The Food and Drug Administration is advising restaurants, retailers and consumers to be careful with scallops that it believes were harvested from prohibited waters in Massachusetts.

Federal officials are recommending restaurants and food retailers not to sell whole, live scallops from Gloucester-based seafood processor and distributor Intershell International Corp., due to contamination concerns after they were received from an unlicensed harvester, according to an FDA advisory Wednesday.

Consumers who may have purchased the affected scallops should not eat them, the FDA advisory warns. Those who may have eaten them and are experiencing symptoms of food poisoning are urged to contact their healthcare provider who will relay the symptoms to a local health department.

The advisory targets businesses and consumers in Massachusetts, Illinois, New Jersey, New York and Pennsylvania, and officials said the scallops “may have been distributed further from these states.”

The scallops were harvested on Dec. 26 and 27, and New Year’s Day, the FDA advisory states.

“Scallops harvested from prohibited waters may be contaminated with human pathogens, toxic elements or poisonous or deleterious substances and can cause illness if consumed,” the advisory states. “Scallops are filter feeders that remove and bioaccumulate bacteria and other pathogens from the water.

“It is not uncommon for shellfish to be consumed raw and whole,” it continues. “Contaminated scallops can cause illness if eaten raw and whole, or with viscera or roe attached, particularly in people with compromised immune systems. Scallops contaminated with pathogens may look, smell, and taste normal.”

The Massachusetts Department of Public Health alerted the FDA last Friday about how the scallops from Intershell International Corp., were “allegedly harvested from a prohibited area and potentially contaminated” and how an unlicensed harvester harvested them from prohibited waters.

State health officials on Tuesday informed the federal Interstate Shellfish Sanitation Conference about the situation, with other impacted states being notified to conduct “trace forward investigations,” according to the advisory.

“The FDA is awaiting further information on distribution of the scallops and will continue to monitor the investigation and provide assistance to state authorities as needed,” the advisory states.