Non-Stick Cookware and Food Grade Plastics
Risks to Health
There has not been much scientific study of the risks to health of eating food that has been cooked or, when warm put, in non-stick coated cookware or plastics. Scientists have proven that chemicals and microplastics leach into food and beverages from these types of “food contact materials”. However, many of the leached chemicals have not been identified and, therefore, not studied for health effects. Even for most of the identified chemicals, the health effects are unknown.
When it comes to ingested toxins, I am the canary in the coal mine. I have been diagnosed with a genetic inability to metabolize toxins in my digestive system. I experience symptoms within a few days of ingestion, including nausea and diarrhea which is sometimes bloody. Each time I experience these symptoms, I use the elimination diet to identify the cause. Within a few days after removing the cause from my diet, the symptoms end.
I was able to get a genetic diagnosis from OneOme RightMed® because medical experts have observed that, in a subset of patients, a normal recommended dose of any oral medication has the toxic effects of an overdose. Research identified some of the genes responsible for metabolization of ingested toxins in the digestive system and the gene variants that render these genes ineffective. When these genes are effective, they typically neutralize about 80% of any oral drug, allowing only 20% into the blood stream. When these genes are not fully effective, they allow a higher dose of the drug into the blood stream, causing side effects and, in some cases like mine, an overdose.
Though the research was focused on oral medication, which is toxic, it applies equally to any ingested toxin. I have identified the non-medication causes of my symptoms. They include food-cooking equipment with coatings that are non-stick and food-grade plastics, especially from their contact with warm or hot food or beverage.
In this blog, I focus on manufactured toxins. I use the general term of “toxins” even though I know that the technical term for manufactured toxins is “toxicants”. The word “toxins” refers to the toxins that naturally occur in some foods, mostly vegetables.
I’ve researched food safety information relating to these food contact materials. The science is weak for several reasons.
First, the non-stick coatings and food grade plastics entered the market about sixty to eighty years ago, when regulation of their safety was weak to non-existent. They have acquired ubiquity because, if there are any health consequences, they are too remote in time to be traced back to the use of these manufactured toxins, especially as these manufactured food contact materials contain thousands of chemicals. And it is near impossible to determine this causation independently of the impacts on health by other manufactured products in common use such as soaps, shampoos, cosmetics, household cleaning products, etc. I have been able to determine the causation of my symptoms only because they occur within a few days of my ingestion of food that was cooked or stored in these manufactured food contact materials; and by following an elimination diet and keeping a food and symptom diary.
Second, the precautionary principle is not applied. These products came to market before the precautionary principle was adopted. That principle dictates that, when a manufactured product raises threats of harm to human health, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically. There is an absence of evidence of a causal connection between these substances and any specific health condition because this question has not been adequately researched.
Third, what little research has been done focuses on these products in their newly manufactured conditions. There is little research on the safety of their cumulative uses. Non-stick coated cookware and plastic containers are often re-used for many years.
Fourth, the research focuses on the safety of individual chemical substances. That does not reflect the common uses. Food may be cooked in non-stick cookware or microwave plastic, then eaten on styrofoam plates or takeout containers with plastic cutlery, and then stored and reheated in plastic containers. And the beverage drunk with the food may have been served in a plastic, styrofoam, or plastic-lined paper cup. The common human use of these products exposes people to a cocktail of thousands of chemicals. There is no research into the health effects of these chemical cocktails.
I present what I have found out.
Teflon and other non-stick coatings used for cooking food
The chemical name of Teflon is polytetrafluoroethylene (PTFE). Since DuPont’s patent expired circa 1980, non-stick coatings have become ubiquitous in domestic and commercial cookware and bakeware. Most commercially baked food sold in grocery stores has been baked in non-stick bakeware, including many processed foods that are labelled “organic”.
In 2013 one of the ingredients – perfluorooctanoic acid (PFOA) – was removed because of health risks. Do not use any non-stick cookware manufactured prior to 2013.
Non-stick coatings are still made of PFAS (per- and polyfluoroaklyl substances), which are not fully understood. The American Food and Drug Administration reports that, even though PFAS have been in use for food preparation for over 80 years, validated methods to test for PFAS in foods have only recently been developed. Risks to human health have not yet been evaluated. The FDA has begun to test foods purchased at grocery stores but have not reported test results. The FDA continues to approve PFAS for food use if the manufacturer proves that “available data and information demonstrate that there is a reasonable certainty of no harm under the intended conditions of use.” Given the lack of “available data and information” this standard is not comforting. And “reasonable certainty” is not as high a standard as the “scientific certainty” standard of proof used by the scientific community to determine cause and effect. The regulator does not apply the precautionary principle.
HealthLine reports that non-stick coatings break down at temperatures above 500°F (260°C). They are presumed safe for food because recommended food cooking temperatures are a little bit lower (rarely more than 400°F (205°C). This safety assessment is based on three assumptions: (1) that most domestic and commercial cooks do not exceed the recommended cooking temperatures; (2) that the non-stick coating releases no toxins, not even after repeated use; and (3) all consumers have the genetic ability to metabolize a certain quantity of ingested toxins.
Cooking temperature: HealthLine reports that, when food is cooked at a temperature above 500°F (260°C), the non-stick coating begins to break down releasing chemicals into the food and the air.
Who uses a thermometer to check the surface temperature of their pan while cooking? Many people cook at higher-than-recommended temperatures.
Non-stick cookware is preferred by those who have struggled to clean stuck-on food from stainless steel cookware. Food sticks to stainless steel only because the cooking temperatures are too high and because most cooks do not use enough fat to prevent sticking. Time pressures induce people to cook at high temperatures because it is faster.
Also, some common cooking practices use high temperatures. For example, pre-heating a pan without food causes the pan to quickly become very hot. High temperatures are used to “brown” meat and to caramelize onions. And food is broiled close to the high heat source above. Restaurant cooks entertain guests with a flame in the stir-fry pan.
Regulators should require safety evidence based on the normal cooking uses by ordinary people, rather than the manufacturers’ experiments which control the cooking temperature.
Manufacturing quality and repeated use: HealthLine reports that fabrication of non-stick coatings is difficult. Many non-stick coated cookware is made in countries that do not have robust regulatory oversight of manufacturers. Even in those with more effective regulators, the approvals are based on the first use when the non-stick coating is new.
With every use, non-stick particles flake off even the best-quality cookware with no visible damage. The Food Packaging Forum reports that cooking in non-stick cookware may lead to the release of thousands of micro- and nanoplastics into the food and that old pans release more and bigger particles than new ones. WebMD reports that this does not cause any known health problems. This report reflects the scientific difficulty of proving that an ingested thing causes a particular health effect. Long-term health effects cannot be proven with scientific certainty. The best evidence would be statistical evidence from a long-term epidemiological study but I have never seen questions about cooking equipment on a food questionnaire in this type of study. And the report makes no mention of people who have a genetic inability to metabolize ingested toxins.
Some labels on non-stick cookware warn to discontinue use if the non-stick surface is scratched because the damage releases toxins into the food. I have observed many domestic meals cooked in damaged non-stick pans.
Health: So why do I get bloody diarrhea from food cooked in a new non-stick pan at recommended temperatures? Because it always emits chemicals and flakes off particles even when first used.
Teflon warns cooks not to keep pet birds in the kitchen because hot Teflon can release fumes that are toxic to birds. Those toxic fumes permeate the food and make me ill.
Teflon and other non-stick coatings came to market before the precautionary principle was adopted. That principle would require manufacturers to prove it is not harmful to human health. Instead, non-stick coatings continue in common use until independent and underfunded researchers prove it is harmful. The American Agency for Toxic Substances and Disease Registry mention animal studies that have identified potential harms from PFAS including harms to the liver and immune system.
Even if you do not suffer any noticeable symptoms, you are ingesting toxins when you consume food that was cooked in non-stick coated cookware. And these toxins are likely accumulating in your body, along with all the others that you ingest and inhale. The health risks are unknown.
Food Grade Plastics
I suffer diarrhea, sometimes bloody, after eating any food or beverage that, when warm or hot, was in contact with plastic, including most food-grade plastics. I suffer these effects from microwave plastics, plastic food containers, plastic wrap, Styrofoam, the plastic linings of cans, jar lids and paper take out containers, including coffee cups, etc. The only plastic that does not (yet) have this effect on me is the plastic used to make electric kettles.
All plastics are made from petroleum. Food-grade plastics are regulated but, given that they entered the market more than 80 years ago, the science on toxicity is weak. Scientists have not been able to identify most of the 1000s of toxins that leach from food-grade plastics. We do not know the health effects of most of these individual toxins, nor the combined and cumulative health effects of all of them over time.
The European Food Safety Authority allows overall migration into each kilogram of food from food contact materials of up to 60 mg of all substances. They have specific limits for some individual substances.
The manufacturers’ tests for food safety are done on new plastic products. They do not test the risks of repeated use of a plastic container nor an individual’s cumulative exposure to microtoxins from the many plastics that are used with food. The Food Packaging Forum reports that cumulative health effects are unknown.
The Plastic Health Coalition reports that there is still a limited understanding of the extent of our exposure to microplastics. They identify studies confirming that microplastics are detected in human faeces, which proves they are ingested, but whether they can escape from our intestines into our blood stream is unknown. The Coalition notes the lack of scientific study of the potential presence of microplastics in our bloodstream and other parts of our bodies. Without understanding exposure, scientists cannot determine risk.
A 2019 German study tested for toxicity in a variety of common food contact plastics purchased in grocery stores. The food contents were removed, and the plastics were cleaned before testing. I presume this study did not test the food contents for toxicity because they would not be able to prove that the plastic containers were the source, rather than a pre-packaging source such as pesticides or contamination during food processing. After heating then cooling the cleaned plastics, the researchers found that most of them release toxins. They noted the complexity of plastics and how little is known about their health risks. Toxicological data is unavailable for most of the known chemicals in food contact plastics.
These researchers also tested products that are proposed as replacements for plastic and found them to be more toxic than the plastics.
A 2021 follow-up study found that all commonly used food grade plastics leach toxins into water – that several thousand chemicals migrate from plastics – but the researchers could identify only 211 of them. The plastics were immersed in pure water at 40°C (104°F) for 10 days in the dark. The researchers did not test the extent of toxins released into hotter beverages or into food. Also, the tests were done on new plastics – they did not test re-used plastics.
A 2022 literature review endeavoured to identify and list all food contact chemicals found in a variety of food contact materials (including plastics, rubber and silicone). 65% of the chemicals that they identified were not previously known to be used in food contact materials. They found 1975 chemicals in food contact plastics. And they reported that there has been no systematic overview of the chemicals that migrate into food.
Another literature review in 2022 reported that recycled plastics pose additional risks because additional chemicals can be introduced in the process of use and recycling. They also noted that some foods are known to draw chemicals from plastic; specifically noting fats.
The Food Packaging Forum reports that liquid, that was heated by microwave in a microwavable plastic container, contained more than one million particles of micro plastic per litre. And they reported that chemical migration from the container to the food increases with re-use of the container to heat food in a microwave.
Phthalates are added to plastic to make it more flexible. Food plastics that might contain phthalates include plastic wrappings, clam shells, take-out containers, linings of paper take-out containers, water bottles, drinking straws, gaskets in jars, etc. Whether a food plastic contains phthalates is not on the label but should be presumed in any plastics no. 3, 6 and 7. There is no way to know except by asking the manufacturer of the container. Phthalates leach from the containers even into cold food. Heat increases the quantity leached. In addition, acidic and fatty foods draw out more phthalates. Numerous studies have found phthalates in the urine of people. The debates continue as to its health effects. Here is the best advice I can find to avoid phthalates, and the Consumer Reports article, and a study on the effects of phthalates on the brain development of children.
Many take out containers and food storage containers, like Tupperware and yogurt containers, are no. 5 (PP – Polypropylene). Also, food-grade silicone is not just silica (sand) – silicone contains polymer, aka, PP Polypropylene. As PP has a high melting point, it is typically labelled safe for dishwasher and microwave use. However, it cannot be used at high temperatures because it is highly flammable and prone to thermal expansion, which is why it is labelled not for use in the oven or on the stovetop. It is also susceptible to UV degradation, oxidation, and damage from chlorinated solvents. That is, it does not weather well. Light, oxygen and chlorinated water can cause it to degrade. Single-use polymers contain biodegradable additives to accelerate their degradation. The Food Packaging Forum reports that micro-plastics are released into the food from PP take-out containers and PP drinking containers. They have not analyzed other PP food containers.
Polystyrene (PS – No 6) can be made into Styrofoam or a hard plastic, which is used for take-out food containers, including coffee cups. Plastic Wrap and some food storage lids are Low-density polyethylene (LDPE – No 4). Some plastic wraps are made of polyvinyl chloride (PVC – No 3). Water bottles are made of Polyethylene terephthalate (PETE or PET – No 1). The Food Packaging Forum reports that these materials leach tiny plastic particles into every hot beverage or food – the hotter the food, the more plastic particles are released. Their research found that occasional and frequent consumption from these plastic containers could cause the alterations of composition, structure and functional pathways of the gut and oral microbiota, which could result in gastrointestinal dysfunction and cough. Further, they report that PS particles can be internalized in the human colon cells and lead to metabolic changes increasing the risk of cancer.
A 2022 American study found that plastic-lined takeout coffee cups and nylon tea bags release trillions of sub-100 nm nanoparticles per litre into water during normal use; even more if the water is hot. It found that particles released into water from a single 300 mL hot beverage cup equate to one particle for every seven cells in the human body in a size range available for cellular uptake. The Food Packaging Forum and McGill University report that billions of polyethylene terephthalate (PET) particles from plastic tea bags leach into a cup of tea.
The cans that contain food and beverages are lined with plastic. And jar lids are lined plastisol, often with a silicone seal adjacent to the jar rim. Up until recently, many of these plastics contained bisphenol A (BPA), but that has been replaced with bisphenol S and F, which HealthLine reports have the same toxic effects. BecauseHealth.org reports that other can linings have been replaced with oleoresins, PVC, polystyrene and other polymers. The plastisol of jar lids is PVC or another polymer. These plastics have not been adequately studied for food safety.
Conclusion
There is no law requiring food labels to identify the nature of the cookware used in processing food. You must presume that all commercially prepared foods are cooked, baked or roasted in non-stick coated equipment. Even chocolates are poured into non-stick molds (unnecessarily – chocolate’s natural fat prevents it from sticking to a stainless-steel mold).
Labelling laws do not require a list of the chemicals in any food-grade plastic. Many are unknown. The numbers in the triangles are for the plastic recyclers, so that they can recycle similar plastics together. The numbers say nothing about health risks.
It’s not even buyer beware because health-risk information is not available. We are all guinea pigs in a big experiment.
The bottom line: Buy raw food and cook it yourself in stainless steel or oven-proof glass cookware.
When it comes to ingested toxins, I am the canary in the coal mine. I have been diagnosed with a genetic inability to metabolize toxins in my digestive system. I experience symptoms within a few days of ingestion, including nausea and diarrhea which is sometimes bloody. Each time I experience these symptoms, I use the elimination diet to identify the cause. Within a few days after removing the cause from my diet, the symptoms end.
I was able to get a genetic diagnosis from OneOme RightMed® because medical experts have observed that, in a subset of patients, a normal recommended dose of any oral medication has the toxic effects of an overdose. Research identified some of the genes responsible for metabolization of ingested toxins in the digestive system and the gene variants that render these genes ineffective. When these genes are effective, they typically neutralize about 80% of any oral drug, allowing only 20% into the blood stream. When these genes are not fully effective, they allow a higher dose of the drug into the blood stream, causing side effects and, in some cases like mine, an overdose.
Though the research was focused on oral medication, which is toxic, it applies equally to any ingested toxin. I have identified the non-medication causes of my symptoms. They include food-cooking equipment with coatings that are non-stick and food-grade plastics, especially from their contact with warm or hot food or beverage.
In this blog, I focus on manufactured toxins. I use the general term of “toxins” even though I know that the technical term for manufactured toxins is “toxicants”. The word “toxins” refers to the toxins that naturally occur in some foods, mostly vegetables.
I’ve researched food safety information relating to these food contact materials. The science is weak for several reasons.
First, the non-stick coatings and food grade plastics entered the market about sixty to eighty years ago, when regulation of their safety was weak to non-existent. They have acquired ubiquity because, if there are any health consequences, they are too remote in time to be traced back to the use of these manufactured toxins, especially as these manufactured food contact materials contain thousands of chemicals. And it is near impossible to determine this causation independently of the impacts on health by other manufactured products in common use such as soaps, shampoos, cosmetics, household cleaning products, etc. I have been able to determine the causation of my symptoms only because they occur within a few days of my ingestion of food that was cooked or stored in these manufactured food contact materials; and by following an elimination diet and keeping a food and symptom diary.
Second, the precautionary principle is not applied. These products came to market before the precautionary principle was adopted. That principle dictates that, when a manufactured product raises threats of harm to human health, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically. There is an absence of evidence of a causal connection between these substances and any specific health condition because this question has not been adequately researched.
Third, what little research has been done focuses on these products in their newly manufactured conditions. There is little research on the safety of their cumulative uses. Non-stick coated cookware and plastic containers are often re-used for many years.
Fourth, the research focuses on the safety of individual chemical substances. That does not reflect the common uses. Food may be cooked in non-stick cookware or microwave plastic, then eaten on styrofoam plates or takeout containers with plastic cutlery, and then stored and reheated in plastic containers. And the beverage drunk with the food may have been served in a plastic, styrofoam, or plastic-lined paper cup. The common human use of these products exposes people to a cocktail of thousands of chemicals. There is no research into the health effects of these chemical cocktails.
I present what I have found out.
Teflon and other non-stick coatings used for cooking food
The chemical name of Teflon is polytetrafluoroethylene (PTFE). Since DuPont’s patent expired circa 1980, non-stick coatings have become ubiquitous in domestic and commercial cookware and bakeware. Most commercially baked food sold in grocery stores has been baked in non-stick bakeware, including many processed foods that are labelled “organic”.
In 2013 one of the ingredients – perfluorooctanoic acid (PFOA) – was removed because of health risks. Do not use any non-stick cookware manufactured prior to 2013.
Non-stick coatings are still made of PFAS (per- and polyfluoroaklyl substances), which are not fully understood. The American Food and Drug Administration reports that, even though PFAS have been in use for food preparation for over 80 years, validated methods to test for PFAS in foods have only recently been developed. Risks to human health have not yet been evaluated. The FDA has begun to test foods purchased at grocery stores but have not reported test results. The FDA continues to approve PFAS for food use if the manufacturer proves that “available data and information demonstrate that there is a reasonable certainty of no harm under the intended conditions of use.” Given the lack of “available data and information” this standard is not comforting. And “reasonable certainty” is not as high a standard as the “scientific certainty” standard of proof used by the scientific community to determine cause and effect. The regulator does not apply the precautionary principle.
HealthLine reports that non-stick coatings break down at temperatures above 500°F (260°C). They are presumed safe for food because recommended food cooking temperatures are a little bit lower (rarely more than 400°F (205°C). This safety assessment is based on three assumptions: (1) that most domestic and commercial cooks do not exceed the recommended cooking temperatures; (2) that the non-stick coating releases no toxins, not even after repeated use; and (3) all consumers have the genetic ability to metabolize a certain quantity of ingested toxins.
Cooking temperature: HealthLine reports that, when food is cooked at a temperature above 500°F (260°C), the non-stick coating begins to break down releasing chemicals into the food and the air.
Who uses a thermometer to check the surface temperature of their pan while cooking? Many people cook at higher-than-recommended temperatures.
Non-stick cookware is preferred by those who have struggled to clean stuck-on food from stainless steel cookware. Food sticks to stainless steel only because the cooking temperatures are too high and because most cooks do not use enough fat to prevent sticking. Time pressures induce people to cook at high temperatures because it is faster.
Also, some common cooking practices use high temperatures. For example, pre-heating a pan without food causes the pan to quickly become very hot. High temperatures are used to “brown” meat and to caramelize onions. And food is broiled close to the high heat source above. Restaurant cooks entertain guests with a flame in the stir-fry pan.
Regulators should require safety evidence based on the normal cooking uses by ordinary people, rather than the manufacturers’ experiments which control the cooking temperature.
Manufacturing quality and repeated use: HealthLine reports that fabrication of non-stick coatings is difficult. Many non-stick coated cookware is made in countries that do not have robust regulatory oversight of manufacturers. Even in those with more effective regulators, the approvals are based on the first use when the non-stick coating is new.
With every use, non-stick particles flake off even the best-quality cookware with no visible damage. The Food Packaging Forum reports that cooking in non-stick cookware may lead to the release of thousands of micro- and nanoplastics into the food and that old pans release more and bigger particles than new ones. WebMD reports that this does not cause any known health problems. This report reflects the scientific difficulty of proving that an ingested thing causes a particular health effect. Long-term health effects cannot be proven with scientific certainty. The best evidence would be statistical evidence from a long-term epidemiological study but I have never seen questions about cooking equipment on a food questionnaire in this type of study. And the report makes no mention of people who have a genetic inability to metabolize ingested toxins.
Some labels on non-stick cookware warn to discontinue use if the non-stick surface is scratched because the damage releases toxins into the food. I have observed many domestic meals cooked in damaged non-stick pans.
Health: So why do I get bloody diarrhea from food cooked in a new non-stick pan at recommended temperatures? Because it always emits chemicals and flakes off particles even when first used.
Teflon warns cooks not to keep pet birds in the kitchen because hot Teflon can release fumes that are toxic to birds. Those toxic fumes permeate the food and make me ill.
Teflon and other non-stick coatings came to market before the precautionary principle was adopted. That principle would require manufacturers to prove it is not harmful to human health. Instead, non-stick coatings continue in common use until independent and underfunded researchers prove it is harmful. The American Agency for Toxic Substances and Disease Registry mention animal studies that have identified potential harms from PFAS including harms to the liver and immune system.
Even if you do not suffer any noticeable symptoms, you are ingesting toxins when you consume food that was cooked in non-stick coated cookware. And these toxins are likely accumulating in your body, along with all the others that you ingest and inhale. The health risks are unknown.
Food Grade Plastics
I suffer diarrhea, sometimes bloody, after eating any food or beverage that, when warm or hot, was in contact with plastic, including most food-grade plastics. I suffer these effects from microwave plastics, plastic food containers, plastic wrap, Styrofoam, the plastic linings of cans, jar lids and paper take out containers, including coffee cups, etc. The only plastic that does not (yet) have this effect on me is the plastic used to make electric kettles.
All plastics are made from petroleum. Food-grade plastics are regulated but, given that they entered the market more than 80 years ago, the science on toxicity is weak. Scientists have not been able to identify most of the 1000s of toxins that leach from food-grade plastics. We do not know the health effects of most of these individual toxins, nor the combined and cumulative health effects of all of them over time.
The European Food Safety Authority allows overall migration into each kilogram of food from food contact materials of up to 60 mg of all substances. They have specific limits for some individual substances.
The manufacturers’ tests for food safety are done on new plastic products. They do not test the risks of repeated use of a plastic container nor an individual’s cumulative exposure to microtoxins from the many plastics that are used with food. The Food Packaging Forum reports that cumulative health effects are unknown.
The Plastic Health Coalition reports that there is still a limited understanding of the extent of our exposure to microplastics. They identify studies confirming that microplastics are detected in human faeces, which proves they are ingested, but whether they can escape from our intestines into our blood stream is unknown. The Coalition notes the lack of scientific study of the potential presence of microplastics in our bloodstream and other parts of our bodies. Without understanding exposure, scientists cannot determine risk.
A 2019 German study tested for toxicity in a variety of common food contact plastics purchased in grocery stores. The food contents were removed, and the plastics were cleaned before testing. I presume this study did not test the food contents for toxicity because they would not be able to prove that the plastic containers were the source, rather than a pre-packaging source such as pesticides or contamination during food processing. After heating then cooling the cleaned plastics, the researchers found that most of them release toxins. They noted the complexity of plastics and how little is known about their health risks. Toxicological data is unavailable for most of the known chemicals in food contact plastics.
These researchers also tested products that are proposed as replacements for plastic and found them to be more toxic than the plastics.
A 2021 follow-up study found that all commonly used food grade plastics leach toxins into water – that several thousand chemicals migrate from plastics – but the researchers could identify only 211 of them. The plastics were immersed in pure water at 40°C (104°F) for 10 days in the dark. The researchers did not test the extent of toxins released into hotter beverages or into food. Also, the tests were done on new plastics – they did not test re-used plastics.
A 2022 literature review endeavoured to identify and list all food contact chemicals found in a variety of food contact materials (including plastics, rubber and silicone). 65% of the chemicals that they identified were not previously known to be used in food contact materials. They found 1975 chemicals in food contact plastics. And they reported that there has been no systematic overview of the chemicals that migrate into food.
Another literature review in 2022 reported that recycled plastics pose additional risks because additional chemicals can be introduced in the process of use and recycling. They also noted that some foods are known to draw chemicals from plastic; specifically noting fats.
The Food Packaging Forum reports that liquid, that was heated by microwave in a microwavable plastic container, contained more than one million particles of micro plastic per litre. And they reported that chemical migration from the container to the food increases with re-use of the container to heat food in a microwave.
Phthalates are added to plastic to make it more flexible. Food plastics that might contain phthalates include plastic wrappings, clam shells, take-out containers, linings of paper take-out containers, water bottles, drinking straws, gaskets in jars, etc. Whether a food plastic contains phthalates is not on the label but should be presumed in any plastics no. 3, 6 and 7. There is no way to know except by asking the manufacturer of the container. Phthalates leach from the containers even into cold food. Heat increases the quantity leached. In addition, acidic and fatty foods draw out more phthalates. Numerous studies have found phthalates in the urine of people. The debates continue as to its health effects. Here is the best advice I can find to avoid phthalates, and the Consumer Reports article, and a study on the effects of phthalates on the brain development of children.
Many take out containers and food storage containers, like Tupperware and yogurt containers, are no. 5 (PP – Polypropylene). Also, food-grade silicone is not just silica (sand) – silicone contains polymer, aka, PP Polypropylene. As PP has a high melting point, it is typically labelled safe for dishwasher and microwave use. However, it cannot be used at high temperatures because it is highly flammable and prone to thermal expansion, which is why it is labelled not for use in the oven or on the stovetop. It is also susceptible to UV degradation, oxidation, and damage from chlorinated solvents. That is, it does not weather well. Light, oxygen and chlorinated water can cause it to degrade. Single-use polymers contain biodegradable additives to accelerate their degradation. The Food Packaging Forum reports that micro-plastics are released into the food from PP take-out containers and PP drinking containers. They have not analyzed other PP food containers.
Polystyrene (PS – No 6) can be made into Styrofoam or a hard plastic, which is used for take-out food containers, including coffee cups. Plastic Wrap and some food storage lids are Low-density polyethylene (LDPE – No 4). Some plastic wraps are made of polyvinyl chloride (PVC – No 3). Water bottles are made of Polyethylene terephthalate (PETE or PET – No 1). The Food Packaging Forum reports that these materials leach tiny plastic particles into every hot beverage or food – the hotter the food, the more plastic particles are released. Their research found that occasional and frequent consumption from these plastic containers could cause the alterations of composition, structure and functional pathways of the gut and oral microbiota, which could result in gastrointestinal dysfunction and cough. Further, they report that PS particles can be internalized in the human colon cells and lead to metabolic changes increasing the risk of cancer.
A 2022 American study found that plastic-lined takeout coffee cups and nylon tea bags release trillions of sub-100 nm nanoparticles per litre into water during normal use; even more if the water is hot. It found that particles released into water from a single 300 mL hot beverage cup equate to one particle for every seven cells in the human body in a size range available for cellular uptake. The Food Packaging Forum and McGill University report that billions of polyethylene terephthalate (PET) particles from plastic tea bags leach into a cup of tea.
The cans that contain food and beverages are lined with plastic. And jar lids are lined plastisol, often with a silicone seal adjacent to the jar rim. Up until recently, many of these plastics contained bisphenol A (BPA), but that has been replaced with bisphenol S and F, which HealthLine reports have the same toxic effects. BecauseHealth.org reports that other can linings have been replaced with oleoresins, PVC, polystyrene and other polymers. The plastisol of jar lids is PVC or another polymer. These plastics have not been adequately studied for food safety.
Conclusion
There is no law requiring food labels to identify the nature of the cookware used in processing food. You must presume that all commercially prepared foods are cooked, baked or roasted in non-stick coated equipment. Even chocolates are poured into non-stick molds (unnecessarily – chocolate’s natural fat prevents it from sticking to a stainless-steel mold).
Labelling laws do not require a list of the chemicals in any food-grade plastic. Many are unknown. The numbers in the triangles are for the plastic recyclers, so that they can recycle similar plastics together. The numbers say nothing about health risks.
It’s not even buyer beware because health-risk information is not available. We are all guinea pigs in a big experiment.
The bottom line: Buy raw food and cook it yourself in stainless steel or oven-proof glass cookware.
