Are We Being Slowly Poisoned by Food?
By Methmalie Dissanayake
The discovery of substandard coconut oil containers at the Sri Lanka Customs in late March became a major topic of discussion in Sri Lanka for weeks.
This was not the first time the quality of imported food products came into question. In 2008, there was similar controversy regarding Melamine in imported milk powder. In 2013 and 2014, it was reported that imported milk powder and ice cream contained dicyandiamide (DCD). Furthermore, reports emerged in 2019 about adulterated imported milk powder containing “pig fat” (animal fat) and palm oil. Substandard canned fish containers were discovered in 2020. It was reported that the fish contained arsenic.
Appearing on a television program, Director General of Sri Lanka Standards Institute (SLSI) Dr. Siddhika Senaratne dropped a bombshell saying that there are many food items in the market containing aflatoxin and the identity of companies importing them could not be disclosed as entire industries could collapse. She has said the SLSI has no authority to ban the import of products but can only recommend that such products be re-exported or black-list them.
Dr. Senaratne further said that in the case of imported coconut oil, a Sri Lanka Standards (SLS) certificate is not mandatory and that only one company has obtained SLS certification. She has also said that for several years the SLSI has been carrying out its duties and alerting Customs of sub-standard products being imported into the country. In a research conducted on dried chillies, it was found that many samples contained aflatoxin so several companies were not given SLS certification, she said.
SLSI set up by the Bureau of Ceylon Standards Act No. 38 of 1964 is a regulatory institution mainly to protect consumers from unethical business and trade practices.
Her comment sparked controversy as the public started to question the credibility of the certificates given by State institutions like SLSI and the accountability of such institutions towards the citizenry.
The public panicked as they were preparing to celebrate Sinhala and Tamil New Year in which many traditional sweets are made using coconut oil.
It is in this context that the Government Medical Officers Association (GMOA) lodged a complaint against the SLSI Director General in response to recent statements she had made claiming that not only coconut oil but many other food items in the local market contained harmful chemicals.
GMOA Assistant Secretary Dr. Samantha Ananda has said that it could be seen from what Dr. Senaratne says the SLSI has neglected its original purpose of protecting consumers. In a further development, the Sinhale Jathika Sanvidanaya lodged a complaint with the CID requesting an immediate investigation in connection with Dr. Senaratne’s statements.
Meanwhile, the Government also has launched an investigation into the controversial statement, according to Co-Cabinet Spokesperson Keheliya Rambukwella.
What is aflatoxin?
Aflatoxin is family of carcinogens produced by the fungi family Aspergillus (moulds). There are about 14 know types of aflatoxin. But four aflatoxins - B1,B2, G1 and G2 (AFB1, AFB2, AFG1, AFG2) are particularly dangerous to humans and animals, Dr. Piyal Ariyananda, Consultant of Sustainable Innovation and Former BASF Scientist, member of the Royal Society of Chemists said.
These are named following the colour of emitted florescent light observed under ultraviolet rays. Accordingly, AFB1 and AFB2 can emit blue light while AFG1 and AFG2 shows green light. Both B and G types are produced by Aspergillus parasiticus. But Aspergillus flavus produces only B type.
Aflatoxin is produced by fungi grown on crops and develops when crops are stored wet and in humid places for a long time. Aflatoxin could be developed on grains like peanuts, cassava, corn, chilli, rice, paddy, soya and various spices. That is why it is advised to expose them to direct sunlight and store when completely dried. Aflatoxin produced by fungus growing on food remains on food surfaces.
Aflatoxin cannot be seen by the naked eye. It does not have a scent, colour or a taste. Therefore, it is impossible for an average person to detect aflatoxin on food. It could only be seen through thin layer chromatography (TLC) or high-performance liquid chromatography (HPLC) which is not readily accessible to the average person or simple laboratories. Additionally, to determine whether aflatoxin is on food surfaces, purified aflatoxin samples are needed and should be used in specific environments.
Dr. Ariyananda noted that large doses of aflatoxins lead to acute poisoning (aflatoxicosis) that can be life threatening, usually through damage to the liver.Cytochrome P450 in the liver makes aflatoxin active. When this happens, it interrupts DNA replication. Also, it activates carcinogenic cells and makes normal cells carcinogenic. After that, these cells start to grow rapidly inside the body and it leads to cancers.
“The toxicity happens in two ways; chronic toxicity and acute toxicity. Chronic toxicity is the development of adverse effects as the result of long- term exposure while acute toxicity resulted by short-term exposure to the aflatoxin. AFB1 is the most harmful aflatoxin type for humans. The cancers caused by aflatoxin mainly developed in liver and kidneys. When there is long term exposure, especially there is damage in liver caused by Hepatitis B; it is highly possible for a cancer to develop. Furthermore, long lasting stomach infections in children, immune suppression, diseases, and birth defects, infectious diseases are caused by aflatoxin. These conditions are named as aflatoxicosis,” he said.
He further said that if large dose ingestion happens in a single time, it could even lead to death as it harms the liver. Apart from that, nausea, vomiting, lethargy, dizziness could be seen as well.
Adults show higher resistance to aflatoxin than children. The World Health Organisation (WHO) has recommended upper limit aflatoxion ingestion which is 4 μg/kg of all four types of aflatoxion and 2 μg/kg of AFB1. If someone had 20 – 120 μg/kg body weight of AFB1 daily for one to three weeks, it is enough to cause death, it pointed out.
Although a discussion was initiated regarding aflatoxin following the recent coconut oil controversy, a survey conducted by Emeritus Prof. Upali Samarajeewa and Prof. S.N. Arseculeratne in 1983 stated that coconut oil produced by local coconut mills also contained aflatoxin.
They have studied 45 large scale mills in the ‘Coconut Triangle’ of Sri Lanka over a one year period to test aflatoxin contamination - mainly in copra, oil and press cake - to determine the incidence and levels of aflatoxin contamination, and the origin of such contamination. Of 344 samples, approximately 50 per cent contained medium-high levels (0.05 to 1 μg/g, ppm) of aflatoxin B1.
Furthermore, another research conducted by Nuwan B. Karunaratne, Chandima Fernando, D.M.S. Munasinghe and Ruchika Fernando has discovered that 12 out of 32 coconut oil samples obtained from the market (seven branded and five non-branded) contained AFB1 in sizes 2.25–72.70 μg/kg and 1.76–60.92 μg/kg, respectively.Copra is the main source of coconut oils. According to their research, other vegetable oils contained only about 0.8 μg / kg of aflatoxin. This research was released in February 2019, but has not been reported in Media.
Dr. Piyal Ariyananda warned, “Not only coconut oil, but also peanuts, cassava, maize, chilli, rice / paddy, soy, wheat flour, various nuts and spices can also contain aflatoxin, so it is always best to avoid fusty food. The main reason for the increase of cancer in Sri Lanka is the toxins in the food they consume, fertilizers, pesticides, fungicides as well as the various chemicals in processed foods. Also naturally occurring chemicals like these are directly responsible for these conditions. If these standards are not strictly and religiously regulated by the Consumer Affairs Authority or any other responsible agency, it will not be possible to prevent many people in Sri Lanka from getting cancers in the next 20 years.”
Risk of cancers
Dr. Lakshan Abeynayake, Consultant Oncologist at Provincial general Hospital Badulla, said that the main reason for cancers in Sri Lanka is caused by tobacco use, not aflatoxin.
“It has not been proven yet that there is a direct link between the number of cancer patients and food habits in Sri Lanka. Compared to Western countries, the number of cancer patients is minimal in Sri Lanka except oral cancers. If we are able to eradicate tobacco and betel nuts without changing food habits Sri Lankans are used to, I am sure that number of cancer patients in my ward will be reduced by a half,” he said.
According to Dr. Abeynayake, liver cancers are rarely seen in Sri Lanka.
“I have only seen about 10 patients diagnosed with liver cancer per year. 99 per cent of them have consumed alcohol. The main reason for liver cancers is alcohol. Among Sri Lankan men, oral cancers and throat cancers are common. This is due to betel nuts, tobacco and alcohol. Smoking causes cancers in lungs, kidneys, bladder and laryngeal. When people age, they could be diagnosed with cancers too. Majority of cancer cases in Sri Lanka reported due to above reasons. People are dying because of tobacco and alcohol,” he pointed out.
Food safety in Sri Lanka
There is a changing trend in food borne diseases due to emerging socio-demographic factors. Some of them are rapid population growth and demographic shift towards aging population. Others are global market for vegetable, fruit, meat, farm animal which originate from countries without proper microbiological safety procedures, increase travel, changing eating habits of raw and lightly cooked food e.g.: Vibrio due to shellfish, Campylobacter due to undercooked poultry liver pâté, shift, from low to high protein diet, higher proportion of immunologically compromised population, changing farming practices and climate change, a booklet issued by Sri Lanka Medical Association (SLMA) said.
A research titled ‘Food safety in Sri Lanka: problems and solutions’ conducted by J. Munasinghe, A. de Silva, G. Weerasinghe, A. Gunaratne and H. Corke in 2012 noted that food- or water-borne diseases are one of the key issues in food safety assurance in Sri Lanka with increasing incidence levels, partly due to rapid expansion of unsafe retail food establishments over the last few years. Bacterial diarrhoea and hepatitis A, Salmonella infections, contamination by Listeria monocytogenes, and Vibrio cholerea are common sources of food borne disease in Sri Lanka.
“Contaminated milk products also posed high risk. Over the last few decades shrimp farming in Sri Lanka has grown significantly as a high income generating agricultural industry. With the growing demand, many shrimp farms were established in coastal areas. Bacteria of the genus Vibrio are commonly found in the marine environment, and many of the species are pathogenic to humans causing food-borne disease,” the study said.
The researchers has identified mycotoxins are another challenge for the food safety in the country.
“Fungal invasion of commodities before and after harvest, and during distribution and storage, is a well-recognised problem throughout the world. This is especially true in tropical countries, where mycotoxin contamination of food supplies remains a major threat. Aflatoxins, mycotoxins which are acutely toxic, immunosuppressive, mutagenic, teratogenic and carcinogenic, are secondary metabolites produced by some species of Aspergillus, especially Aspergillus flavus and Aspergillus parasiticus. Fungal invasion could take place throughout the food chain from farm, storage, and retail establishments affecting yield, quality and nutritional value of the products. In Sri Lanka, contamination by aflatoxin has been reported for rice, maize, copra, peanuts, pulses and minor food items like spices,” the research cited.
Moreover, pesticides play an important role in modern agriculture. However, recently increased attention has been focused on chemical residues in food. The presence of residues of pesticides in food can present a health risk. The renal failure disease which is prevalent in the North Central Province is believed to have a strong link with certain heavy metals contained in agrochemicals.
They also cited that the fruit and vegetable industry in Sri Lanka is booming with recent growing demand. Toxic and hazardous chemicals such as calcium carbide or ethephon and oxytocin are reportedly being used for artificial ripening of fruits and for increasing the size of fruits and vegetables, respectively.
“Calcium carbide is said to be carcinogenic. The calcium hydroxide formed during the formation of acetylene contains toxic impurities such as arsenic hydride and phosphoric hydride that consumers may then ingest, harming their health. Banana and mango are the fruits most commonly induced by artificial ripening in Sri Lanka. Bananas which are ripened naturally are dark yellow; there are small black spots around the bananas and the stalks are black. Those which are forced to ripen with carbide are often lemon yellow and their stalks green. Moreover the fruit itself is a clear yellow without any black spots.”
What should be done?
Although Sri Lanka has established several effective measures to ensure that consumers receive safer foods there is still much work remaining to be done to fully address certain food safety issues.
“Capacity building and technical assistance are urgently required to prevent contamination of food with pesticide residues, mycotoxins and antibiotic residues in the supply chain. Rice, the staple food for Sri Lankans, needs management under Hazard Analysis Critical Control Point (HACCP) principles in order to eliminate mycotoxins and pesticide residues in processed rice. More Government and public intervention is required to minimise poor food processing, manufacturing, handling and sanitation practices, particularly in the area of fruit ripening and handling.
Effective food regulations and proper sanitary inspections and quality assurance need to be adopted for small-scale food establishments such as food outlets and small restaurants to minimise food-borne infections. To remedy the acute shortage of properly trained personnel such as food inspectors, analytical chemists and microbiologists, it is important to implement further training initiatives in collaboration with international organisations such as the UN Food and Agriculture Organisation. There is also a need for more provincial food laboratories. Resources must be moved towards the most important sources of risk with consolidated authority that can address the food system from farm to table. More public awareness programmes about food safety and sanitation are needed where both commercial stakeholders and consumers need to be involved.”