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When We Fumigate Flies and Mosquitoes, Are We Poisoning Ourselves?

In supporting the fumigation of insects in Central America, is the US poisoning civilians?

(Image: Mosquito fumigation via Shutterstock)

We arrived at the Las Manos border between Honduras and Nicaragua at nightfall. Our 24-person permaculture group had already been sitting in a van for nearly 24 hours, cruising the Pan-American Highway – the world’s longest “motorable road” – from Guatemala.

As we slowed to a stop behind a long row of cars, we spotted a man with a handkerchief over his face and scant other protective gear. He was curved forward, holding a metal hose and spraying the lower parts of each passing vehicle.

“Poisonous Gases Fumigation Area” was written in Spanish on a looming billboard.

My eyes stung and I began to cough. Whatever had been sprayed was drifting in the air, invisible but poisonous.

Questions flooded into my mind: Why wasn’t the man wearing proper safety equipment like an oxygen mask, overalls, boots and gloves? What were they spraying on the vehicles, specifically the wheels? Did insects really hitch rides on tires? If so, which ones?

As someone who suffers from an autoimmune condition and is extremely sensitive to chemicals, this site freaked me out; it all seemed dangerous and foolish.

“We’re fucked to the max,” one of my fellow travelers, a former deputy district attorney from Colorado, announced.

We were not warned. We were not advised. And we were not asked whether we wanted to vacate the vehicle during this sick rendition of a car wash.

Instead, we frantically rolled up our windows, asked our driver to cut the air and hoped for the best. Had the fumigators searched inside, they would have found some fruit and a live iguana that we’d bought on the side of the road for 10 bucks to keep it from ending up on someone’s dinner plate (iguana is a popular meat in Central America).

After our van was fumigated, we were immediately asked to wait in a long line to show our passports to gain entry. My eyes stung and I began to cough. Clearly whatever had been sprayed was drifting in the air, invisible but poisonous.

Welcome to Nicaragua.

Getting to the Bottom of the Fumigation Mystery

I conducted preliminary research into this unexpected chemical attack in the evenings after permaculture class. We were now on the last leg of our three-week journey, which was unfolding at Surfing Turtle Lodge, a beachfront hostel located on a beautiful stretch of empty Nicaraguan beaches in Isla Los Brasiles on the Pacific Coast.

The internet connection was molasses as I perched in my bed du jour. I was sharing a small, one-roomed, wooden bungalow with the ocean practically crashing at my feet. Despite the slow connectivity, I persisted; I wanted to look into a lead my permaculture teachers Ronaldo Lec Ajcot, a Maya Kaqchikel man from Guatemala, and Shad Qudsi of Atitlan Organics had provided. They suspected that the chemical fumigation was part of a program called Moscamed.

The ultimate fear driving this eradication program is that the medfly will make its way to the US.

Moscamed (a Spanish abbreviation for “Mediterranean fruit fly”) is an enormous joint eradication program financed by the United States that involves Guatemala and Mexico. The pest in question is the Mediterranean fruit fly, also known as the medfly, “a destructive little fly that breeds 10 generations a year” and has “slipped with ease across vast oceans.” The female medfly attacks ripening fruit and vegetables (about 200 kinds of produce), piercing the soft skin and laying up to 75 eggs in the puncture. The eggs then hatch into larvae (maggots), which feed deep inside the fruit pulp.

The ultimate fear driving this eradication program is that the medfly will make its way to the United States. The long-term mission is to wipe out the fly throughout Central America.

“Maintaining a Medfly barrier in Central America protects our multibillion dollar fruit and vegetable industry, and allows us to maintain and expand market share in domestic and international markets,” according to a blog post on the US Department of Agriculture’s (USDA) website.

I eventually learned that the fumigation that I experienced at the border was not, in fact, conducted by Moscamed, as my permaculture teachers had assumed, but was instead conducted by Organismo Internacional Regional de Sanidad Agropecuaria (OIRSA), an intergovernmental organization founded in 1953 that provides technical assistance to the ministries and departments of agriculture and livestock of nine member states: Belize, the Dominican Republic, Guatemala, Honduras, Nicaragua, Panama, El Salvador, Mexico and Costa Rica.

It was the Animal and Plant Health Inspection Service (APHIS), a USDA agency, that was finally able to clarify for me that OIRSA was the agency behind the spraying.

“It is definitely OIRSA who sprays the cars at the borders,” John Hurley of APHIS told me via email. “They also work at all the airports and seaports. They even give you a receipt…. I’ve been sprayed going into Belize and Mexico from Guatemala by OIRSA.”

I spent the next four months trying to contact Raúl Antonio Rodas Suazo, the director in charge of quarantines at OIRSA. He was always busy or out of the office. Finally, he responded via email, asking me for more details. But despite my prompt response, I never heard back. Finally I wrote, stating that I would assume his nonresponse meant that whatever they were spraying was dangerous to humans. He never wrote back.

Dr. Pablo Liedo, Ph.D., a researcher at El Colegio de la Frontera Sur (ECOSUR), a public scientific research center that aims to contribute to sustainable development of the southern border of Mexico, Central America and the Caribbean, told me that OIRSA’s failure to respond to my questions was typical.

“The current situation in OIRSA is chaotic; do not expect any response from them,” he said.

Poisons to My Left, Poisons to My Right

The final leg of our trip was to a festival called Envision in Costa Rica, where I was destined to give a talk on honeybees. I’d traveled back to León, Nicaragua, a day earlier than my group. Upon arriving, a couple informed me that their hostel had been fumigated. They were in their room getting dressed when suddenly someone inserted a hose underneath the door. Before they knew it, they’d been gassed.

I asked the boutique Hotel Azul where I was staying if they’d also been fumigated; the pregnant concierge informed me that they turned the request down. Later that day I discovered that the owner of an organic juice bar and saline pool had also objected to the fumigations.

It turned out that President Daniel Ortega had sanctioned regular fumigations throughout the capital of Managua, as well as Chinandega and León, in order to tackle chikungunya (pronounced chick-un-GOON-ya), a virus that is transmitted via mosquitoes. A health alert had been declared throughout the nation based on the recent death of a child due to chikungunya, and two deaths from dengue. As part of the measures, the government now fumigates every seven days. Chikungunya has rampaged through the Caribbean and Latin America, already infecting nearly 1 million people.

While I escaped being fumigated in the streets and in my hotel room, when our group reached the Nicaraguan and Costa Rican border, we encountered yet another fumigation area. And once again we were exposed to poisons.

US Funding for the Indiscriminate Use of Fumigation in Central America

My own experience of fumigations in Central America intensified my concern and curiosity about toxic practices and the effects of widespread use. As I did more research, I found that US funding has perpetuated the indiscriminate use of chemicals in Mexico and Central America, particularly in the context of the Moscamed campaign to eradicate the Mediterranean fruit fly. That is why permaculture teachers had initially (and erroneously) jumped to the conclusion that the spraying that I experienced at the border between Honduras and Nicaragua was part of the Moscamed protocols.

This year, the United States, Mexico and Guatemala entered a new trilateral cooperative agreement related to control of the Mediterranean fruit fly and other fruit flies of economic significance. These three governments now operate the medfly program activities under the Moscamed Commission.

The United States, Mexico and Guatemala first initiated the cooperative Moscamed program in 1977, after the Mediterranean fruit fly infested Mexico’s southern Chiapas state. Moscamed’s introduction coincided with the arrival of new agricultural pests, according to Nicholas Copeland, a social anthropologist and assistant professor at Virginia Tech.

In his 2014 article, “Mayan Imaginaries of Democracy,” he cites Mayan villagers who witnessed planes flying over their villages and fields, spraying pesticides and herbicides. Children exposed to the chemicals would cough and vomit.

Moscamed sprayed malathion almost indiscriminately for 20 years, in many cases directly on people’s homes.

From 1977 through 1999, the Moscamed program’s insecticide of choice was malathion, which is considered to be one of the most dangerous poisons to humans and highly toxic to bees, fish and shellfish. This potent broad-spectrum pesticide was sprayed over large areas containing villages, bodies of water and endangered animal species, all in the name of reducing world hunger.

Representatives from the USDA’s Animal and Plant Health Inspection Service told me that they’ve “demonstrated a long term and unparalleled commitment to honeybee health.” They report that the Moscamed Commission “has a good track record of working with honeybee producers throughout Central America and serves as a model for other countries to emulate.”

But according to other reports, Moscamed sprayed malathion almost indiscriminately for 20 years, in many cases directly on people’s homes, which in rural villages are often located within sprayed fields, and without informing the inhabitants of the safety risks or necessary precautions, writes Copeland, who investigated mistrust of the program among indigenous villagers in rural Huehuetenango, a Guatemalan department located in the northwest, along Mexico’s southeastern border.

From 1985 to the present, the USDA states it has conducted environmental monitoring for pesticide residues by taking baseline samples of soil, foliage, fruit and water and sending them to the USDA National Residue Monitoring Laboratory in Gulfport, Mississippi. The USDA reports that results of these tests show that only trace amounts of pesticide are detectable, but concerns persist about the ongoing effects of chemical sprayings on the people exposed.

In 1988, the Consortium for International Crop Protection conducted an environmental impact analysis and discovered that fumigation stations used various formulations of toxic chemicals, such as dichlorvos and propoxur, which should have been phased out. They also found workers at one station playing cards in the methyl bromide fumigation chamber. Methyl bromide is highly toxic to humans. Other workers were found sleeping in the chambers at night. The consortium also learned of one incident where the fumigation chamber was only equipped with one respirator and since it takes two workers to handle the fruit, the other worker simply wraps a handkerchief around his nose and mouth before entering – a paltry form of protection reminiscent of what I witnessed during the fumigation on the border between Honduras and Nicaragua.

In 2000, Moscamed switched from malathion to spinosad, which the USDA claims is less toxic to non-target insects. “Spinosad bait spray also offers other advantages: it is approved for organic production by the USDA National Organic Program and other international certifiers, and it repels honeybees and other pollinators. The bait component contains ammonium acetate, that attracts female Medflies and repels honeybees,” states the Animal and Plant Health Inspection Service. But according to Environmental Protection Agency (EPA) documents, spinosad, too, is highly toxic to beneficial honeybees.

Low-Intensity Chemical Warfare?

According to the Animal and Plant Health Inspection Service, Moscamed is deemed a successful program. But how does one measure success in a war that has been waged against the same insect for almost 40 consecutive years? When I reached out to the inspection service, its public affairs specialist was quick to tell me that the service uses “biological and organic means of pest control” and currently supports a beekeeping training and development center in Guatemala.

Her claims about the program’s biological rather than chemical approaches to pest control are a reference to the program’s “sterile insect technique,” which involves exposing 500 million fruit flies to gamma rays each week and then reintroducing them as sterile mates in an attempt to breed sterility into the population.

Mayan activists are less sanguine about the eradication program’s effects on their communities. A Zapatista communiqué described Moscamed as “low-intensity chemical warfare” against communities in rebellion. Of all the governmental programs in Guatemala, Moscamed is arguably the least popular among rural Mayans. In his 2014 article, “Mayan Imaginaries of Democracy,” Copeland describes how most Mayas in the northwest region believe that the program is part of an agribusiness and government scheme to undermine rural agriculture, particularly maize, by spreading pests that will require them to buy expensive pesticides – and get them addicted to chemical inputs. In addition to wondering what this conspiracy reveals about how indigenous people perceive and experience politics, he has called for an independent investigation of the environmental effects of the Moscamed program on indigenous communities.

Some contend that medfly populations could be better managed through diligent collection and disposal of affected fruits, and an effort to keep populations of beneficial insects healthy. Spraying coffee, maize, beans, pineapple, bananas, and other fruits and vegetables have created smaller than usual fruits and vegetables that mature and rot earlier than usual. Yields have also been dramatically reduced. Meanwhile they have witnessed explosions of worms and new outbreaks of pests such as the coffee borer.

“The people would say, ‘Before, this used to be a clean area,'” Ana Gonzalez, a biologist who worked in Lachua, an agricultural region in northern Guatemala, told RedOrbit. “But that was until the planes came and dropped bags full of worms all over our crops.”‘

In Lake Atitlán, a region nestled in the highlands of Guatemala, modern techniques, including chemical fertilizers, insecticides and monocultures, have led to soil degradation and subsequent malnutrition. Meanwhile agricultural runoff has contaminated this once pristine lake.

The Moscamed program protects a multibillion-dollar US fruit and vegetable industry and allows for continued expansion of market share in domestic and international markets, said Abbey Powell, USDA APHIS spokesperson. The amount of losses estimated to be incurred by the United States with a widespread medfly infestation is more than $2 billion a year. Annual losses in Mexico should the fly become established are estimated to be $1.6 billion. Moscamed’s annual budget is approximately $40 million.

“This contribution helps to achieve the millennium goal of reducing hunger in the world, by preventing potential losses which may occur in the absence of the Moscamed program, in host fruit and vegetable crops,” Powell added.

It seems that whenever it comes to genetically modified crops, the spraying of toxic chemicals or the dropping of sterilized flies from the sky, proponents of these practices are eager to justify them in the name of “reducing hunger in the world.”

And when it comes to fumigation programs or aerial application of insecticides, they are ostensibly ineffective. The repeated use of a pesticide brings about resistance in target populations, according to Drew Toher, Beyond Pesticides’ public education associate.

Take for instance West Nile virus “prevention”: While many billions of spray droplets are produced per kilogram of insecticide for both ground and aerial spraying, “less than 0.0001% of the insecticide applied is reaching the target mosquitoes. Thus by both ground and aerial application 99.999% of the insecticide spreads into the environment,” where it can “cause public health and other environmental problems,” writes entomologist David Pimentel of Cornell University.

The Neurotoxic Effects of Pyrethroids

Upon my return to the United States, my autoimmune condition flared up, and when I visited the doctor, my test results indicated that my thyroid levels had plummeted below normal. I often tell people that those who suffer from autoimmune conditions are environmental indicators just like our honeybees.

Dr. Pablo Liedo, the researcher I spoke with from ECOSUR, continued to try to contact OIRSA on my behalf to obtain more information about the chemicals to which I was exposed, with no success.

“What I know they apply to cars at the border are pyrethroids, the same products they sell for home and garden use,” he told me. “These insecticides are the most safe for humans, but I am very skeptical about the usefulness of these applications to prevent the introduction of pests.”

Pyrethroids have been known to cause immediate side effects such as coughing, wheezing and difficulty breathing. And many pyrethroids, according to Beyond Pesticides, have also been linked to the disruption of the endocrine system by mimicking the female hormone, estrogen. There is also evidence that pyrethroids, which are classified by the EPA as class C (possible human) carcinogens, can harm the thyroid gland. Meanwhile neurotoxic effects include tremors, incoordination, elevated body temperature, increased aggressive behavior and disruption of learning. These are by the way the same “safe” poisons they use on aircrafts.

And like all toxins, they are indiscriminate; they affect all organisms that come into contact with them in the air, on plants, on the ground, in the soil and in the water. And, since particulates are easily airborne, they travel, often great distances, from the actual point of application.

So if you’re traveling across Central America and crossing borders via a motor vehicle, plan on getting sprayed at the border. You may even be asked to pay a fee, but in the long term the experience of fumigation may cost you a lot more than just a few quetzals or colónes.