Rainbow Smelt (Osmerus mordax) With Bad Odor and Taste

The smelt, caught through the ice in late January, may have caused a person who ate some to get sick. Local, tribal and state officials worked together to collect and analyze the fish.

Austin Ahmasuk of Kawerak writes:

This morning I received a call from Percy Nayokpuk about a concern that has developed regarding smelt among residents in Shishmaref. He mentioned people are getting a lot of smelts but they have a bad taste. He mentioned people are leery of eating them. He mentioned there have been two cases of cancer in last couple weeks. He is wondering if they are safe to eat. He mentioned the likelihood of getting smelt samples would be good.

Note: this observation was posted on behalf of Percy Nayokpuk and Austin Ahmasuk by LEO Member Anahma Shannon of Kawerak Association. (02/07)

On February 12, 2019 at 10:00 Percy Nakokpuk stated in a phone interview (as recorded by Mike Brubaker):

I learned about this event from my sister Joan Hjalseth who lives in Anchorage. Some relatives collected these fish for her. Every since December the fishing has been on the back (south) side of Shishmaref. The fish were caught just off shore where the deep water starts in the lagoon. The person who got sick ended up in the emergency room (Alaska Native Medical Center) shortly after eating the fish. When she started to eat them they tasted liked exhaust fumes. That is what alerted me. I checked in to it and heard from others that had the same problem. I am not sure that this is an isolated incident. What would cause this? Is this from a petroleum spill? What comes to mind to me is that Shishmaref has been the sight of some very big oil spills which have never been cleaned up.There was one in the 70s that was reported as a 100 gallon spill. But it was really much bigger. The slick was visible from Shishmaref to Diomede, 70 miles away. That was a spill of home heating oil.There are parts of the island where there are ten feet of soil contamination. The second big spill was a leak from an oil line. That went undetected for several years. It was in the same area as the first spill, which is shown on the ADEC contaminated site list. Anything underground would have to be effected by the permafrost. I just wonder if there are pockets of fuel that are leaking out.

Fish Examination - Consult by Dr. Jayde Ferguson with the State of Alaska Department of Fish and Game, Fish Pathology Lab:

There were no clinical signs of disease in the fish that were submitted. Therefore the strong, unnatural odor is likely due to a chemical that the fish has come into contact with or has assimilated into the body through the food chain. A somewhat similar phenomenon has been reported in the literature that involves dimethyl sulfide or DMS causing an oily flavor in fish. DMS is proposed as the byproduct of fish consuming sea snails of the species Limacina helicina that feed on marine algae. Fermentation of the snail occurs in the gut and then compounds concentrate in the muscle of some herbivorous fish, including chum salmon. Low levels of DMS occur in asparagus, cabbage, corn, and seafood when cooked, but there have been no reports of foodborne illness associated with this compound. However, there could be a dose response where high levels could produce clinical disease. The remaining frozen fish were sent to DEC for organoleptic (i.e. odor, see below) testing and potentially other tests to determine the compound responsible for this condition.

Fish Odor Test - Consult by Dr. Bob Gerlach with the State of Alaska Department of Environmental Conservation:

I spoke to the analysts who performed the organoleptic (odor) evaluation of the smelt. There appeared to be an off odor when the smelt were removed from the plastic bag. The fish were placed on cleaned dishes and then after 15 to 20 minutes evaluated. There was no detection of any abnormal odor, texture or visual appearance. From this I was concerned that the abnormal odor may have originated from the plastic bags that the fish were stored in. In cases of food borne illness that may be caused by many things (chemical/toxin, virus, bacteria) the investigation generally follows along the evidence collected from the patient during visit to the medical facility or doctor’s office: signs, symptoms and diagnostic test results from any samples taken from the patient. This information from the doctor or hospital is what the investigators use to direct testing of the food consumed, in this case the smelt. These types of cases can be challenging to deal with when no definitive answers can be identified.

Please note laboratory report findings: 14 smelt were received for this sample. After testing, the entire sample was delivered to the AK Public Health Lab for additional testing. The "PASS" result indicates no unusual odors or appearances were discovered, no visual evidence of decomposition or external anomalies.

Fish Chemical Test - Consult by David Verbrugge, State of Alaska Department of Health and Social Services:

We did not find anything on the surface of the fish and what was in the fish muscle may be natural. It is in determinant. We definitely did not find any oil related compounds and the sulfide compounds that we found, those smell very differently then the musty, fuel odors that people were describing in the field. The carbon disulfide and dimethyl sulfide, those compounds smell much more offensive, like rotten cabbage.

Consult by Dr. Louisa Castrodale, State of Alaska Department of Health and Social Services:

When DHSS is alerted to concerns about illness or exposures with possible health impacts, we contact local partners in public health nursing, environmental health, and local/regional medical staff, to see if they are aware of suspected illnesses or issues. For this situation, there was no information received that suggested the occurrence of illnesses related to smelt.

Consult by Sharon Nayokpuk with the Shishmaref Tribal Council:

People continued fishing after this event and we have not heard of any other problems and no further reports of people getting sick or of bad fish. No one is fishing right now because the weather has been bad for weeks. It keeps getting stormy. Once the weather improves again, people will go back to fishing including smelt.