Ackee and Jamaican vomiting sickness
In recent weeks, there has been an increase in the incidence of food intoxication and death caused by the consumption of meals containing the Jamaican ackee.
Consider the national and global incidence of ackee poisoning (blighia sapida intoxication). In March 2023 alone, there were five cases of the illness and one associated death in Jamaica. Globally in 2015, nine Nigerian children also experienced neurotoxicity after consuming roasted ackee seeds. Over the years Haiti, French Guiana and Suriname has also recorded cases of food-borne illness due to the consumption of ackee arils (yellow part) or the seeds.
General properties of the Jamaican ackee fruit
The ackee (blighia sapida), which is also called the Jamaican ackee, is a member of the sapindaceae family. The fruit of some sapindaceae is normally embedded in a capsule or pod that opens between the internal partitions when they are mature. Approximately 2,000 species of sapindaceae, such as the Jamaican ackee, grow within temperate to tropical regions throughout world and are normally studied for their pharmacological activities such as antioxidant, anti-inflammatory and anti-diabetic properties.
Food safety and nutritional characteristics of the Jamaican ackee (blighia sapida)
Mature ackees are safe to eat and are not only delicious but are also found to be a source of nutrients such as in protein, fats and vitamins. Consumption of ackee has also been associated with the promotion of digestive health, stabilisation of the body’s glucose levels, improved heart and bone health amongst other health and dietary benefits. Amidst the proven benefits, the arils (yellow part) are the only edible portion of the fruit hence differentiating the ripe from the unripe ackee is necessary to prevent any associated risk of food intoxication.
What makes the Jamaican ackee (blighia sapida) poisonous?
Ackee arils (yellow part) contains high levels of the heat stable toxin hypoglycin A at approximately 1,000 ppm. As the fruit matures, the levels of toxin is drastically reduced to nearly 10,000 times less the concentration that is in the immature fruit. Ackee pods and seeds are also high in hypoglycin and even after the fruit has matured, the toxin in the seeds and pods remain very high, making these parts of the fruit inedible and always toxic. This, therefore, means that ackee toxicity only occurs when there is the ingestion of the unripe ackee arils, the ingestion of ackee seeds or cross contamination of foods with the hypoglycin toxin found in ackee.
Signs and symptoms associated with ackee poisoning
Ackee poisoning is a food intoxication caused by the hypogylcin A or B toxin. The illness, which is referred to as “Jamaican vomiting sickness”, usually has an onset within 6 to 48 hours after consuming a meal containing the toxin or toxins. Severe hypoglycaemia, accompanied by convulsions and death, cholestatic jaundice, vomiting, and coma are also associated symptoms of the illness.
How to differentiate between the ripe and unripe ackee fruit (blighia sapida)
The Jamaican ackee fruit that is ripe has a completely open pod which is normally yellow to red colour. When the fruit is mature all parts of the seeds and arils are also visible hence no need for further opening of the pod. In contrast, unripe ackee pods are normally unopened and green to yellow in colour. The seeds of the unripe fruit is barely visible; therefore, ackee should be rejected if there is evidence of forced opening such as the absence of a smooth surface between the partitions of the pods.
Food safety measures to observe when selecting and preparing the Jamaican ackee (blighia sapida) for consumption
Ensure that all the arils in the pod are fully visible before the ackee is considered edible. A slight opening in the pod does not mean that the fruit is safe to eat. Ackee pods should be allowed to open, naturally and fully.
Do not:
• Consume ackees which show signs of immaturity as cooking does not reduce the hypogylycin toxin in the arils.
• Eat ackee seeds or cook ackee seeds. Vigilance should be exercised to ensure that all the seeds are removed from amongst the arils prior to cooking.
• Cook other food items in the water with raw ackee: Codfish, ground provision or any other food item that will constitute a part of the intended meal should be cooked separately.
• Consume the water used for boiling the ackee arils, instead the water should be drained from the cooked arils and disposed of in a safe manner.
Other precautionary measures worth observing
Buy ackee from trusted sources only, especially when the arils are already removed from the pods.
Wash hands after handling raw ackee and before handling other foods; ackee pods and seeds contain high levels of hyploglycin, the possibility for cross contamination of other foods through the hands is therefore likely.
Vigilance, policy and strategies will reduce morbidity and save lives
Undeniably ackee-related food intoxication has resulted in numerous illnesses and deaths worldwide. Also, 194 cases of ackee poisoning in Jamaica in 2011 and 23 associated deaths in that same year coupled with repeated international trade restrictions placed on ackee exports from Jamaica is evidence of the fact that increased consumer vigilance, more efficient polices and strategies to reduce the risk associated with ackee-related food-borne illnesses are long overdue. Ackee is the national fruit of Jamaica and is widely consumed throughout the society. Understanding the seriousness of the illness and risk posed to the population due to the consumption of this fruit, stakeholders with responsible for food safety, plant health and epidemiology must collaborate and proactively implement and enforce more effective strategies and polices geared towards ensuring the protection of the public’s health. Polices which are comprehensive and not just bias towards the protection of the ackee export market as well as more research and public education relating to ackee toxicity will avert or minimise the continuous negative effect relating to incidence of ackee poisoning in Jamaica.
Karlene Atkinson is a public health specialist and lecturer at the School of Public Health, University of Technology, Jamaica.