How consumption of kodo millet led to the death of 10 elephants in MP

The tropical and subtropical regions are best suited for Kodo millet cultivation and it is grown on poor soils, and widely distributed in arid and semi-arid regions. Apart from MP, the millet is cultivated in Gujarat, Karnataka, Chhattisgarh, and parts of Tamil Nadu.

Some of the famous dishes that can be made with kodo millets include idli, dosa, papad, chakli, porridges, and rotis.

Why do farmers grow kodo millets?

Kodo millet is a staple food for many tribal and economically weaker sections in India. It is one of the “hardiest crops, drought tolerant with high yield potential and excellent storage properties,” according to researchers.

They said kodo millet is rich in vitamins and minerals. Researchers also claim that the millets are gluten-free, easy to digest, are a great source of antioxidants, and “might have anti-carcinogenic properties.”

A 2019 research paper states that the “presence of dietary fibre in the seed coat of millet grains is beneficial to human health which affects several metabolic and digestive processes, such as effects on glucose absorption and cholesterol levels.”

What are some of the earliest known cases of kodo poisoning? 

One of the earliest known documentation of kodo millet poisoning was in the Indian Medical Gazette in 1922. There were about four cases of acute poisoning brought in by the police on March 4, 1922, and its details were written by Anand Swarup, an Assistant Surgeon from Shahjahanpur in Uttar Pradesh.

The patients included a 50-year-old woman, a 22-year-old man, and two boys aged 12 and 9 who were all brought in unconscious. They were revived after their stomach was washed out. The patients were also vomiting continuously for several hours and shivering from the cold. The patients told the police that they had consumed bread made from ‘Kodon’ (kodo) flour. An hour after consumption they began vomiting and fell unconscious.

The first animal documented to have kodo poisoning was in February 1922 when Swarup wrote that a landholder from Tilhar told him that a dog which had eaten a kodo-made bread fell sick.

A 1983 research paper, ‘Diversity in Kodo Millet’, documented for the first time the death of elephants from eating kodo millet.

According to a 2021 research paper, ‘Kodo poisoning’: cause, science and management’, in 1985, the reasons for kodo poisoning first came to light after researchers established “the association of the mycotoxin, cyclopiazonic acid (CPA), with kodo millet seeds causing ‘kodua poisoning.”

Why do kodo millets become poisonous? 

According to a 2023 research paper, ‘Potential Risk of Cyclopiazonic Acid Toxicity in Kodua Poisoning’, published in the journal of scientific and technical research, kodo millet is mainly cultivated in dry and semi-arid regions. However, sometimes “environmental conditions like spring and summer strike as being suitable for a certain kind of poisoning which leads to greater economic crop loss.”

“Millets are more prone to fungal infection followed by bacterial and viral; these infections adversely affect the grain and fodder yield. Ergot is a parasitic fungal endophyte that grows in the ear heads of various blades of grass, most frequently on kodo millet. Consumption of such kodo grains is often found to cause poisoning,” the paper said.

According to the paper, “CPA (Cyclopiazonic acid) is one of the major mycotoxins associated with the kodo millet seeds causing kodo poisoning which was first recognised during the mid-eighties”.

Kodo poisoning occurs mainly due to the consumption of kodo grains, when “maturing and harvesting if the grains had encountered with rainfall, resulting in a fungal infection leading to ‘poisoned kodo’ which is locally known as ‘Matawna Kodoo’ or ‘Matona Kodo’ in northern India.”

Once infected, “feed or food containing mycotoxins are condemned since these toxins are strong and stable against thermal, physical, and chemical treatments during food processing.”

What is the impact of the toxic grain on animals? 

Kodo poisoning mainly affects the nervous and cardiovascular systems and the chief symptoms include “vomiting, giddiness, and unconsciousness, small and rapid pulse, cold extremities, shaking of limbs and tremors.”

Since CPA is the prime constituent of kodo poisoning, toxicity studies have shown degeneration, necrosis, and liver dysfunction,  lesions of the myocardium, by affecting calcium signalling in the heart, leading to cardiomyocyte damage and impaired heart function as some of the symptoms.

Studies have also shown that CPA can cause “gastrointestinal disorders in animals and can elevate the production of reactive oxygen species (ROS) in the intestine, which can lead to inflammation and damage to the gastrointestinal tract.” The doctors who treated the sick elephants had reported the same symptoms.

Researchers have also tested the impact of the toxic grain on mice which showed “symptoms of depression and complete loss of mobility.”

What is the solution to kodo toxicity? 

Researchers have advocated the use of biocontrol agents, meaning the “use of an organism to fight against another organism” in the case of kodo poisoning.

Many microbes have been shown to “minimise fungal development and mycotoxin secretion,” according to the researchers. They also advocate the growth of “competitive, non-toxigenic strains of the same fungi” as a “biological control strategy that appears to be effective in inoculating the fields for many years.”

However, this won’t be enough. It has also been suggested that farmers should follow “good agricultural practices coupled with good post-harvest management like sorting and proper storage, preferably in hermetic/airtight devices to significantly decrease mycotoxins.”

Since the fungi spread fast in the moist environment “harvested heaps must be sheltered from the rain” and the “old practice of threshing by moistening the plants before threshing should be stopped.”

Removing the infected grains also “helps in reducing the spread of the disease.”

When was the last time kodo poisoning led to death? 

Wildlife department officials in Madhya Pradesh have said in 2022 one elephant died after ingesting toxic kodo millet. However, there have been no reported deaths of human beings due to kodo millet poisoning, according to researchers. This is because poisoned persons could be recovered by “washing out the stomach, by giving stimulants, hot tea or milk.” The signs and symptoms of kodo poisoning persisted for one to three days followed by recovery in these cases.

When treating the elephants, one of the veterinarians said they prescribed “toxicity therapy treatment”, which involved giving medicines in the form of “liver tonics, multivitamins and a general antidote intravenously.”

When harvested for human consumption, how are kodo millets checked for fungal infection? 

Dr P K Chandan, the Additional Deputy Director at Kanan Pendari Zoological Garden in Chhattisgarh’s Bilaspur, said, “It is difficult to spot the toxicity with the naked eye. The plant will look fresh but inside it may have become poisonous due to the presence of high moisture and other factors. You need to do a chemical trace analysis to investigate if the millets have been poisoned.

In the 1986 research paper, ‘Determination of mycotoxins’, said “mycotoxins are usually present in agricultural commodities and products” in the form of “minor constituents in concentrations ranging from (sub) pg—mg/kg, means that the possibilities to determine mycotoxins are limited to certain trace analytical methodologies.”

To determine mycotoxins in kodo millets “Chromatographic (separation of components of a mixture) methods like thin layer chromatography (TLC), gas chromatography (GC), high-performance liquid chromatography (HPLC), and liquid chromatography coupled with a mass spectrometer (LC/MS), are commonly used to detect mycotoxins.”

However, since these techniques are time-consuming, on-site, rapid, and cost-effective detection methods like “enzyme-linked immunosorbent assays (ELISA), lateral flow assays (LFAs), and biosensors are becoming popular analytical tools for rapid detection.”