City dwellers have been facing severe mosquito problems for the last couple of months. Be it the posh areas of Dhaka City or dingy slums, the mosquito menace is overwhelmingly present everywhere. To get rid of mosquitos, people are buying coils, aerosols, mosquito repelling sprays and special mosquito nets infused with insecticide.
Moreover, the Health Division, city corporations, and municipalities are conducting regular mosquito control raids and spraying insecticide with fogger machines in various parts of the city. Despite all of these attempts, the mosquito problem seems to be out of control. To add to the worry, chemicals used in the insecticide and other mosquito repelling products are causing irreversible harm to human health. According to experts, the chemicals in aerosols, insecticides, and other mosquito control products are causing various diseases such as asthma, cancer, lung disease, kidney disease, etc. The substandard quality and unregulated use of these products are further compounding the problem.
Professor ABM Faruk of the Medicine Technology Department of Dhaka University said, “Permethrin is considered to be one of the best insecticides to kill mosquitos. If used properly, it does not cause serious damage to the environment or human health. However, in our country, Permethrin is not being used properly. Users are not maintaining the safe limit of doses and applying much more than what is needed. All the other medicines and repellents are already quite harmful to human health. Their toxic elements directly affect the lungs, liver, and kidney. While the toxic elements work their way through the adult human body over time, children quickly become ill because of them.” Dr. Rafiqul Islam, professor and former chairman of the department of Applied Chemistry & Chemical Engineering, University of Dhaka said, “Contact with large quantities of toxic components used in pesticides can lead to major health complications and harm the environment. These pesticides easily mix with water.”
Specialists said the World Health Organization (WHO) has given specific instructions about keeping the level of active ingredients in mosquito coils within .03 percent. This amount is enough to repel mosqui- MOSQUITO tos without risking health problems. However, coils and aerosols available in our market are capable of killing other insects, cockroaches, and even lizards, which proves they contain a much higher amount of active ingredients than the safety limit. Professor Benazir Ahmed, head of Parasitology at the National Institute of Preventive and Social Medicine (NIPSOM) and Former Director of the Disease Control department of the Health Division, said, “There will always be some harmful effect of mosquito repellent products. The smoke from the mosquito repelling coils damages the nasal passages, throat and lungs, and increases the risk of cancer. The aerosols are just as toxic, if not more. Long-term use of these products can cause serious, life-threatening diseases. Most people in our country do not read the instructions about using these products safely. As a result, the health and environmental risks are increasing.”
The Plant Protection wing of the agriculture extension department under the Ministry of Agriculture is in charge of issuing licenses for all pesticides, coils, sprays, and mosquito repellents. According to them, 77 local companies are either producing or importing over 500 brands of mosquito repellent products. There are different types of repellents for different types of mosquitos. The most used repellents are larvicide and adulticide. Permethrin, Allethrin, D-trans Allethrin, Tetramethrin, Deltamethrin, Biolethrin, Metofluthrin, Cypermethrin, Imiprothrin, Diazinon, etc., are just some of the chemicals used as mosquito repellents. While some of the companies use only one ingredient in the repellents, some choose to combine multiple ingredients.
Mohammad Golam Maruf, director of the Plant Protection wing, said, “Considering the harmful impact of mosquito repellents, we are taking many special preventive measures. As part of that process, we have banned the import of any type of ready to use repellents. We only issue licenses to import ingredients, but the final product must be produced locally. At the same time, we keep a watchful eye on the license holders to ensure they are following WHO guidelines. If somebody breaches those directions, we often take legal action against them. However, end users have to be cautious about this issue as well. They have to read the instructions before using the products. Counterfeit products cause more damage than regular repellents. So, the users have to be aware about buying authentic products.” The mosquito menace has made its way to the national parliament as well. Recently, Moinuddin Khan Badal, MP, said in parliament, “I could not sleep last night because of constant mosquito bites. When I sprayed the aerosol, the mosquitoswere knocked off for a short time, but they soon recovered and started biting again. I am bringing this issue to the parliament's attention so that more investigation and research can be conducted to solve this problem.”
In the advertisements, most aerosols and coils claim to have 100 percent mosquito-repelling power, which is not necessarily a good thing. Dr. Mahbub M Rahman, professor of the Entomology Department at Dhaka University said, “According to integrated pest management theories and the directives of WHO, a repellent that can kill 100 percent of mosquitos is very dangerous, and should be avoided. These repellents not only harm human health but also endanger other insects dependent on mosquitos.” Along with the authorized repellents, counterfeit and unauthorized pesticides are readily available in the market. The administration is frequently conducting raids to seize these products, but the market is being restocked quickly. Recently, speaking at a seminar titled “Unlicensed mosquito coils are ruining public health”, at the CIRDAP auditorium, information minister Hasanul Haq Inu focused on this issue. He said, “The unlicensed coil factories have to be shut down in order to protect people’s health. If the mosquito breeding sources can be controlled, the overall problem will be under control as well. Mosquito coil is an insecticide, so the producing companies must have approval from the Bangladesh Standards and Testing Institution (BSTI) or WHO before production.” “Mosquitos can spread many harmful diseases, but the coils can be just as harmful,” he added.
Other speakers at the seminar said that the unauthorized coils use a dangerous amount of active ingredients, which can cause serious ailments. Frequent use can lead to cancer, respiratory inflammation, etc. These ingredients are especially harmful for pregnant women, and their unborn babies. Just like formalin in food and arsenic in water, the toxic elements in these coils build up inside the human body slowly and have a long lasting effect. Research conducted by the Chest Research Foundation (CRF) in India found that the substandard mosquito coils contain cancer causing elements. Quoting the director of the foundation, Dr. Sandeep Salvi, a report said that the smoke emitted from one mosquito repellent coil in a closed room is equivalent to that of 100 cigarettes. The foundation conducted a research in 22 villages in Pune. The research found that 65 percent of the households keep both doors and windows closed while using mosquito coils, which accentuates the effect of inhaling toxic fumes.
According to another Indian research report, long-term use of mosquito repellent coils increases the chance of lung cancer by 40 percent. The miniscule particles of coils deposit in the airway and lungs and gradually cause damage. Long-term use also harms the eyes and increases the risk of cardiovascular diseases. All the coils contain Allethrin, which damages the regular function of blood and brain. Bangladesh is yet to conduct any similar research. Specialists said the use of insecticide- treated mosquito nets in the Hill Tracts is raising a major health concern. A banned pesticide is frequently being used to control malaria in those areas. The pesticide named KO-Tab 123 is being bought with government funding and applied to the mosquito nets of residents in the malaria-prone areas. The government’s long standing national malaria control program is distributing the insecticide and insecticide-infused mosquito nets among people. However, there are some concerns about the effects and effectiveness of these repellents. It has been said that malaria carrying mosquitos have already developed immunity against these insecticides, although human health is still being damaged.
The Plant Protection wing sources said that KO-Tab 123 is yet to be authorized for mass use. In some areas of the CHT, mosquito nets containing a high amount of this insecticide are being used indiscriminately. Some people are allegedly using these mosquito nets to catch shrimp from Kaptai Lake, while some are even using it in cultivable lands. An expert from the Health Division said that insecticide-infused mosquito nets are supposed to be used with great care. These nets are not supposed to be directly washed in ponds or rivers. The insecticide used in these nets is harmful for fish. However, most users are not paying any attention to these issues. As a result, this insecticide is posing a great threat to human health and the environment. There is no effective monitoring system to prevent this indiscriminate use of insecticides, he added.