EDITOR’S SUMMARY: The more knowledge you have, the more choices you’ll become aware of. And while you can “pick your battles,” you can also “meet your opportunities.” So what is there to do about the minuscule amounts of hexane lurking in your food that you cannot see? The FDA deems it a food additive “permitted for human consumption.” Yet there are multiple studies denoting its health risks. It’s a chemical made from crude oil, after all. Should it really have a place in the production of foods sold at your local grocer, fed to your children, and served at your favorite restaurant?
By Carter Trent
Today’s industrialized society delivers mass food production, and it comes at a cost. Not all toxins in products are listed on ingredient labels, as they’re considered “processing aids,” (a.k.a. “additives”) in food manufacturing. These hidden substances are not technically “ingredients,” but they’re not insignificant. One of the most widely-used processing aids in the food supply is hexane, which is made from petroleum. Yes, it’s the same stuff that goes into your car’s gas tank, and it’s highly probable you have ingested it.
The food industry uses hexane primarily for the extraction of oils from plants, seeds, and vegetables such as soybeans (also considered a legume). It is derived from a process used by oil refineries when making gasoline. As a refinery breaks down petroleum to manufacture automotive fuel, the procedure generates byproducts, including hexane. It is then used as a synthetic solvent throughout a wide range of industries, from car repair, to glue for shoemaking, and rubber and textile manufacturing. In the food industry, many cooking oils are prepared using hexane, including peanut, soy, canola, corn, grapeseed, cottonseed, rice bran, safflower, and sunflower. You may be surprised to learn that olive oil can contain hexane too—unless your bottle says “extra virgin,” since the term “virgin” denotes oil that is squeezed from the olive, rather than extracted by a solvent. Hexane is also part of the process used in making beer, to separate out the hops. Additionally, the solvent is applied in the manufacturing of nutraceuticals, including essential oil extracts and nutritional supplements. From ScienceDirect:
“Nutraceutical is a term derived from the words “nutrition” and “pharmaceutical,” and could be defined as “any substance that is a food or a part of a food and provides medical or health benefits, including the prevention and treatment of diseases.”
Soybean production: Hexane is used to separate out soybean oil, or soy protein, for use in a variety of products, such as chips and “nutrition” bars. The soybeans are first cleaned and dehulled, then cooked, and turned into flakes to make it easier for the hexane to permeate the soybeans’ cells; this helps to extract more oil. The flaked soybeans are then soaked in a bath of hexane, which dissolves the oil from the solid plant material. This creates two byproducts: a mixture of hexane and oil called miscella, and a meal from the plant material. Both undergo heating to release the hexane, which is captured to be recycled for future use. At this point, with the hexane evaporated, you’re left with just the oil and meal. Residual amounts of hexane remain in each.
Hexane extraction is carried out on a large scale in palm oil production, the most widely-used edible oil on the planet. It’s implemented due to its ability to draw out larger quantities of oil from the plant material than any other technique, including mechanical pressing. In addition, hexane is cheap, and can be recycled for reuse. It must be noted that pushing the palm oil industry to the point of deforestation has significant consequences for land, humans, and animals. From Rainforest Action Network, “Frequently Asked Questions About Palm Oil”:
“Palm oil has become one of the world’s leading causes of rainforest destruction. Unchecked expansion has pushed palm oil plantations into the heart of some of the world’s most culturally and biologically diverse ecosystems and palm oil is among the biggest threats driving iconic wildlife species like the Critically Endangered Sumatran orangutan and the Endangered Borneo orangutan to the brink of extinction in Indonesia and Borneo Malaysia.
This large-scale destruction of rainforests and carbon-rich peatland landscapes is releasing globally significant quantities of carbon pollution into the atmosphere, making palm oil a major global driver of human induced climate change.
The production of palm oil is also responsible for widespread human rights violations as palm oil companies often forcefully remove Indigenous Peoples and rural communities from their lands. Child labor and modern day slavery are known to occur on palm oil plantations in both Indonesia and Malaysia.”
Despite its toxic nature, and the availability of natural alternatives such as methyloxolane, hexane use is expected to grow well into 2027, as demand for edible oils, such as palm oil, continues to increase.
Hexane’s Effect on Your Health
Because the amount of hexane residue from food processing is low, and the hexane that hits your body exits through your urine, it’s assumed to be harmless. And yet, no study has determined a safe daily intake level, let alone the impact of cumulative hexane exposure over years of consumption. What is known about the dangers of hexane is the fact that it is a neurotoxin. As such, it can cause damage to your central nervous and reproductive systems. That’s why California includes hexane in its Proposition 65 list of chemicals causing cancer or reproductive harm. It’s been documented that exposure to hexane starting at 500 milligrams per liter caused nerve damage to workers in factories during the 1960s and ‘70s. Hexane causes other harmful health outcomes too, such as damage to your DNA when it metabolizes into the toxic substance 2,5-hexanedione in your body. From “Toxicological Profile for n-Hexane”:
“The neurotoxicity of n-hexane was first observed in the shoe industries of Japan and Italy in the 1960s and early 1970s. A number of epidemiological studies were initiated in response to outbreaks of apparent peripheral neuropathy in shoe workers. While the clinical course of the disease was well described, elucidation of a dose-duration response relationship has been difficult.”
A significant concern with hexane is its role in creating reproductive damage. Studies show that hexane entering the body of a pregnant woman can pass through the placental barrier to injure the central nervous system of the unborn baby. From “Toxicological Profile for n-Hexane Draft for Public Comment May 2024”:
“The available information suggests that adverse neurological, respiratory, developmental, and reproductive effects are the most important health concerns related to exposure to n-hexane (Figures 1-1 and 1-2). Muscle atrophy and decreased body weight are also common findings after exposure to n-hexane in experimental animals, but they are possibly secondary to the neurotoxicity that results in muscle denervation and decreased ability to move.”
Research examining female workers exposed to hexane revealed the chemical to be an endocrine disruptor—chemicals that interfere with the endocrine system—a network of glands that produce all the hormones in your body. Studies showed the solvent caused ovarian damage through cell death, as well as disrupting the release of ovarian estrogen. In men, hexane was identified as causing testicular injury, impairing fertility. Moreover, your body breaks down hexane into 2,5-hexanedione, which stays put for days, and is slowly excreted through your urine. If you ingest food with hexane on a regular basis, whatever 2,5-hexanedione that’s excreted, is replaced by more hexane-containing foods you eat. And 2,5-hexanedione damages the dopaminergic neurons in the brain, which are the neurons producing dopamine in your body. This injury may contribute to developing Parkinson’s disease, a progressive, degenerative brain disorder.
Environment: Some amounts of hexane are released into the atmosphere during the food manufacturing process. This reacts with other pollutants in the air to form ozone, a component in smog, which is harmful to the environment and your health. Industries switched to using hexane as a solvent when benzene, a known carcinogen, was theoretically banned nearly 50 years ago. However, hexane in food is not regulated by the U.S. Food and Drug Administration (FDA) except in a few isolated cases, such as in the extraction of hops and spice oleoresins. Meanwhile, Europe’s version of the FDA, the European Food Safety Authority (EFSA), approved a plant-based hexane substitute called methyloxolane in 2022. The EFSA determined methyloxolane was safe to use as a solvent. This was the first step for methyloxolane to be applied to food production as a natural alternative to petroleum-based hexane. Laurence Jacques, managing director of the Minafin Group, a European business pushing for the use of methyloxolane as a replacement for hexane, explained:
“Hexane is banned from organic food (in the U.S. and Europe) and cosmetics (in Europe). It has been substituted in pharmaceutical production for 20 years (in Europe). And you won’t find any toxicological assessments of hexane. Hexane entered the food chain around World War II and never applied for an approval. The reason it is still in our food chain is that it is critical for food security. Every year, about 1.1. million tonnes of hexane are used by the food industry and this will continue unchallenged as long as there is no better alternative.”
Hexane has become important to food security because of its widespread use in food production. Its role as a solvent enables mass-scale industrial manufacturing of foodstuff, which includes a large variety of products. For example: The soy oil extracted with hexane is mixed with water to separate out soy lecithin, which is contained in infant formula (in addition, baby gets GMOs and herbicides), as well as breads, ice cream, supplements, and more. Soy bathed in hexane is used to create foods deemed healthy by some consumers, such as veggie burgers and soymilk. Jacques continued:
“As long as nobody shows that a clean dossier is possible, it is easy for all the other solvents to claim an alternative isn’t possible, the studies are too expensive. We want to show that it is possible for a solvent and it should be done. We did studies (for methyloxolane) on rats, baby rats, pregnant rats. For hexane, we are the rats.”
It’s probable you’ve been exposed to hexane on a regular basis because of its extensive use. In one study this was validated by examining a population of Italians who were not exposed to hexane through their work environment. It showed the general population had varying concentrations of hexane in their bodies, ranging from 0.3 to 0.8 milligrams per liter. And as the U.S. Agency for Toxic Substances and Disease Registry (ATSDR) states, “Since gasoline contains n-hexane, almost everyone is exposed to small amounts of n-hexane in the air.” N-hexane is the technical term for the type of hexane used in the industrial processes discussed in this article.
What does less than a milligram per liter of hexane in your body mean for your health? According to the American Conference of Governmental Industrial Hygienists (ACGIH), a nonprofit scientific organization focused on occupational and environmental health, a safe exposure limit for hexane in the workplace is at concentrations below five milligrams per liter. No standards outside of a work environment have been set, but ACGIH’s recommendation suggests the hexane levels that may be in your body are well below safety limits. Interestingly, the U.S. Department of Labor’s Occupational Safety and Health Administration (OSHA) set a safety limit ten times higher than ACGIH, although it stated:
“OSHA recognizes that many of its permissible exposure limits (PELs) are outdated and inadequate for ensuring protection of worker health. Most of OSHA’s PELs were issued shortly after adoption of the Occupational Safety and Health (OSH) Act in 1970, and have not been updated since that time.”
Decrease Your Susceptibility to the Dangers of Hexane
Your greatest vulnerability to hexane exposure comes from car fumes, as vehicle exhaust contains substantially more hexane than the trace amounts found in food oils and their associated products. Moreover, as you breathe in the chemical, it bypasses your liver, a key organ in your body’s detoxification process. The emissions from cars in Los Angeles, CA were found to contain 135 milligrams of hexane per liter, which is 27 times higher than the level ACGIH considers safe. Granted, L.A. is a large, urban, car-centric city; others will have varying results. In comparison, a variety of vegetable oils, including canola and sunflower, contained 42.6 micrograms per liter. 1 milligram equals 1,000 micrograms, so you can see vehicle exhaust is far more likely to cause damage to your body than hexane from food.
Knowing this, you may be extra observant and cautious about spending time near idling cars, or keeping your car’s windows open while pushing through heavy traffic. Perhaps this will influence where you take your kids to play (closer to nature; further from nearby automotive movement), or even have a role in helping you choose where to live. While it’s true that some things are hard to change, or seemingly out of your control, it’s also true that there are almost always steps you can take to improve any situation. While the fumes from car exhaust prove to be most unsafe, and loom over the environment, that only makes it more important to minimize hexane intake in every other area possible. One way you can do this is to pay close attention to what you eat and drink. Choose organic whenever possible, as organic products are legally prohibited from containing hexane. And while you’ve heard it said many times … read the ingredients in packaged foods.
Watch out for products claiming to be “natural,” “whole,” or “earth-friendly.” These items may contain hexane and other additives, as manufacturers can put such labels on any item they deem fit, with little FDA oversight. Remember, you won’t see “hexane” on the label—look for the oils and fillers! One example is soy protein isolate, a highly-processed plant extract that uses hexane to separate out the protein content from soybeans. This additive is contained in snack foods, including protein powders and shakes. So if you blindly eat processed and packaged foods, ingesting hexane may be virtually unavoidable. It can be found in brands of ice cream, ready made pizzas, and varieties of instant noodles, etc., which contain palm oil, extracted with hexane.
Sticking with organic-only cuisine can be challenging, especially when eating at restaurants and grocery store hot bars. Simple tips to help reduce exposure include staying away from fried foods, since these are typically cooked in hexane-manufactured oils. Avoid cuisine made with or containing soy, which means steering clear of meat alternatives, such as soy burgers and sausages, and conventional tofu. If you want to gain more traction in upgrading your health, and you love to eat in restaurants, it calls for speaking up, which at times can feel uncomfortable. Here’s an example of a conversation you might have with your server:
“Hi there, do you know what type of oil is used in the salmon dish?” (Of course this is after determining whether the salmon is farm-raised or wild). “Oh, olive oil, really? That’s great. Do you happen to know if it’s extra virgin olive oil or a blend?” “You need to go ask the chef … okay no problem.” Server returns and gives you the information. And you reply, “Ah, I see, it’s actually a blend; good to know, thanks. I’ve heard of that “90/10,”—90% canola, 10% olive oil. I’m going to pass on that dish.” In addition to learning if the oil a blend, there is another step. If it’s not a blend—just plain ol’ olive oil, but not extra virgin, you will be consuming “olive pomace oil”—the bottom of the barrel (quite literally), lowest quality, extracted with hexane from the pulp that’s left over after the initial squeeze. You could call ahead and ask instead of at the table, though sometimes it’s harder to get accurate information. Alternatively, you could not inquire at restaurants, eat what tastes good and brings you joy, and be most mindful in your own kitchen. The choice is yours, and to each their own. If you don’t feel like having a “Portlandia” moment, it’s completely understandable.
When purchasing oil to add to meals (for cooking or drizzling), look for labels with terms such as “expeller-pressed,” “cold-pressed,” or “unrefined.” Cold-pressed oils are best because they are minimally processed, without the application of heat. Extra virgin olive oil and avocado oil use the cold-pressed method. Since cold and expeller-pressed procedures are less efficient than extracting with hexane, be aware of the higher price tags. In contrast, if the product does not specifically state pressed or extra virgin, you can assume a solvent such as hexane was used. A tool you might find of interest is the Organic Soy Report and Scorecard issued by the Cornucopia Institute, a nonprofit consumer watchdog group dedicated to food and agricultural topics. The report includes insights to help you find healthy, hexane-free food.
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Published on July 25, 2024.
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