Handling Seafood Safely
In the United States, it is extremely rare for individuals to become ill as a result of having eaten fish. Carefully prepared in a clean environment, even raw finfish, which is becoming more popular as we explore cuisines from around the globe, is almost never a cause of illness.
In brief, for eating raw finfish safely, using best safety practices avoids cross-contamination from bacteria and parasites.
To avoid cross-contamination:
- Purchase seafood from a clean shop with knowledgeable employees. Seafood should never be displayed or stored in a way that other foods can cross-contaminate them, especially poultry. Hands should be washed before handling, or gloves should be changed, and utensils should be used for handling one type of seafood.
- Practice safe hygiene at home; wash cutting boards, knives, utensils, and your hands with hot, soapy water before preparing seafood meant for raw or cooked consumption.
To avoid parasites:
- Choose only the freshest fish. Most parasites migrate from the belly cavity area through the fish after it dies.
- Avoid wild freshwater fish such as whitefish, pike, perch and lake trout; tapeworm is endemic to those fish.
- Learn to identify the culprits in fish; they are visible to the naked eye.
- Prepare raw fish at home very carefully. Slice it thinly and examine it. As an extra precaution, put the fish on a piece of plexiglas and hold it over a light bulb so any parasites will be
While only 5 percent of all food borne illnesses are seafood related, 85 percent of those illnesses can be traced to eating raw mollusks such as clams, oysters and mussels. Naturally occurring bacteria that thrive in a salty environment, marine toxins related to algae blooms and polluted runoff-related viruses and bacteria that enter harvest areas can all be responsible for illness.
There are shellfish that are at risk of cross-contamination that are also eaten raw, such as abalone and lobster, and those mollusks of which only muscle is eaten, like scallops and goeduck clams.
Local, state and federal health agencies regularly monitor shellfish beds and farms. Water and shellfish samples are taken from the harvest areas weekly and are analyzed for the presence of natural toxins and pathogens, and harvest areas are closed if anything is detected. Harvest areas are also shut down as a precaution during heavy rains.
In brief, where your raw shellfish comes from and how it is handled is key in assuring safety.
To avoid consuming contaminated raw shellfish:
- Purchase seafood from a clean shop with knowledgeable employees and displays National Shellfish Sanitation Program (NSSP) tags with all mollusks. The NSSP requires mandatory tracking of harvest location and dating of all commercially harvested shellfish to ensure that the harvest has taken place in waters that are certified to be safe at the time of harvest.
(The harvest of contaminated shellfish by ill-informed recreational harvesters is responsible for the great majority of shellfish-related illness.)
- Give first preference to locally grown shellfish without far to travel.
- Eat raw shellfish only in clean restaurants where you have confidence in the abilities of the chef and staff.
- Eat raw shellfish during the cool winter months. Warmer waters encourage algal blooms and in some locations, refrigeration can be compromised.
- Avoid raw shellfish in areas of the world where sanitary systems may be inadequate, especially in the warmer areas of the tropics.
To be safe, pregnant women, young children, individuals with diabetes, cirrhosis, leukemia, AIDS, or chronic disease, such as those with immunosuppressive drugs or chemotherapy should not consume raw shellfish at any time.