Vegetable growers have been using toxic chemicals to speed up growth and keep away pests that may cause serious health problems for the people, officials said.

High levels of pesticide residues have been found in five vegetable items sold in the Kathmandu Valley, a lab test conducted at the Kalimati Fruits and Vegetable Market showed.

The lab restarted rapid bioassay testing of pesticide residues in vegetables and fruits from mid-June after the government relaxed the lockdown restrictions.

Tests of tomato, cauliflower, eggplant, black eye bean and sponge gourd conducted between mid-June and mid-July showed a high concentration of harmful chemicals.

Prakash Ghimire, plant protection officer at the lab, said that samples of tomato from Kabhre and eggplant from Gorkha were tested with a pesticide of the organophosphate group ranging between 35-45 percent which can be consumable after keeping it for at least two days. But they were bought in the market without fulfilling the waiting period requirement, he said.

Similarly, cauliflower from Kathmandu and black eye beans from Dhading were also tested for high concentration of pesticide residue under the organophosphate group exceeding more than 45 percent. The vegetable was found to be not consumable and was dumped, he said.

Sponge gourd supplied from Chitwan also measured pesticides under the organophosphate group with a level between 35-45 percent, but it is consumable only after keeping for two days.

Unless the indicators do not show a green light, the vegetables do not get released in the market. Any vegetable with a pesticide level exceeding 45 percent is dumped, he said.

According to Ghimire, carbamate and organophosphate pesticides are highly harmful to human health and the environment. “These pesticides are neurotoxic and have an effect on the nervous system,” he said. Most of the vegetables sold at the Kalimati Fruits and Vegetable Market are grown using organophosphate rather than carbamate.

“Most of the pesticides under the organophosphate group have been banned by 50-60 percent in the country,” he said. But as the pesticide is easily accessible at any agro vet across the country, most farmers have been using it, due to which its presence has been seen in vegetables, he added.

“As newly arrived pesticides are available in the valley or at a few agro vets, farmers have been using organophosphate to save their crops from insects,” he said.

A combination of chlorpyrifos and cypermethrin pesticide under the organophosphate group is being widely used by farmers, he said. The use of pesticides under the organophosphate group is declining, according to the annual data being collected since the establishment of the lab, but farmers have almost stopped using carbamate due to its negative impact on the soil, he said.

The Rapid Bioassay Pesticide Residue lab at Kalimati has been testing carbamate and organophosphate pesticides. The test kit is easily accessible, and due to lack of manpower, the lab has been doing tests of only two types of pesticides since the establishment of the lab, he said. The lab has been regularly taking 10 samples of vegetables arriving at the market, he said.

Most of the vegetables sold in Kalimati come from Kabhre, Sarlahi, Bara, Chitwan and Dhading. Among them, vegetables from Kabhre and Dhading are found to have a high presence of pesticides, he said.

Ghimire said that he had been discussing with the Central Agriculture Laboratory and Ministry of Agriculture and Livestock Development to extend pesticide tests and add manpower accordingly. The ministry seems to be positive in this regard, he added.

As the lab remained closed for around three months during the lockdown period, no test was conducted and consumers were buying untested vegetables from the market. But Ghimire said that as agro vets also remained closed during the lockdown and the supply chain also got broken for a certain period of time, there was less chance of vegetables being contaminated with pesticides.

Pesticides are commonly used to get rid of insects, fungi, weeds and diseases, which damage plants and crops. Every year, more than 635 tons of 170 types of pesticides including insecticide, fungicide, herbicide and biopesticide are brought into Nepal, according to the Plant Protection Directorate of the ministry.

Facilities run by the Central Agriculture Laboratory have been regularly carrying out pesticide tests on vegetables and fruits brought into the Kathmandu Valley for sale. The agriculture laboratory has been operating rapid bioassay of pesticide residue labs in the country's seven provinces.