Job Osazuwa

Chinedu’s love for banana is beyond the ordinary. Hardly a day passes without the young engineer hunting for the fruit to balance his daily meal. 

This seemingly inseparable attachment with the fruit was recently shaken after he had bought banana at a popular Lagos bus-stop on his way home from work.

Shortly after eating a portion of it, he began to feel a burning sensation in his chest and abdomen, and later followed by mild diarrhoea. His doctor told him that the banana might have been subjected to artificial ripening.

The numerous health benefits of fruits cannot be contested, but some unscrupulous traders, businessmen and farmers have resorted to hastening the ripening process of fruits with calcium carbide, which poses diverse dangers to consumers’ health.

In recent times, a huge chunk of the tropical fruits produced and consumed in Nigeria have become extremely hazardous due to artificial ripening of fruits by different toxic chemical agents.

Investigation revealed that fruits are widely ripened with chemicals in major cities across the country. However, the sellers appear not to be aware or are simply indifferent to how dangerous this act could be to humans. Most consumers, as gathered, are also unaware of the inherent risks in eating such fruits.

Normally, fruits produce a ripening hormone ethylene that induces the natural process of maturation. The process is artificially accelerated by using different chemicals, the commonest being calcium carbide.

It has been unveiled that in a bid to make quick profit and capitalise on the huge national demand for fruits, especially mango, banana, plantain and oranges, fruit dealers use a chemical calcium carbide to ripen them for brisk sales.

A consultant nutritionist and food safety expert based in Lagos State, Adebowale Temitope, warned that the practice of ripening fruits with chemical substances was harmful to human health.

While he described fruit ripening as a natural and unique way of plant development, which makes the fruit edible, softer, sweeter, nutritious and more attractive, he urged those involved in any unhealthy practice to think of the immediate and long term consequences and desist from it.

He explained that calcium carbide, when in contact with moisture, produces acetylene, which is an analogue of natural ripening against hormone ethylene. Acetylene, according to him, is a highly reactive substance used mainly in welding and allied industries.

He also raised the alarm that industrial grade calcium carbide also contains trace amounts of more toxic arsenic and phosphorous that converts the healthy fruits and often makes it poisonous.

According to him, “because people want to make quick sales and profit, they use calcium carbide as ripening agent for mangoes, bananas, melons, avocadoes, pineapples, pawpaw, and other fruits. It is done in many big cities across Nigeria, where demand for fruits is very high.

“What they do is to keep packets of calcium carbide powder in the container of fruits where in contact with moisture, acetylene gas is produced and acts as a ripening agent. Traders pick green fruits before maturation; ripen them artificially to serve in the market earlier than the season for higher profit,” he stated.

Temitope said another reason most traders indulge in the act could be as a result of the fact that green fruits are transported easily with minimum damage. Therefore, the people begin to ripen the fruit at their discretion at the place of retail.

He stressed: “Consumption of carbide ripened fruits is extremely hazardous to health, mainly for the nervous system. Acetylene, generated from carbide reduces oxygen supply to the brain. In acute or at a very dangerous stage, it causes headache, vertigo, dizziness, delirium, seizure and even coma. In the long term, it may produce mood disturbance and loss of memory.

“Other health dangers are that immediately after consumption, there may be abdominal pain, vomiting and diarrhoea. There are usually more cases of people breaking down and complaining of abdominal symptoms after consuming carbide-ripened mangoes. That is why the incidence is high during the season of mango.

“There could also be other toxic effects, which include skin burn, allergy, jaundice and carcinogenic potential.”

Precautionary measures

The expert stated that some precautionary measures to avoid toxic effects to some extent are through washing of fruits before eating and not to eat skin of fruits.

“The above is recommended in case such a fruit is bought unknowingly. But the better option is to buy natural ripe fruits or get mature ones directly from growers and to ripen it at home in warm temperature in contact with one ripe fruit,” he advised.

Many countries across the world, including Nigeria, prohibit the use of any poisonous chemical, like calcium carbide, formalin, pesticides or toxic colour or flavour in any food that may cause harm to human body.

Despite government’s repeated directives to traders to stop this unwholesome practice, chemically treated fruits are selling openly in many markets or super marts.

Concerned Nigerians have called on the bodies in charge of the regulation to be alive to their duties. They demanded the need for the authorities to activate or reinforce definite administrative actions on those promoting the unhealthy fruits. There is a clamour for due attention to be given to awareness creation among traders and consumers.

In April 2018, Nigerian lawmakers urged the executive arm of government to check the sale and consumption of artificially ripened fruits in the country and prosecute those involved. The legislators also charged the National Agency for Food and Drug Administration and Control (NAFDAC) and the National Orientation Agency (NOA) to immediately carry out massive enlightenment to sensitise the public to the menace.

There have been repeated warnings that the acts could cause serious health problems because of their radioactive elements that cause cancer. Sadly, the application of the noxious chemicals is done by farmers and/or sellers without the knowledge of innocent buyers and consumers who take fruits due to their nutritional values.

Many stakeholders have urged NAFDAC not to pay lip service to monitoring the quality of fruits sold to consumers as long as it falls under the agency’s statutory role. Some persons have also lamented that the agency has shifted so much attention to the war against fake drugs at the expense of food processing.

But some fruit sellers have argued that they have always followed certain safety processes while using carbide in the ripening of fruits. They maintain that they always have consumers’ safety in mind; therefore, they ensure that they do not expose the inner portion of the produce to the chemical.

“We make sure that there is no direct contact with the produce and the carbide and lastly all rotten, damaged products should never be sold to consumers but should be disposed of. I assure you that we always do our best to ensure that our members follow the recommendations by government regulatory agencies,” a seller said.

Related News

NAFDAC warns

Countering the fruit sellers’ claim, in July 2018, NAFDAC announced that carbide-ripened fruits could kill. In a statement, the agency’s Director-General, Prof. Moji Adeyeye, said the consumption of such fruits could lead to several diseases, including cancer, and death.

The agency added that fruits ripened with carbide lack nutrients, and were poisonous.

The statement read in part: “The consumption of fruits such as mango, banana, plantain, cashew, orange, grape, etc. or any other fruits ripened with calcium carbide is dangerous to health,”

NAFDAC, while warning traders and farmers against using carbide to ripen it fruits, said it would continue to carry out a nationwide monitoring of fruits markets to check activities of unscrupulous traders involved in illegal artificial ripening of fruits in order to ensure that such products were not sold to consumers.

Issuing the warning , Prof Adeyeye said ripening fruits with calcium carbide was not only dangerous to health but a criminal offence, and vowed that perpetrators would be prosecuted

According to the statement, the effect of artificial ripening on fruit quality affects properties such as colour, taste and feel, which are lost considerably and it does not give the natural aroma and flavour to the fruits.

“These fruits although possess uniform colour are less juicy than when ripened naturally and have comparatively shorter shelf life. Artificially ripened fruits may be ripe on the skin while the inside is unripe. If the fruits are all yellow whereas the stem is dark, the fruit may be identified as artificially ripened; this is true especially with banana and plantain.”

Highlighting health hazards of consuming fruits ripened with calcium carbide, the agency noted: “Calcium carbide when sprayed with water reacts chemically to produce acetylene, which acts like ethylene and ripens fruits by a similar process.

“These impurities may cause serious health problems when those applying calcium carbide on fruits come in direct contact with the chemical. Consumption of fruits containing these impurities may cause cancer, heart, kidney and liver failure.

“They may cause frequent thirst, irritation in mouth and nose, weakness, permanent skin damage, difficulty in swallowing, vomiting, skin ulcer and so forth. Higher exposure may cause undesired fluid build-up in lungs (pulmonary oedema).”

The agency warned that acetylene produced by calcium carbide affects the neurological system and reduces oxygen supply to the brain and further induces prolonged hypoxia.

NAFDAC said: “The impurities are hazardous to pregnant women and children and may lead to headache, dizziness, mood disturbances, mental confusion, memory loss, cerebral oedema (swelling in the brain caused by excessive fluids), sleepiness, seizure etc.

“Calcium carbide is alkaline in nature and erodes the mucosal tissue in the abdominal region and disrupts intestinal functions. Consuming such artificially ripened fruits could result in sleeping disorders, mouth ulcers, skin rashes and kidney problems.

“Other symptoms of poisoning include diarrhoea (with or without blood), burning or tingling sensation in abdomen and chest difficulty in swallowing, irritation in eyes/skin, sore throat, cough, shortness in breathing, numbness and so on.”

Side effects of consuming carbide-ripened fruits

While there are several causes of diarrhoea, experts have said it is one of the common presenting symptoms of consumption of carbide-ripened fruits. Others include burning sensation or tingling sensation in the abdominal region, difficulty in swallowing, irritation of the eyes, skin, sore throat, cough, memory loss, mood disturbances, mental distortion, shortness of breath and numbness.

According to Temitope, the reason the process is dangerous to health is the usual presence, in calcium carbide, of high level of impurities such as arsenic, lead particles and phosphorus etc. These impurities, he said, could cause cancer, heart, kidney and liver failure.

He added that they could as well trigger frequent thirst, irritation in the mouth, nose, and vomiting, skin ulcer in some case, among others.

“It should be noted that high exposure may cause undesired fluid retention in the lungs. Acetylene produced by calcium carbide affects the neurological system and reduces oxygen supply to the brain and further induces prolonged hypoxia.”

NAFDAC affirmed that eating them could trigger symptoms, such as diarrhoea (with or without blood), a burning or tingling sensation in the abdomen and others.

On how long it takes for reaction to begin to manifest in the human body after consumption, Temitope said the effects of chemical on the body varies from one person to another.

He explained that it affects the immune system, while over a long time, other reactions will be determined  by the amount of the fruit consumed.

He stated that the best way to ascertain people affected with consumption of carbide is through their blood levels if such persons go for tests, especially when a case of food poisoning is suspected.

How to identify artificially ripened fruits

It could be hard to figure out, but it is actually easy to know which fruit has been artificially ripened. One of the quick ways to identify artificial ripened fruit is to carefully observe the variation of colour. If the fruit is too good among others in “near perfect” ripening colour, it may have been ripened with calcium carbide.

NAFDAC agrees with this tip on identifying artificially ripened fruits. It advised consumers to examine fruits carefully by observing the variation of colour.

“If the fruit that you buy is too good among others in ‘near perfect’ ripening colour, it may have been ripened with calcium carbide. Fruits should be washed thoroughly under running water before consumption,” NAFDAC stated.

It has been discovered that the texture of fruits ripened with carbide is hard – even when it appears yellow, but when touched, it is hard, while the one ripened naturally has soft texture. Also, the conversion of starch to sugar in natural ripening is lost, therefore, loses its original fruit taste.

For fruits that were not mature before they were plucked, when it is dropped in water,  it will float, in contrast to naturally ripened ones, which will sink to the bottom of the water.