumers,” Peter Edge, the executive associate director for Homeland Security investigations, said in a statement Monday. “Our agents are committed to collaborating with external agencies to develop effective operations and conduct aggressive investigations into the distribution of fake goods that threaten the American public with lengthy medical procedures and strenuous rehabilitation programs.”

About 100,000 pairs of “counterfeit, illegal and unapproved contact lenses” have been seized, according to the statement, in an FDA-led mission called Operation Double Vision. Improperly stored or shipped contacts can shelter bacteria, and lead-based materials can leach directly into the eyes of unsuspecting trick-or-treaters.

Though just 11 percent of consumers have worn decorative contact lenses, the statement said, a majority of those have bought them without a prescription.

“You’d never buy a new hip at a flea market, and you should never buy a medical device like contact lenses at one either,” Ben Casella, president of the Georgia Optometric Association, said in a statement. “If you’re not careful, one night of using knockoff lenses to change your appearance can mean a permanent change in your ability to see for the rest of your life.”