A catering company in Wales has been fined in relation to five people who became ill from eating mackerel in July 2019.

DM Catering (Pembs) Ltd. was fined £2,550 ($3,300) by Haverfordwest magistrates in late September after pleading guilty to storing foods likely to support the growth of pathogenic microorganisms or the formation of toxins at a temperature above 8 degrees C (46.4 degrees F).

The prosecution was brought by Pembrokeshire County Council’s Environmental Health department.

The court heard that in late July 2019, five people who had eaten mackerel at Martha’s Vineyard restaurant on Milford Marina became unwell with gastrointestinal symptoms and headache. One person also experienced a skin rash, short, rapid breathing, a rapid pulse and a temperature. Another person’s symptoms begun before leaving the restaurant.

Histamine or Scombroid fish poisoning can be caused by eating species of marine fish such as mackerel that have high levels of histamine in their tissues. onset of symptoms can range from minutes to several hours following ingestion of toxin.

Food had been taken home by the group to finish later. That sample of mackerel was collected and sent by the council for testing by the Public Analyst. Analysis found it was unfit for human consumption.

Temperature troubles
A visit to Martha’s Vineyard by an environmental health officer found some refrigerators in the kitchen were operating at too high a temperature. The core temperature of some foods within the fridges was as high as 22 degrees C (71 degrees F).

Temperature checks had been carried out by the business but the method of getting results – reading the dial on the refrigerator rather than using a temperature probe – had proven to be inaccurate.

Any high risk foods stored above 8 degrees C (46.4 degrees F) could have increased levels of pathogenic microorganisms, including bacteria such as Listeria and toxins in scombroid fish such as mackerel. Production of histamine is related to mishandling of food due to storage at incorrect temperatures. once histamine has been produced, it cannot be eliminated by normal cooking or freezing temperatures.

All affected food was disposed of and an engineer repaired and replaced the refrigerated units. The business was co-operative during the investigation by Pembrokeshire County Council and has implemented better monitoring practices to ensure that all foods are stored at 8 degrees C (46.4 degrees F) or less.

Councilor Cris Tomos, cabinet member for Environment, Public Protection and Welsh Language, said: “This case was important in showing that food businesses must be extremely diligent when storing foods that pose a risk of supporting the growth of bacteria and toxins. It is of the utmost importance to ensure that the temperature of such foods is managed effectively and that the temperature monitoring equipment relied upon, is accurate.”