Insect Spraying Pros and Cons

Published in Poisons Beware

For several years, the local councils of Jelsa, Stari Grad and Hvar have routinely sprayed the streets against mosquitoes, flies and other 'flying pests'. Is this a good thing?

Due warnings?

Bees, of course, are not among the targeted victims. When the spraying is due, beekeepers are routinely warned to close their hives. Over the years, I have found that very few beekeepers hear the warning, many don't heed it even if they do. Some have even told me that the spraying is "not very harmful" to bees.

The poisons used are said to be harmless to warm-blooded creatures. However, people with breathing problems are advised to stay inside and shut all windows and doors. Not much help to tourists staying in the campsites, nor to anyone on a night out when the spraying (known as 'fogging') starts at 22:00, finishing at 06:00 the next morning. When the spray-van passes up the road, it does not stop its poison-spreading to ask people if they are vulnerable to chest problems! As I experienced first-hand in 2012, to my dismay.

Although the sprayings take place during the summer season, they are only announced in Croatian. English-language websites, such as Total Hvar, are able to transmit them if they wish - if they happen to get the news in time. But at times the warning has been issued late. On occasion the spraying has happened earlier than the night advertised. In the past, notice was given in some local Council websites (notably Stari Grad's) and the local press. This year, there have been two sprayings to date just over a month apart - in late June and early August - with very little public notification.

Which poisons?

The names of the poisons used for the spraying are never publicly announced. Ekocijan, which covers Hvar, states on its website that its insecticides are "imported, environmentally friendly, biodegradable and harmless to warm-blooded creatures." But it stops short of naming them. After some research, I found that the Croatian Beekeepers' Association revealed in 2012 that on Hvar two pyrethroids, Cypermethrin and Permethrin, were being used in combination as the basis for the poisoning. In 2014, a product called Permex 22E was used, a combination of Permethrin with another pyrethroid, Tetramethrin.

According to the American Environmental Protection Agency (EPA), Pyrethroids are "synthetic chemical insecticides". They should not be confused with Pyrethrins, which are botanical insecticides derived from the pyrethrum flower, a type of chrysanthemum called buhać in Croatian. The chemical structure of Pyrethroids is based on that of Pyrethrins, but there are significant differences in the way the two insecticides are formulated as preparations for use.

Pyrethroid effects

Pyrethroid insecticides act on the target's nervous system, causing paralysis and death. Apart from killing mosquitoes, Cypermethrin is highly toxic to bees, water insects and fish, less so to birds. In humans, Cypermethrin poisoning can cause numbness, burning, loss of bladder control, vomiting, loss of co-ordination, coma, seizures, and death. It is also classified in the United States as a possible cause of cancer. Permethrin comes in different formulations, some more toxic than others. It is highly toxic to bees, aquatic life, fish and other wildlife. It is also toxic to cats. Its possible effects on humans are considered less dramatic than those of Cypermethrin, but it can affect the immune and endocrine systems. The EPA rates it as possibly carcinogenic. In view of their damaging effects on aquatic life, pyrethroids should not be applied near water sources - which are of course the breeding grounds for mosquitoes. Permethrin is not supposed to be sprayed where animals might forage. The EPA re-registration document for Tetramethrin (2010) classified the poison as a possible human carcinogen, and identified it as highly toxic to bees and aquatic organisms including fish and aquatic invertebrates. It can cause dizziness, breathing difficulties, coughing, eye irritation, gastrointestinal upset, blisters and skin rashes. The EPA document stated that: "Tetramethrin is used by individual homeowners or industrial / commercial property owners, in individual, isolated areas, and in small amounts as opposed to wide scale uses (i.e., for agriculture or mosquito abatement by public authorities)." For this reason, they did not test the effect of Tetramethrin on drinking water. Tetramethrin is not supposed to be used on or near foodstuffs.

Croatia and insect control

Croatia's Law for Protecting the Population Against Infectious Diseases (Zakon o zaštiti pučanstva od zaraznih bolesti) holds that controlling harmful insect populations through mechanical, physical, biological or chemical means is a general measure for preventing and controlling infectious diseases (Article 10). In practice, the most frequently used method is spraying with chemical poisons, as happens on Hvar. Local Councils are responsible for organizing the spraying, although apparentty some have failed to do so because of lack of funds. In 2014, the Croatian Parliament debated bringing in fines for authorities who did not undertake anti-insect measures.

Why anti-insect measures?

The Croatian Association for Disinfection and Control of Insects and Vermin (Hrvatska udruga za dezinfekciju, dezinksekciju i deratizaciju - HUDD), which collaborates with the Croatian Public Health Authority, has issued a leaflet for the public outlining measures of control by individuals as well as professional organizations. The leaflet describes the sins of the mosquitoes: "they can spread infectious diseases; their bites cause significant skin problems; they are a nuisance in relation to normal human activities; and when there are a lot of mosquitoes, they collectively cause dissatisfaction among citizens and tourists" - this last 'mosquito crime' is given special emphasis with bold enlarged type.

There is no doubt that mosquitoes can cause serious diseases. Historically, tropical countries were those worst affected, but there has been a steady spread around other countries, and in recent years mosquito-borne diseases have been surfacing in Europe. Despite the fact that thousands of people are bitten every day by mosquitoes and other insects in Europe, there has been no epidemic of these diseases. In Croatia, there were four cases of West Nile Virus in horses between 2001 and 2002, and two cases of Dengue fever in humans confirmed in 2010. There was a large outbreak of Dengue fever on the Portuguese island of Madeira at the end of 2012, totalling over 2,000 cases, without any reported deaths. The World Health Organization (WHO) estimated in 2014 that there were about 500,000 cases of severe Dengue infection worldwide each year, of which about 2.5% (12,500) die, whereas tobacco causes about 6 million premature deaths each year, including more than 600,000 due to second-hand smoke. (These figures have increased since then.)

Does anti-insect spraying work?

In early 2014, it was reported that the authorities in Osijek in northeastern Croatia were complaining that their efforts at controlling mosquitoes through spraying were undermined by invasions from neighbouring areas which were not using insect control measures. The Croatian government allocated 5 million kunas (654,000 euros, £518,000) to Osijek for the war against mosquitoes, with a further 4.5 million kunas (588,000 euros, £466,000) due from the city budget. These are very large sums in terms of the Croatian economy. Presumably similar incentives will be given to neighbouring regions to carry out anti-insect measures.

On Hvar, anti-mosquito spraying has been carried out at least twice annually for some years. In that time, the mosquito infestations have become noticeably worse. As I write, a few days after the latest spraying, tiger mosquitoes are gliding around in a little silent horde, at intervals feasting on the exposed parts of my arms and legs. During the evening and overnight, the tiger mosquitoes' noisy buzzing cousins take over. Most people on Hvar agree that the immedtiate effect of the spraying is to make the mosquitoes angry and more ferocious, but there's no evidence of the numbers reducing, quite the contrary.

The principle of fighting a war to kill off all the 'enemies' is faulty in every context. Our civilization has arguably been more successful in driving towards extinction species which in fact we want to preserve than in exterminating perceived threats to our wellbeing, whether bacteria, terrorists - or insects. There is a strong body of opinion against spraying poisons to control mosquitoes.   For instance, writing for the Environmental Association of Nova Scotia (EHANS), Canadian Rebecca Watson outlined the reasons why spraying is not the solution to potential diseases like West Nile Fever. It is said that insect control spraying can be relatively successful in the short term, if it is properly planned, targeted and timed. But even then, the use of poisons invariably leads to resistance in the target species, as happened when DDT was used in large quantities against malarial mosquitoes in the 1940s and 50s. Poisons also cause collateral damage, often reducing the target insects' natural predators, not to mention essential insects such as bees. 

Non-chemical methods of insect control

While spraying is widely used, there is debate over the best way to control disease-carrying mosquitoes. Methods other than chemical spraying are being developed. These include genetic control, which consists either of suppressing mosquito populations by introducing genetically modified mosquitoes with a lethal gene so that when they mate with wild mosquitoes they do not produce young, or of replacing the wild populations with GM mosquitoes which are less potent disease carriers. This method has been effective in reducing carrier mosquito populations, but there are question marks over its safety if the GE mosquitoes infect human blood.

Biological control consists of using natural predators to prevent mosquito populations from multiplying, such as mosquitofish (Gambusia affinis) and frogs. A variation is the Sterile Insect Technique (SIT), in which male mosquitoes sterilized by irradiation are released into the wild to mate with females. This reduces the targeted mosquito population as any offspring produced cannot survive to adulthood. One of the most promising alternatives to straightforward chemical methods of controlling mosquitoes is said to be the use of the bacterium Bacillus thuringiensis (Bt). However, even this has been found to have unwanted effects, possibly reducing biodeversity and affecting reproduction in birds.

Positive thinking

It is very easy to panic about the possibility of 'deadly diseases' smiting human populations. Outbreaks and epidemics are frightening events. Preventing diseases is complex. A lot depends on the conditions in which people live: worldwide, good health depends on clean water, a healthy environment, a safe food supply and pure air, to name but a few. Lifestyle habits also play their part in strengthening or undermining the human immune system, which is key to avoiding disease or being able to recover if an illness is contracted. Mortal enemies to good health are smoking, excess alcohol, over-eating unhealthy foods, under-eating and insufficient exercise.

There are practical measures which individuals can take to reduce the risks and nuisance from mosquitoes. Using citronella candles or electronic 'bug-zappers' can keep the numbers in your immediate vicinity down. Mosquito nets over windows can help prevent them from entering your environment. Bites can be soothed by plant-based creams such as Arnica. I mentioned that I am being bitten as I write: when I was young, I suffered strong reactions to mosquito bites, but in later years this ceased, for a number of reasons. One of my preventive measures is to take a vitamin B complex supplement, having read that it would help the problem. For me, it works. Dealing with life's challenges is individual, and every reasoning person should be free to choose his or her own way. 

Some, probably many of us want to avoid contact with poisons as far as possible in our lives. At present, on Hvar and elsewhere in Croatia, that freedom of choice has been removed. It's time to scrutinize the use of poisons in the environment and to understand how dangerous they are for the health of present and future generations. Non-toxic methods of dealing with potentially harmful creatures must be used in place of the chemical poisons which cause mass destruction of vital natural resources.

URGENT ACTION IS NEEDED!

© Vivian Grisogono 2014, updated 2016, 2017

POSTSCRIPT: The tragic case of Bobi, the dog who didn't need to die, has highlighted that in 2017, three years on from when this article was first written, the practice of large-scale insecticide spraying or 'fogging' on Hvar has gone from bad to worse. Four toxic chemicals in a lethal cocktail, sprayed round the streets with minimum warning: how can anyone justify that?

Comment with a useful link from the USA:
"Saw your article. Agree wholeheartedly. 
Indiscriminate spraying like Ekocijan does has been discontinued virtually everywhere in the civilized world.
Here for example is a paper from the US CDC http://wwwnc.cdc.gov/eid/article/7/1/70-0017_article
But I guess someone is making a nice living and does not feel the need for change..." Zdravko Podolski, August 7th 2014
 
Tips: Citronella oil, a natural insect repellent, and more

Media

You are here: Home poisons be aware Insect Spraying Pros and Cons

Eco Environment News feeds

  • Report looks at 16 conflict areas and calls for military to stop targeting water resources

    Diarrhoea and other diseases related to poor sanitation are bigger killers of children in areas of conflict than violence and war itself, a report has found, highlighting the need for improved infrastructure as a way of helping civilian populations afflicted by warfare.

    Children under five are more than 20 times more likely to die from diarrhoeal diseases than from direct violence, according to Unicef. Henrietta Fore, the organisation’s executive director, said: “The reality is there are more children who die from lack of access to safe water than by bullets.”

    Continue reading...

  • Failure to protect wildlife, cut pollution and increase funding have left nature in ‘deep crisis’

    The UK will miss almost all the 2020 nature targets it signed up to a decade ago, according to a report by the government’s official advisers.

    The nation is failing to protect threatened species; end the degradation of land; reduce agricultural pollution; and increase funding for green schemes, the assessment concludes. It also says the UK is not ending unsustainable fishing; stopping the arrival of invasive alien species; nor raising public awareness of the importance of biodiversity.

    Continue reading...

  • The ‘Dieselgate’ scandal was suppressed for years – while we should have been driving electric cars. By Beth Gardiner

    John German had not been looking to make a splash when he commissioned an examination of pollution from diesel cars back in 2013. The exam compared what came out of their exhaust pipes, during the lab tests that were required by law, with emissions on the road under real driving conditions. German and his colleagues at the International Council on Clean Transportation (ICCT) in the US just wanted to tie up the last loose ends in a big report, and thought the research would give them something positive to say about diesel. They might even be able to offer tips to Europe from the US’s experience in getting the dirty fuel to run a little cleaner.

    But that was not how it turned out. They chose a Volkswagen Jetta as their first test subject, and a VW Passat next. Regulators in California agreed to do the routine certification test for them, and the council hired researchers from West Virginia University to then drive the same cars through cities, along highways and into the mountains, using equipment that tests emissions straight from the cars’ exhausts.

    Continue reading...

  • Rob Stewart’s followup to his 2006 feature shines a light on human cruelty – and gains power from the fate of its maker

    In the 2006 eco-doc Sharkwater, Canadian activist film-maker Rob Stewart gave us a heartfelt plea to save the planet’s sharks. He was on a mission to reduce overfishing and rehabilitate the creatures’ reputation as stone-cold killers – if only we could love sharks as much as we love cuddly pandas we’d do more to protect them. Back then, you couldn’t help feeling that Stewart wanted us to love him too, with all the shots of himself in tiny Speedos. Watching the sequel, I experienced a sharp stab of self-reproach. Stewart died in a diving accident while shooting this film – he was 37. Sharkwater: Extinction has been scrappily put together from footage he’d already shot.

    And there are some striking images here. Since the first film, many countries have banned “finning” ­– the practice of hacking off the fins then tossing the shark’s body back into the sea. But it still happens. In Costa Rica, Stewart uses a drone to film a warehouse packed with them. Shark fin soup is a delicacy in China, which drives the illegal market. And it’s not just finning that’s the problem. In California, he captures upsetting footage of a graceful thresher shark tangled up in a mile-long net intended for swordfish.

    Continue reading...

  • World Water Day study highlights lethal nature of unsafe sanitation and hygiene for children, especially under-fives

    Children under five who live in conflict zones are 20 times more likely to die from diarrhoeal diseases linked to unsafe water than from direct violence as a result of war, Unicef has found.

    Analysing mortality data from 16 countries beset by long-term conflict – including Afghanistan, Iraq, Syria and Yemen – the UN children’s agency also found that unsafe water, sanitation and hygiene kills nearly three times more children under 15 than war.

    Continue reading...

  • Science agency says scourge of wandering trad could be slowed by fungus, which they have called its ‘natural pathogen’

    Australia’s national science agency will release a Brazilian leaf smut fungus to target and kill an invasive weed that covers large parts of the continent’s east coast.

    Researchers from the CSIRO say the scourge of wandering trad could be slowed by the introduction of the Kordyana brasiliensis fungus, which they have called its “natural pathogen”.

    Continue reading...

  • While the ultimate goal is to stop plastics from entering the water in the first place, cleanup projects play an important role

    Somewhere in Hilo, on Hawaii’s Big Island, a team of scientists and engineers are tending to The Ocean Cleanup’s 600-metre-long rubbish-herding device, after its maiden voyage to the Great Pacific garbage patch was cut short in December 2018, because it fractured into two pieces.

    The project has had its fair share of problems since it was unveiled in May 2017 and has been criticised by marine scientists and environmental groups for its potential negative environmental impact. However, some still herald The Ocean Cleanup for having a positive effect on plastic pollution.

    Continue reading...

  • The latest study warning us to eat less meat has brought angry sceptics out in droves. But who should we believe?

    Sometimes, particularly when looking at the weekend newspapers, it can seem that our obsession with food and health has reached a pitch of pure hysteria. “Eat!” screams one headline. “Diet!” shouts another. Cut out carbohydrates, suggests one report. Carbs are good for you, says a different one. Lower your fat intake. No, fat’s healthy, sugar’s the problem. Coffee raises the risk of heart disease. But it lowers the risk of diabetes. And so on, until you just want to ditch the papers and watch The Great British Bake Off or MasterChef.

    Food, how to cook it, what it does to you and what growing or rearing it does to the planet are issues that crowd the media. And yet, as the clamour grows, clarity recedes. An estimated 820 million people went hungry last year, according to the UN Food and Agriculture Organisation. A third of all people were vitamin-deficient. Two billion were classified as overweight and 600 million as obese. It’s also estimated that 1bn tonnes of food are wasted every year – a third of the total produced. A plethora of academic reports concerning food consumption and production have been published in recent years. The latest and arguably the most far-reaching is Food in the Anthropocene:the Eat-Lancet Commission on healthy diets from sustainable food systems, which was conducted over three years by 37 senior scientists from around the world and published earlier this year.

    Continue reading...

  • Scientists say a drastic cut in meat consumption is needed, but this requires political will

    It has been known for a while that the amount of animal products being eaten is bad for both the welfare of animals and the environment. People cannot consume 12.9bn eggs in the UK each year without breaking a few.

    But the extent of the damage, and the amount by which people need to cut back, is now becoming clearer. On Wednesday, the Lancet medical journal published a study that calls for dramatic changes to food production and the human diet, in order to avoid “catastrophic damage to the planet”.

    Continue reading...

  • The continent’s largest land mammal plays crucial role in spiritual lives of the tribes

    On 5,000 hectares of unploughed prairie in north-eastern Montana, hundreds of wild bison roam once again. But this herd is not in a national park or a protected sanctuary – they are on tribal lands. Belonging to the Assiniboine and Sioux tribes of Fort Peck Reservation, the 340 bison is the largest conservation herd in the ongoing bison restoration efforts by North America’s Indigenous people.

    The bison – or as Native Americans call them, buffalo – are not just “sustenance,” according to Leroy Little Bear, a professor at the University of Lethbridge and a leader in the bison restoration efforts with the Blood Tribe. The continent’s largest land mammal plays a major role in the spiritual and cultural lives of numerous Native American tribes, an “integrated relationship,” he said.

    Continue reading...

Eco Health News feeds

Eco Nature News feeds