State and city inspectors have been making spot checks of the temperature of food being transported by ferry to restaurants and markets on Casco Bay’s islands, in response to worries about unrefrigerated shipments sitting on docks for hours.

Although no one has reported getting sick, health officials say distribution companies were notified and have taken steps to improve preservation methods, including adding more ice and insulation to food deliveries.

Casco Bay Lines has responded to the concerns raised by the city last month by moving shipments of food inside its building to a cooler environment, and in a few instances turning away delivery trucks that arrive at odd hours. Most ferry deliveries occur during daytime hours.

“They’ve got a plan in place to make sure this doesn’t happen any more,” said Jessica Grondin, spokeswoman for the city of Portland.

The food storage concern came to light July 8, when a city health inspector noticed a shipment of food sitting on a Casco Bay Lines dock in Portland without refrigeration.

Food deliveries to Casco Bay Island communities have gone on for years, and Grondin said it was unclear to her why food storage suddenly became an issue for the inspection division.

Grondin said the inspector notified Michael Russell, manager of Portland’s Environmental Health and Safety Division, who in turn alerted the state.

“We’re in the early stages of uncovering a potentially significant ongoing food safety hazard,” Russell said in a July 8 email to state officials.

Russell went on to say that the shipments also sit in the open on the ferries for the trip to the islands, and again on island docks until customers pick up their orders.

City and state officials said they have had no reports of illnesses caused by food shipped to the islands. It is not clear how much food or which food service businesses would be affected by unrefrigerated deliveries. The operator of one island restaurant, for example, said the business transports deliveries in a refrigerated truck. Casco Bay Lines has the capacity to transport cars and trucks to island communities.

Grondin pointed out that three of the islands involved – Peaks, Great Diamond and Cliff – are part of the city and therefore its responsibility. She said the state is responsible for oversight of food from the wholesalers to their customers.

“We don’t have jurisdiction over the food until it actually gets to the restaurant,” Grondin said.

Russell’s email suggests that health officials may need to develop more standards to determine if the food being shipped is in danger of going bad.

Last week, an agency of the Maine Department of Agriculture, Conservation and Forestry randomly tested the temperature of food shipments on the mainland dock and found that the shipments met the 41-degree requirement for preventing spoilage. More random tests will take place in the weeks to come, said Ron Dyer, director of quality assurance and regulation.

Dyer’s agency also contacted all of the distributors and retail stores that ship food to the islands. Those businesses agreed to beef up their refrigeration methods.

“They have jumped right on top of this by making sure that the food shipments are being properly refrigerated all the way to the dining room table,” Dyer said.

He has not been in contact with Casco Bay Lines, which he said simply serves as the “taxi” for food deliveries to the islands.

“It’s better if the shipments are being moved quickly, but it’s not always possible,” Dyer said.

Nicholas Mavodones Jr., operations manager for Casco Bay Lines and also a Portland city councilor, said the ferry service does not have the capability to refrigerate food shipments at its terminal off Commercial Street. Mavodones said his staff has on occasion turned away delivery trucks that show up too early in the day.

One distributor has even taken the step of having its delivery truck ride the ferry to Peaks Island, Mavodones said. His workers also have started coordinating with vendors to arrange convenient delivery times.

“We don’t always control when these delivery trucks show up,” Mavodones said.

He said the ferries make food shipment deliveries several times a day to all the islands. He did not know the tonnage being handled.

Retailers on the islands have seen some of the spot temperature checks taking place.

Kiernan Somers, manager at Down Front Ice Cream on Peaks Island, has seen health inspectors at the island ferry terminal during the past couple of weeks checking food temperatures when people pick up their orders.

He said food shipments are usually the last to come off the ferries, mixed in with other cargo.

“It’s very busy depending on the time of day,” Somers said. “The system can definitely be improved.”

Matt Joey, general manager of the Inn on Peaks Island, said his business has not been affected, since the distributor brings the food and beer kegs over to the island on a refrigerated truck that travels on the ferry.