Sweet poison: illegal ripening of fruits exposes millions of Kenyans to cancer

Fruits in APMC market, Maharashtra state, India. Calcium carbide use is rampant in India
Fruits in APMC market, Maharashtra state, India. Calcium carbide use is rampant in India

In an investigation in Kenya and India, writer Kiprotich Koros, discovers how corrupt businessmen use cancer-causing chemicals to ripen fruits. Officials now warn millions of people risk early grave by eating fruits laced with these chemicals.

An investigations in the past one month has unearthed rampant use of calcium carbide - an artificial ripening agent - by unscrupulous traders and supermarkets in Nairobi and Mombasa.

The chemical is used to hasten ripening of bananas, mangoes and apples for sale to millions of Kenyans. The chemical uniformly ripens fruits making them desirable to customers.

Samples taken from three leading supermarkets and groceries in Nairobi and Mombasa tested positive for the poisonous chemical used for welding and for making plastics.

Wholesale traders in big fruit markets in Gikomba, Nairobi, Marikiti and Kongowea in Mombasa are using the chemical secretly.

Fruit adulterated with calcium carbide may also be finding their way to Kenya from other parts of the world as there are no laws governing its use. The Pesticide Product Control Board (PPCB), Kenya Bureau of Standards (KEBS), Government Chemist and Kenya Agricultural Research Institute (KARI) are unable to test for the chemical as they did not have the necessary equipment or protocols.

Despite the serious health risks it poses, it is not listed by the Pesticides Control Products Board (PCPB) as a banned substance.

Some of the mangoes, bananas, oranges and apples in the Kenyan market are imported from Tanzania, Uganda, South Africa, Egypt and as a far as India where calcium carbide use is rampant.

This raises major public health concerns with the steep rise of cancer cases in the country over the past few years.

Cancer is the third killer disease in Kenya. According to the Nairobi Cancer Registry, 38,544 new cancer cases were diagnosed in 2012 with 26,941 deaths occuring in the same year.

The Cabinet Secretary for Health, James Macharia, has termed the cancer menace alarming.

Calcium carbide is used in producing acetylene gas employed in welding and the making of plastics.

"The chemical contains arsenic and phosphorous impurities which can cause other serious commplications including miscarriage in pregnant women, liver and kidney damage," says Dr. Daniel Sila, a Food Science and Technology lecturer at Jomo Kenyatta University of Agriculture and Technology (JKUAT).

Calcium carbide, when broken down, also contains phosphorus and arsenic compounds. This causes poisoning. Arsenic, for example, is highly carcinogenic. Skin damage also results from exposure to these two chemicals, he elaborates.

Calcium carbide, when broken down, also contains phosphorus and arsenic compounds. This causes poisoning. Arsenic for example is highly carcinogenic. Skin damage also results from exposure to these two chemicals, he elaborates.

“Calcium carbide produces a gas known as acetylene which has similar effects as ethylene - a natural ripening agent. Calcium carbide has been banned in many countries because of its effects including dizziness, mental confusion, vomiting. The reason for this is that acetylene deprives the brain of oxygen. This leads to a condition called hypoxia," says Dr Sila.

"The reduction of oxygen in the brain results in headache, dizziness and even result in brain breakdown since it needs oxygen to function.”

He adds: "Calcium carbide when broken down also contains phosphorus and arsenic compounds. This causes poisoning. Arsenic for example is highly carcinogenic. Skin damage also results from exposure to these two chemicals.”

But in an interview, Prof Fred Segor, Principal Secretary for Health, said he has not received any complant of any illegal chemical being used. "What is released in the market is within acceptable limits," he said.

Calcium carbide is banned in Asia, United States and for its harmful effects.

According to an official at the PPCB, chemicals are only listed under the banned list only if they had been previously allowed for use.

"Calcium carbide is prohibited in India under Food Safety and Standards Authority of India (FSSA) laws,” says Dr Mahesh Zagade, Food Commissioner, Food and Drug Administration, Maharashtra, Mumbai India.

The authority conducts frequent swoops on traders in major markets. Those found to be using the chemical are prosecuted and their fruits impounded. The authority also conducts sensitisation campaigns across the country on the dangers of using calcium carbide.

But authorities in Kenya seemed to be oblivious of the public health risk. Kenya does not have a law specifically prohibiting the use of calcium carbide in the country.

"Before any chemical is used it has to be approved. As of now I have not received any complaint concerning a chemical which is not supposed to be used," says Prof Segor.

There are also reports that food leaving the country for destinations like Europe and the US undergo more rigorous testing than those entering or distributed in Kenya.

"When the consumer complains, it is our responsibility to subscribe to what they want," he said referring to countries which import products from Kenya.

Before any chemical gets into the country, there is regulation even from the country which is exporting to Kenya. KEBS and KEPHIS just have a complementary role at the borders, says Prof Segor. “If they are unable to do a proper analysis, then they give it to our government chemist. We do not advice the importation of chemicals which we cannot detect,” he added.

In a statement, the National Environmental Authority (NEMA) which is charged with regulating industrial chemicals, said it is developing a legislation for registering hazardous chemicals.

It is however awaiting gazettement.

"Once gazzeted, the regulation will enhance compliance by regulated communities and enforcement actions by the Authority," the statement said.

Currently calcium carbide is used in industrial processes for manufacture of different commercial products. The chemical can cause human poisoning through ingestion, inhalation and dermal (skin) contact, the statement added.

The Material Safety Data Sheets (MSDS), an internationally recognized document, notes that calcium carbide is hazardous and poses serious risks to human health and environment if misused or not properly managed.

But the Government of India's account of its efforts to combat the use of calcium carbide was lambasted by traders in APMC market, Mumbai, one of the largest fruit and vegetable markets in Maharashtra state.

A trader claimed that the government encourages them to use the chemical to get ahead of the competition.

Some of the fruits sold in the Kenyan market come from India.

Alam Khan, one of the traders who spoke to this writer in India, described how they spike fruits with calcium carbide. He sells fruits at the market, in the outskirts of Mumbai.

"We wrap the substance (calcium carbide) in small paper packets, we then place it next to the pile of fruits. The fruit will be ripe within two days," he said. "Calcium carbide is very cheap. With about a hundred rupees, I can ripen about a tonne of fruit."

When exposed to moisture, calcium carbide produces acetylene gas which triggers the ripening process.

This could in part explain the presence of calcium carbide in some of the fruit tested during this investigation. India exports its mangoes and apples to Kenya and other destinations.

"We export the fruit to Kenya, Dubai, America, Japan, London, Saudi Arabia, Sudan, Indonesia and many other countries."

"We use calcium carbide on mangoes, apples, cherries, bananas and other fruits," said Alam.

Practice Catching On

But the practice seems to be catching on in Kenya as well.

We met Wasike at the busy Gikomba market in Nairobi. Wasike earns his living ripening bananas for wholesale store owners who sell the fruits to the millions of Nairobians.

He works for a businessman deep in the open air market. It has been raining and the roads are muddy with sewage and organic waste making a spongy carpet. His workstation is a dark room with large boxes of bananas stacked high into the roof.

Here he slices green avocados, which are then evenly spread with the green bananas before they are closed tightly with plastic bags. The bananas will usually ripen within three days, he says.

Wasike also works for another businessman in Eastleigh who exports fruit to Europe and America. "We stack piles of bananas and mangoes in a warehouse. We then wrap a small pellet of the chemical in a small paper and put it next to the pile. "Huwa zinaiva baada ya siku moja au mbili (The fruits usually ripen within one or two days),” he says.

Several officials lamented the poor state of labaratory equipment at various government institutions charged with ensuring the safety of Kenyans from exposure to dangerous agents.

Regulatory agencies like the Kenya Bureau of Standards and the Kenya Plant and Health Inspectorate are located at the port of Mombasa.

But according to a KEPHIS official who requested not to be named, the agency does not have the equipment necessary to test for calcium carbide. Instead the authority relies on declaration from the exporting country.

"Little is done to ensure food safety for food distributed in the country said the official. Regulatory authorities suffer from incoordination and there is little surveillance carried out on food being sold within the country. Most of them are made in very poor conditions and sometimes dangerous chemicals are used," he said.

“This issue of calcium carbide is of a great concern to us, but again it is very elusive,” says Dr Robert Kilonzo, Food Safety Officer at the Ministry of Health. There is part of the chain which is difficult to enter. We can only get what is placed in the market. Before being placed on the market, its very tricky,” implying the non-formal supply chains.

“Every trader wants to make quick money especially when demand is higher than the supply. The rush to make quick money is creating a lot of problems for us. Unfortunately according to our laws we do not have the residue levels. It (calcium carbide) is not supposed to be used because of the side effects. It is a criminal offense to use these chemicals,” he points out.

“The spectrum for fruits meant for export is quite big and such chemicals are likely to be detected, says Dr. Kilonzo. Our testing however has a limited scope, he admits. This is a new area and a new challenge to everybody,” he adds.

“The other challenge is the subsistence nature of our farming and trade where a farmer will plant and hawk his produce within his neighbourhood making it difficult for us to monitor.”

“Creation of awareness is the most important thing we can about this matter on what the chemical is what it can do to our health and how to notice it. This is the way to beat the crooks,” he notes.

It is this quality to ripen fruits faster that drives many traders to adulterate fruit. Artificially ripened fruit usually have an attractive uniform colour. The tissue inside may however be raw as the fruit is not usually mature. However, they develop black blotches and perish faster.

Mustafa sells his fruit from his stand to the thousands of customers who flood Marikiti market in Mombasa Mustafa. His brightly yellow bananas and mangoes easily catch the eye of many customers. "Business is good," he says.

He is supplied by a warehouse nearby where "mangoes and bananas are gassed," Mustafa says. "We know that the chemical is dangerous but we have to earn a living," Mustafa says.

A sample taken from the market had calcium carbide and arsenic residues. "Hapo zamani hawa wanabiashara wakubwa walikuwa wanaweka hiyo dawa hapo Mombasa grounds lakini sasa wamefukuzwa ( wholesale traders used to adulterate their fruit at Mombasa grounds but they have since been evicted by the city council)," he says.

Calcium carbide is hawked at the busy Gikomba market for as little as Sh20 a sachet. Bernard Mwangi, a hawker, buys his supplies from a wholesale shop in the city centre, repackages them into smaller packs and sells them to the many traders in the market. "A 25 kg bag costs about Sh3,000. “We repackage it to make more profit out of it,” he says.

"We believe that some of the diseases we see today is because action was not take 10 or 20 years ago to control the exposure of the population to the risk factors. We can invest today in prevention and save a lot of costs in future in treating people who are ill. The policy is being finalized and we expect it to be out soon," says Dr. William Maina, who formerly headed the Non Communicable Diseases Department at the Ministry of Health.

"The ministry has now put up a unit that will be looking at food safety and quality. The aim of this unit is to look at issues of food processing, food packaging and food production and to conduct post market survey of food out there in the market. The aim is to ensure that the food that people are getting out there is not a risk to their health. The unit will advice on the necessary health measures to be taken if any of samples is injurious to their health," Dr Maina says.

He adds: "We have also strengthened our labaratory back up for that. We have set up a specific lab that will look at food safety. They will analyze if there are any compounds in food that may be injurious to health, analyze and advice accordingly. The ministry currently plans to put in place legislation that controls the production, marketing and consumption of food that are a risk to health.”

Ripening is a natural process. Climacteric fruits like bananas have to ripen for them to have the quality for eating. This allows them to get the sugar, soften and get the aroma and even the colour. This happens in fruits like pawpaws, mangoes, and bananas.

Natural ripening is slow.

"If you are producing these fruit for the commercial market you need to have them ripen at the same time. Artificial ripening is done so that you can bring the fruit at the same state of ripeness for sale. Ripening needs a plant hormone called ethylene that is within these fruit. It is proper to allow our fruit to mature so that you get the right quality - the sugar level, aroma and the firmness. If you harvest a fruit which is not mature, it will ripen but it will not have the flavour or the good aroma. It also affects the nutritional value," says Dr. Margaret Muchui, Principal Research Officer at the Kenya Agricultural Research Institute (KARI).

"Certain twigs fruits like passion fruit are rich in ethylene and can be used safely to ripen fruits. This indigenous knowledge was used traditionally to ripen fruits," she says.

Safe ripening of fruits

Purple passion fruit, avocados and white sapote are very high in ethylene and can be used to safely ripen fruits she adds.

But there are also sophisticated methods where ethylene generators are used. Fruit is put in airtight rooms and the ethylene gas is injected. The chamber is ventilated after 24 hours for about 30 minutes to remove carbon dioxide because it anti-ripening.

"Calcium carbide should not be allowed to be used because it is dangerous. Calcium carbide combines with water to produce acetylene but it may have arsenic, phosphorous and may have carcinogenic material. Calcium carbide is easy to access and unscrupulous businessmen may use it to ripen fruit," warns Dr Muchui.

"However it is hard to know a fruit that has been ripened with calcium carbide and one that has been ripened using ethylene sources. We need to work with the regulatory agencies to stop it if it is happening," said the scientist.

But natural ripening also has to ripen within certain conditions and Dr Muchui advises traders to ripen between 16-18 degrees and a humidity of 90 to 95 per cent.

Kari has developed a ripening chamber where fruit can be ripened safely. Passion fruits or avocados are placed at the lowest shelf to produce ethylene gas. The fruit on the top shelves usually ripens within two days, says Dr. Muchui. The airtight chamber should however be ventilated after 24 hours for 30 minutes.

Only ethephone and etherel have been registered by the Pest Control Product Board for the ripening of fruits.

Banning Calcium Carbide is complicated

But banning calcium carbide use is difficult as it is registered for other legal uses, says Dr Jane Njiru, a scientist with the Pest Product Control Board.

"If people are diverting a product for other use other than the registered one, then it is treated as misuse. It is very difficult to ban a product because of misuse. We should sensitise people not to move products across markets from welding to crop use," she says.

"We should also ensure tighter controls so that there is accountability from people importing it for industrial use," Dr. Njiru suggests.

But is it possible to specifically ban calcium carbide use for ripening fruit while allowing it for other industrial uses?

No, says Dr. Njiru. That is not possible because we had not allowed it in the first place.

"This is a matter that we (PPCB) and other agencies like NEMA should take up." This is an industrial chemical and it is regulated by NEMA because they allow it to come in for welding purposes.

Ideally, imports should only be of registered products. This is enforced through import licenses. Importers have to declare their product with the PPCB. Occasionally containers are also opened for inspection, Dr. Njiru says.

In Kenya, cancer ranks third as a cause of third accounting for 7 per cent of national mortality. An estimated 22,000 people die each year from cancer. About 28,000 cases are reported annually. It is feared that the number is much higher as many cases are not reported or diagnosed. About 60 per cent of those affected are below 70 years. Exposure to environmental carcinogens, tobacco and alcohol abuse are cited are the major causes of cancer.

Cancer is projected to rise by 70 per cent by 2030 in middle income countries and by as much as 82 per cent in low income counntries if no action is taken to stem the menace. The economic loss in output from cancer is estimated at $70 trillion by 2025 in low and middle income countries.

The cost of treating cancer is prohibitive for most Kenyans with a session of chemotheraphy costing between Sh6,000 and Sh600,000. The side effects of treating cancer can also be debilitating.

Cancer is a major health challenge and it is projected that Africa will have 1.6 million cases by 2030 with 1.2 million deaths annually.

Identifying Artificially Ripened Fruit

You have probably peeled a uniformly yellow usually unblemished banana or mango only to find green raw tissue inside. This is just one of tell-tale signs of chemical ripening. Naturally ripened bananas for example are not uniformly yellow, they are green and yellow.

If the stem is dark green but the fruit is yellow, chances are high that it is artificially ripened. Uniformly red tomatoes or uniformly yellow or orange mangoes may also have been artificially ripened.

Avoid buying fruits with these eye catching uniform colours. Always wash and peel fruits before eating to reduce the chemical content on the skin. Experts also advise cutting fruits into pieces instead of consuming them directly.

Also avoid buying fruits which are off-season as they are more likely to have been artificially ripened.

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