All living organisms, including fish, can have parasites. Parasites are a natural occurrence and are not necessarily due to contamination. Parasites are killed during the cooking process and therefore do not present a health concern in thoroughly-cooked fish. Parasites become a concern when consumers eat raw, undercooked, or lightly-preserved fish (e.g., sashimi, sushi, or ceviche). Freezing, as required under the 2023 Food Regulations, kills any parasites that may be present.

Parasite destruction applies to all raw, undercooked, raw-marinated, or marinated partially cooked fish (e.g., all forms of aquatic life) except those listed in Regulation 3-402.1 (B) (see below).

Fish that does not require parasite destruction is listed in Regulation 3-402.1 (B) and includes:

• Molluscan shellstock
• A scallop product consisting only of the shucked adductor muscle
• Tuna of the species Thunnus alalunga, Thunnus albacares (Yellowfin tuna), Thunnus altanticus, Thunnus maccoyii (Bluefin tuna, Southern), Thunnus obesus (Bigeye tuna) or Thunnus thynnus (Bluefin tuna, Northern)
• Farm-raised fish that have been fed formulated feed (i.e., pellets); and documentation is required
• Fish eggs that have been removed from the skein and rinsed

Except for fish listed as exempted by Regulation, fish that are served raw- or partially cooked must be subjected to parasite destruction by freezing. There are three acceptable time/temperature methods to accomplish parasite destruction. All methods require that documentation or records be kept on-site and available for review during the food establishment inspection. The three acceptable time/temperature methods are:

1. Fish shall be frozen solid and stored at a temperature of -4°F or below for a minimum of 168 hours (seven days) in a freezer.
2. Fish shall be frozen at -31°F or below until solid and stored at -31°F or below for a minimum of 15 hours.
3. Fish shall be frozen at -31°F or below until solid and stored at -4°F or below for a minimum of 24 hours.

Fish that are treated for parasites (frozen) by the food establishment: Records documenting the freezing temperature and time to which the fish were subjected must be maintained at the food establishment for 90 days beyond the time of service or sale as per Regulation. Logs are available for download in the logs and templates section.

Fish treated for parasites (frozen) by the supplier: A written agreement or statement from the supplier that the fish was frozen solid to a time/temperature as specified in Regulation may be substituted for the temperature logs.

Fish that are farm-raised (not treated for parasites be freezing): A statement from the supplier stating that the fish were raised and fed formulated feed shall be retained at the food establishment for 90 calendar days beyond the time of service or sale of the fish.

The Food and Drug Administration (FDA) document, “Fish and Fisheries Products Hazards and Controls Guidance,” contains detailed information on parasites in specific species of fish and also provides information on the process of parasite destruction; or, contact the Food Operations inspector.