Common chemicals increase risk of heart attack and stroke by up to 45 percent
Two simple steps you can take to keep yourself—and the planet—safe

For many Americans, fresh produce is coming back into season this month (see my article about keeping them fresh, on page 7). So consider this my seasonal warning about just how many of the fruits and vegetables we buy are covered in toxic pesticides and insecticides.

In fact, the vast majority of fruit and vegetable crops are doused in agricultural chemicals that are harmful not only to our health, but also to the health of our environment.

I’ve witnessed this effect personally over the last four decades. The southeast Florida coast (where I worked as a medical examiner in the mid-1980s) experienced serious die-off of its undersea coral reef (the third largest in the world) due, in part, to agricultural chemicals being washed from farmland into the water.

And on the Gulf Coast (where I now reside in my Florida home), the water lacks oxygen because of the effects of agricultural chemicals. This has created a “dead zone”—the size of Massachusetts—that kills fish and other marine life.1 (For more about the danger of dead zones, see the sidebar on page 6).

The direct link between pesticides, insecticides, and chronic diseases

Of course, that’s not the only living thing agricultural chemicals can kill. I’ve written before about studies showing that these toxic insecticides, pesticides, and herbicides (like Roundup®) have a direct effect on humans’ risk of dying from chronic diseases.

Many of these studies have—appropriately—focused on how these chemicals can cause cancer. But researchers are also branching out to look at how agricultural toxins affect other chronic diseases, too.

Two new studies show that pesticide and insecticide exposure substantially increases our risk of heart disease—the world’s No. 1 killer.

One of the studies even found that a supposedly less-toxic agricultural insecticide, which is commonly sprayed into the air around us to repel mosquitos and other pests, can triple our likelihood of dying from heart disease.

The good news is that there are two simple solutions to help preserve both our health and the health of our planet. I’ll reveal them in just a moment…but first, let’s take a closer look at this deadly new evidence on the ill-health effects of chemical pesticides and insecticides.

Pesticides linked to a 45 percent increased risk of heart attacks and strokes

The first study is the most recent to come out of the Kuakini Honolulu Health Program, which has followed more than 8,000 first- and second-generation Japanese-Americans since 1965.2 (I was offered a position with the Kuakini study in 1979, to continue my research on Asian-American populations, but decided it was best to stay on the mainland at that point in my career.)

Researchers looked at men who were exposed to pesticides through their work. And they found that these men had a shocking 45 percent higher risk of having a heart attack or stroke compared with men who didn’t work with pesticides.

Similar results were also found in the Republic of China (Taiwan) among middle-aged men who had high levels of pesticide exposure.

By analyzing different time periods, the researchers found that the maximum heart attack and stroke risk was during the first 10 years following pesticide exposure. After the full 34 years of follow-up, the link between pesticides and cardiovascular disease was no longer significant.

But at that point, the men in the study were between 78 and 102 years old, and the researchers noted that other risk factors for heart disease had appeared—potentially masking the pesticide risk factor.

The canary in the coal mine when it comes to pesticide exposures

If you think this study doesn’t apply to you because you don’t work with pesticides, consider this: Exposures on the job reveal health problems linked to chemicals first, because the workers have higher and more continual exposure compared with the general population.

In essence, these people are like the “canary in the coal mine,” indicating there’s a risk for the general population.

For example, people who worked on golf courses for years have shown increased risk of cancer. The use of pesticides on golf courses is intense and essentially year-round, so health risks show up first among the people who work there. Not to mention, if a worker is exposed to one cancer-causing chemical on the job, he or she is invariably exposed to a dozen or more.

But, as I learned to my great dismay as a forensic toxicology expert witness on a case in 2014, judges can demand data on each individual type of pesticide exposure—and reject what they call a “toxic soup” argument (the combination of all of the different chemical exposures that occur together in reality).

Of course, such data simply does not exist in humans, but that doesn’t stop lawyers from asking experts to try to “prove” the impossible. And thus, numerous chemicals continue to be widely used without accountable consequence.

This dilemma is depicted in the book and 1998 film, “A Civil Action.” The focus was on the link between childhood cancer and the pollution of the historic Aberjona River, done illegally by W.R. Grace and Beatrice Foods, near my old hometown in Massachusetts during the 1960s and 1970s.

In the film, the law firm of John Travolta (as real-life attorney and author Jan Schlichtmann) attempted to try this case. It bankrupted the law firm and led to increased anxiety (which I had also seen coming for me as a forensic toxicology expert witness in 2014, until my doctor recommended I retire from this kind of practice).

There’s no “safe” insecticide

The second study linking agricultural chemical exposure to heart attacks is even more shocking than the first. That’s because it has to do with a family of insecticides that farmers and chemists have deemed “safer” than other chemical bug killers. And people use them quite commonly.

These insecticides are known as pyrethroids, and they’re sprayed on a variety of crops to kill ants, roaches, mosquitoes, and ticks. According to Consumer Reports, pyrethroids account for 30 percent of the insecticides used worldwide. And they’re now the most common chemical used to kill mosquitos in the U.S.3

Pyrethroids are typically diffused into the environment, rather than used in insect repellants you apply topically to your skin. But the Centers for Disease Control and Prevention does recommend spraying the chemicals onto clothing to help repel ticks. And they’re a common ingredient in lice shampoos and pet flea medications, too.

Pyrethroids are supposedly less harmful to birds and mammals (including humans) than other chemical concoctions because they’re related to pyrethrins, which are natural insecticides that come from chrysanthemums.

But pyrethroids are made from synthetic chemicals, so whatever “natural” link they supposedly have no longer exists. In essence, this artificial alteration turns a harmless herbal remedy into a toxin.

So it’s really no surprise that pyrethroids have nasty side effects for humans—including headache, vomiting, dizziness, muscle twitching, and even loss of consciousness.4 Which leads me to this new study, which found an even more toxic side effect…

The insecticide that makes you three times more likely to die from heart disease

Researchers followed 2,116 men and women (average age of 43) who participated in the U.S. National Health and Nutrition Examination Survey.5  The participants provided urine samples over a three-year period, and the researchers measured concentrations of a number of chemicals that indicate exposure to pyrethroids.

The researchers discovered that the participants with higher exposures of pyrethroids were three times more likely to die from heart disease compared to those with lower exposures. And pyrethroid exposure was more likely to lead to death from any cause. The researchers expressed surprise at these findings—even though another study in 2017 also found a link between pyrethroids and heart disease.6

My two-step plan to protect yourself from pesticides and insecticides

The sad fact is that these toxic agricultural chemicals are all around us. But there are two easy and effective steps you can take to reduce—or even eliminate—your exposure to deadly pesticides and insecticides.

1.) Eat organic fruits and vegetables. By U.S. law, produce that’s labeled organic can’t be grown with chemical pesticides, herbicides, insecticides, or fertilizers.

But if you can’t always afford to buy organic produce, focus on the fruits and vegetables that are most likely to be contaminated with pesticides. I always recommend checking out the nonprofit Environmental Working Group’s (EWG) website,, for guidance. They release a “Dirty Dozen” list each year, and the most recent list includes (in order of the most contamination):

1) Strawberries   7) Peaches

2) Spinach          8) Cherries

3) Kale                9) Pears

4) Nectarines      10) Tomatoes

5) Apples            11) Celery

6) Grapes            12) Potatoes

2.) Protect yourself from pests naturally. Wear long sleeves, pants, and socks at dawn and dusk (which is prime mosquito time) and in places where you may be exposed to ticks.

In addition, clean up any standing water around your home, which attracts mosquitos. And repel other insects by keeping compost piles far away from the house.

There are also a variety of common, hardy plants you can grow around your house, patio, and other outdoor areas that act as natural insect repellants, including basil, catmint, chrysanthemums, geraniums, lantana, lavender, lemongrass, marigolds, mint, and rosemary.

You can use essential plant oils as insect repellents as well. Citronella and eucalyptus oils are particularly effective. Just combine 10 to 25 drops of either plant oil with two tablespoons of olive oil—to be applied directly to the skin or used as a spray.

How pesticides and insecticides pollute our water

From my Florida home, I see daily evidence of one of the most dramatic environmental impacts of agricultural chemicals.

Florida has the longest coastline in the lower 48 states, adding up to nearly 9,000 miles (Alaska is first with over 33,000 miles).7 Florida is also an agricultural breadbasket. So every time it rains (and it rains a lot here!), toxic pesticides and insecticides get washed into the Gulf of Mexico and the Atlantic Ocean.

Plus, the mighty Mississippi River also drains into the Gulf, carrying runoff from farms in the agricultural Midwest—where use of chemical pesticides and insecticides has become intense.

And if all that weren’t enough, the manmade alteration of the natural waterflow of the Everglades (in order to create more agricultural land and coastal development) disrupts the natural, cleansing watershed into the Gulf.

All of this creates a critical environmental issue: dead zones in the Gulf of Mexico, where no plant or animal can thrive.

There was a slow expansion of dead zones during the second half of the 20th century, and then they skyrocketed in the early 21st century. That’s when ridiculous federal government mandates started requiring the contamination of gasoline with ethanol, for absolutely no good reason. This ethanol is made from corn—which is now almost all genetically modified (GM) and requires the most intensive use of agricultural chemicals of any major crop. (It’s grown in the Midwest and drained into the Mississippi.)

But these dead zones shrunk in 2012, when a major drought in the Midwest kept toxic chemicals from washing down the Mississippi into the Gulf of Mexico.

This is good news, though…that nature can begin to come back so quickly. It also demonstrates the cause and effect connection between agricultural chemicals and the death of our oceans. And now, ever since, restrictions on chemical use on Florida farmlands, as well as limits on local development and efforts at environmental restoration, are yielding positive results.

A real solution to ending dead zones in the Gulf of Mexico and other bodies of water throughout the world is to stop buying, selling, and using mass-produced GM crops that are mono-cultured on mega-farms, and to consume locally grown, organic foods. That’s just one reason why I’ll continue visiting my local farmer’s market this summer—and all year long.



2“Association Between Occupational Exposure to Pesticides and Cardiovascular Disease Incidence: The Kuakini Honolulu Heart Program.” Journal of the American Heart Association, 2019; 8 (19).



5“Association Between Exposure to Pyrethroid Insecticides and Risk of All-Cause and Cause-Specific Mortality in the General US Adult Population.” JAMA Intern Med. 2019 Dec 30.

6“Nonoccupational Exposure to Pyrethroids and Risk of Coronary Heart Disease in the Chinese Population.” Environ Sci Technol. 2017 Jan 3;51(1):664-670.