Vacations are supposed to leave you feeling relaxed, happy, and healthy — but if you travel by air, you might feel worse by the time you get home than you did when you left.

Fear of flying? For good reason.

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Flying should not generally be the transportation option of choice for the environmentally minded, given its intensive use of resources. (Intercity buses consume less than a fifth the energy jets do to cover the same amount of distance.) And not only is it lousy for the Earth, it’s not great for your own health, either.

Returning to the U.S. recently on an Air Jamaica flight, I felt so ill that I almost lost consciousness. I was overcome with nausea and dizziness, and when I tried to talk, my husband reported that I didn’t make sense. He thought I was having some sort of seizure. In reality, I was having an allergic reaction to an agent (not the federally employed kind) in the cabin air.

Jamaica is one of 12 countries that require routine “disinsection” — the spraying of pesticides — on all inbound flights. Grenada, India, Kiribati, Madagascar, Trinidad and Tobago, and Uruguay require spraying while passengers are on board; flights to Jamaica, Australia, Barbados, Fiji, New Zealand, and Panama may be disinsected when the plane is either empty or occupied. In addition to national air carriers (such as Air Jamaica), all U.S. airlines comply with these nations’ requirements.

Disinsection is meant to kill any insects that might pose a threat to plant, animal, or human health. (There are PR considerations as well: As a spokesperson for U.S. Airways put it, “No one likes seeing a spider on a flight.”) And no doubt about it, invasive species are a huge environmental problem: At least 4,500 nonnative animals and plants have established populations in the U.S., and approximately 15 percent of these are doing serious damage to native species. This seems to pitch environmentalists onto the horns of a dilemma: Which is worse, pesticide exposures or invasive insects?

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Danger, Will Robinson!

But actually, the dilemma is a false one. First, the efficacy of spraying is questionable, since insects may travel inside luggage, where the pesticide won’t harm them. And the best practices for spraying are murky: “We have evidence of huge differences in spraying methods between airlines,” said Judith Murawski, an industrial hygienist with the Association of Flight Attendants. “Some airlines have admitted to overspraying. Some spray down at ankle level with the doors open.” Moreover, there are mechanical solutions that may be preferable to pesticides; Murawski notes that the U.S. Department of Transportation is testing the feasibility of blowing compressed air across passengers as they enter jets as a means of driving away pests.

Air Jamaica sprays its planes once a month with Demon WP, a synthetic pyrethroid insecticide. According to the airline’s sprayer, Target Industries, the insecticide remains effective for up to several weeks. The U.S. EPA does not regulate the use of synthetic pyrethroids. According to the Centers for Disease Control, pyrethroids interfere with human nerve and brain function. Skin contact may cause numbness, itching, burning, or stinging. Very high levels of exposure can cause reactions ranging from “dizziness, headache, and nausea” to “muscle twitching, reduced energy, and changes in awareness” to “convulsions and loss of consciousness,” the CDC reports.

Seeking to prevent routine spraying, United flight attendants and passengers filed lawsuits in August 2001 that have stalled since the airline declared bankruptcy in December 2002.

Steps to Help You Breathe Easy

  • If you’re concerned about exposure to onboard pesticides, ask before buying your ticket whether an insecticide will be sprayed on the flight. You may want to change your airline, or — if the flight is to a country that requires spraying — your destination.


  • People who have allergies or asthma or are pregnant and are booked on a flight requiring onboard spraying can request an exemption, the Fair Air Coalition says. “The exemption only works if the spraying is done after landing,” says Diana Fairechild, founder of the Fair Air Coalition, “though it’s possible that if spraying does occur normally during flight you can ask them to spray after. The exemption will allow you to get off before the spraying on the ground, but no other passengers can deplane.”


  • Before onboard spraying, cover yourself with a blanket.


  • If the plane on which you will be flying is sprayed when unoccupied, ask for assurances that the cabin will be aired out before boarding and ventilated with fresh air during the flight.

More resources: The Department of Transportation’s website has information on disinsection. The Agency for Toxic Substances and Disease Registry has info on pyrethroids. The Fair Air Coalition and the Association of Flight Attendants are two organizations that seek to prevent routine spraying of pesticides on airplanes.


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