Apart from the pervasive adulteration of food, excessive use of pesticides, often of below par quality, in the cultivation phase poses serious threats to human health.

A new study finds that almost one-third of the pesticides used in farming vegetables and fruits in the country are substandard.

This is forcing farmers to apply excessive doses of pesticides that, experts say, not only raises the production cost but also causes grave health hazards to consumers in the long run.

Worse still, the overdosing of these subpar chemicals is strengthening resistance in the insects, which means standard doses cannot kill them in many cases.

The monitoring authorities admit the fact and claim they were doing their part to maintain pesticide standards. Food safety activists, however, say monitoring at the field level is weak and must be intensified to ensure both quality and proper doses of pesticides.

THE RESEARCH

For the study, Bangladesh Agricultural Research Institute (BARI) collected 32 pesticide samples of different brands.

After testing them, it found 30 percent of the pesticides contained active or key ingredients of half the prescribed quantity.

"The findings indicate a lot about the overall standard of pesticides," said Dr Monirul Islam, director (nutrition) of Bangladesh Agricultural Research Council (BARC), who coordinated the study released last July.

The research, commissioned and published by the BARC, also says that due to the diminished impact of the pesticides, farmers now have to use pesticides 10-15 times the prescribed amount for producing fruits and 8-10 times for growing vegetables.

Read all stories of our "Speak Out for Safe Food" series below-

• HARDLY ANYTHING SAFE TO EAT
• Profit, more profit
• PESTICIDES USEd 15 times the limit
• Old formalin in new bottle
• ILLEGAL, HARMFUL
• Confusing battle fought so far
• Too many cooks spoil the broth
• Evil rules as state sleeps
• Cold chain can save food supply chain
• Poisoning Poultry, Fish
• Green initiative left in the lurch

The truth of this was found in what Tariqul Islam, a farmer from Kodalia of Jessore Sadar, said: "About 10 years ago, we used to apply pesticides once a month or sometimes twice. But now many of us have to apply it every week, and even twice or thrice a week in some cases."

"I know of some incidents in which agriculture officials prescribed a particular pesticide but it did not work. Then farmers mixed two or three different pesticides and sprayed the mixture on vegetables," he told The Daily Star over the phone.

BARI Director General Dr Rafiqul Islam Mondal said while adulteration could be a reason behind the excessive use of pesticides, many farmers did not know the right doses either.

Farmers' awareness of a proper application of pesticides is crucial in checking extensive use of these toxic chemicals, he added.

THE PERILS

Ataur Rahman Milton, member of Bangladesh Food Safety Network (BFSN) that closely works with farmers, said the use of substandard pesticide raises production cost.

"If a farmer needed Tk 50 for pesticides earlier, he now needs Tk 500 for the same. And the additional cost is passed on to the consumers," he said. Naturally, more use of pesticides means more business for the marketing companies.

Professor Mahmudur Rahman, director at the Institute of Epidemiology, Disease Control & Research, says due to the overdose of pesticides, the produce may retain toxicity even after harvest. And exposure to or consumption of these fruits and vegetables may even lead to death.

"Initially, mild symptoms like headache and nausea are experienced," he said. But in the long run, it can affect the kidney and liver as well.

There's more.

According to the US Environment Protection Agency, excessive use of pesticides can affect the nervous system, irritate the skin or eyes and cause cancer and even hormonal damage.

"Pesticide residues remain in the soil and air for many years. If applied excessively, these can affect human health for generations," Prof Rahman said.

However, Rafiqul Islam Mondal of BARI said the effects can be minimised if farmers stop spraying pesticides at least a week before the harvest.

THE BLAME GAME

Rafiqul Islam, former secretary general of Bangladesh Crop Protection Association (BCPA), an organisation of pesticide companies, admits the fact of adulteration of pesticides, but puts the blame on small traders.

"Big companies cannot adulterate pesticides … because if it's detected, their reputation will be at stake," he said.

But small traders say otherwise.

Mustafizur Rahman, owner of Classic Agrovet Ltd, a small pesticide company in Dhaka, thinks an adulterator can be any company -- big or small.

"We have recently seen that a big company was found manufacturing adulterated consumer products," he said, without naming the company.

Ketabur Rahman, a pesticide retailer of Bholahat upazila in mango-rich Chapainawabganj, said there's no chance of tampering with pesticides at their level.

"We deal with the farmers directly. If their produce is affected by any of the pesticides we sell, farmers won't let us get away with it," he told The Daily Star over the phone.

However, both sides agree on one thing: the government should strengthen its monitoring mechanism.

There are nearly 400 companies, which import and market about 37,000 tonnes of pesticides annually, but only some 200 are members of the BCPA, Rafiqul Islam said.

There are companies that are not registered even with the Department of Agriculture Extension's Plant Protection Wing (PPW), which regulates the pesticide business, he went on.

Though the government has made it mandatory for pesticide traders to be members of the BCPA, the responses are weak. It proves the government's monitoring mechanism is feeble, he added.

THE REBUTTAL

Rejecting the traders' allegations, Shah Alam, deputy director (pesticide) of the PPW, said they regularly monitor pesticide quality.

There's a Pesticide Testing Advisory Committee comprising entomologists and agriculturists who conduct laboratory and field tests before approving the import and marketing of a pesticide, he said.

Also, the PPW randomly tests pesticide samples every month. If found to be adulterated, pesticides of the batch concerned are cancelled and withdrawn from the market, he said.

Twelve types of pesticides were banned and destroyed in 2013-14 for their substandard quality, Shah Alam added.

The Pesticides Act (Amendment) 2010 has a provision of up to two years' imprisonment and cancellation of licences for adulteration of pesticides.

On unregistered traders, he said if they have information, actions are taken against such companies. Three unregistered traders were sued in the last fiscal year.

Ataur Rahman of the BFSN, however, commented that agriculture officers at the field levels were negligent in monitoring the quality and quantity of chemical inputs.

"Food safety has become a serious public health concern. So, it is time that we shifted towards natural pest control mechanisms. And, in the meantime, quality of pesticides must be checked properly to ensure safer products for consumers," Rahman concluded.