Part 1 of the holiday spring cleaning series outlined the travails of the urban environmentalist as she or he navigates through the toxic nasties present around the home. Besides seriously affecting human health, our air and water, these synthetics also place a heavy burden on the environment. Read more here.
This post is going to focus on the 3 Nasty Ps that are insidiously present in our homes entering innocuously through the food or products we buy.
1. PTFE ( most common brand name is Teflon)
Polytetrafluroethylene (PTFE) is a synthetic polymer used in many applications including non-stick coatings applied on kitchenware. This was developed by DuPont and patented in 1941. Used initially to coat valves and seals in pipes that held very reactive chemicals like uranium hexafluoride, Teflon (as PTFE was commonly called), soon graduated into kitchenware and a French cookware company introduced its first non stick pan in 1954.
Using PTFE (Teflon) coated cookware comes with some serious health hazards:
Pyrolysis at temperatures at or above 200 deg C :
Teflon which is stable at low temperatures starts to degrade at temperatures around 250 deg C and decomposes at 350 deg C. The by-products that emanate during this degradation can give you flu-like polymer fume fever – . This makes frying of certain food groups like meat (usually between 200 – 260 deg C) extremely hazardous in non-stick cookware.
Certain oils like safflower oil and olive oil have a high smoke point, which means that if these oils are used for frying / cooking in a non stick dish, you would unknowingly be exposing yourself to a much greater health risk.
Rapid thermal degradation at lower temperatures :
Tests conducted by the Environmental Working Group (EWG) estimate a Teflon coated pan can exceed the safe temperature in just 2 – 5 minutes on a conventional stove top. A Teflon pan reaches 383 deg C in just over 3 minutes on a stove top. Studies from DuPont, the maker of Teflon show that Teflon releases toxic particulate gases at 240 deg C. At 360 deg C, Teflon coated pans release atleast 6 toxic gases including 2 carcinogens, 2 global pollutants and MFA (a compound lethal to human beings even in low doses).
At 538 deg C, a temperature DuPont scientists admit are reached on conventional stove tops, non stick coatings break down to a chemical warfare agent known as PFIB and an analogue of Phosgene, used in WW2 as nerve gas.
This is an incomplete list of the toxic gases and particulate matter generated during the thermal degradation of Teflon:
1. TFE (Tetraflouroethylene)
2. HFP (Hexa Flouropropene)
3. OFCB – Octaflourocyclobutane
4. PFIB – Perflouroisobutane – a chemical agent 10 times more toxic than Phosgene
5. Carbonyl Fluoride – The fluorine analogue of Phosgene
6. TFA – Triflouroacetic acid
7. Triflouroacetic acid fluoride
8. Perflouro butane
9. SiF4 (Silicon tetra fluoride)
10. HF Hydrofluoric acid – a very corrosive gas
11. Monoflouro acetic Acid – MFA – can kill human beings at low doses
Human beings exposed to these Teflon origin fumes develop what is called “Polymer Fume fever” – a flu like illness especially in poorly ventilated areas. Typical symptoms include fever, chills, nausea, headaches, muscle and joint pain and fatigue.
Health fallouts of using or working in factories that manufacture Teflon coated products:
Six studies point to an increased risk of heart attacks and strokes on exposure to the Teflon chemical. A study also showed that workers exposed to Teflon showed a higher risk of elevated cholesterol.
In more than one study, Teflon has been linked to multiple cancers in male and female mice with statistical significance and relevance for human beings.
Mammary tumours were found to have a significant increase in animal studies where the group given a high dose of Teflon had more than double of these rates.
Testicular and pancreatic cancers also showed a statistically significant, elevated risk from exposure to Teflon.
A series of studies show that Teflon tends to suppress the immune system response – in this, there is NO KNOWN SAFE DOSE of Teflon.
These by-products of Thermal degradation of teflon are extremely persistent in the environment and some of these have no known degradation methods.
Who makes PTFE (brand name Teflon) and where can I find it around my home?
The DuPont company owns the registered trademark , Teflon, and has co-branded products across industries that use Teflon. Besides DuPont, a huge list of manufacturers exist that produce PTFE right in India and across the world. PTFE is found in a wide and bewildering array of products including:
1. Non stick cookware
2. Nail polish – to achieve a smooth surface that does not crack
3. Hair styling equipment – hair straighteners and curling irons
4. Windshield wiper blades – to help the surface stay smooth enough to glide across the windshield
5. Fabric and carpet protection that is labelled as stain / spill resistant
6. Chemical and steel industries – used to coat machine parts that commonly come in contact with highly corrosive materials
Perflurooctanoic acid (PFOA) is used as a surfactant in the polymerisation of many polymers including the above mentioned PTFE (Teflon) and Gore-Tex.
PFOA is a super villain even for those resigned to the Lex Luthor that is PTFE. Besides persisting indefinitely in the environment, and being both toxic and carcinogenic to animals, it has been universally found in extremely low trace amounts in the blood of atleast 98% of the US population and in 100% of the US newborn population.
Exposure to PFOA has been associated with increased cholesterol and uric acid levels and there has been a correlation between elevated PFOA levels in the blood and increased risk of chronic kidney disease.
Because of its widespread applications, PFOA has been used in many applications which need water or oil repellent properties – for example in wax coated paper that is used to wrap French fries , pizza boxes, sweets , sandwiches or coated paper used in microwave popcorn bags. Besides this it is used in dental floss, apparel or fabric that are sold on a “stain guard” claim, floor wax and wax removers, sealants used for stone, tile or wood, and non stick cookware.
There are currently no labelling requirements that manufacturers need to follow to declare the presence of PFOA in their packaging.
PFOA is part of a broad stream of chemicals called PFCs or Perflourocarbons – When PFCs are heated, they break down into compounds which are assimilated into the bloodstream through the food we eat.
Health hazards of PFOA
PFOA is a suspect carcinogen, liver, immune system and developmental toxin, and also alters hormones in our body like the thyroid hormone.
The developmental toxicity effects seen in animal studies include low birth weight, developmental delays, endocrine disruption and neo natal mortality.
Blood serum levels of PFOA were associated with an increased risk of infertility in human beings. It is also associated with ADHD in a study among US children aged between 12 – 15.
Attempted Ban on carcinogenic food packaging
An attempt was made in 2008 in California to regulate PFOA in food packaging. If approved, this would have banned PFOA, PFOD, and seven or more related fluorinated suspect carcinogenic compounds form food packing from 2010.
Unfortunately, severe lobbying from the industry led to this bill being shelved.
Phase out of PFOA
In 2006, eight companies including DuPont, agreed to eliminate PFOA from the Teflon manufacturing process. The voluntary pact, drafted by EPA, asked companies to reduce manufacturing emissions of PFOA by 95% by 2010, and to reduce the amounts present in consumer products by atleast 95% by 2015.
However, several environmental groups including EWG feel this voluntary pact is insufficient. This pact does not apply to Chinese companies, for example, which are among the leading manufacturers of food packaging.
Also, despite agreeing to phase out PFOA, several of the companies who have signed the pact, like DuPont, continue to maintain that PFOA is safe and does not pose any health risk to the general public.
As a part of their move to replace PFOA, the industry is lobbying to use C6 or Perfluorohexanoic acid (PFHA). This contains 6 carbon atoms to PFOA’s 8 carbon atoms.
Unfortunately, C6 also has several health and environmental concerns:
Like its predecessor PFOA, C6 is a very persistent chemical in the environment. It is potentially much more toxic to marine organisms than PFOA, and like PFOA, crosses the placenta to contaminate children before birth, according to an EWG study of umbilical cord blood.
The limited number of studies on C6 is in itself a cause for concern – PFOA because of its long history of use, has had a lot of independent and industry funded studies. But C6 in comparison is a newbie – very little scientific data exists on its safety and whatever exists points to potential alarm bells.
Who makes PFOA and where can I find it around my home?
Worldwide, DuPont, Clariant, Asahi and Daikin are the big manufacturers of PFOA.
In your home, PFOA can be found as an enabler to create non stick cookware. Apart from this, it could also be found in the following products:
1. Microwave popcorn bags
2. Frozen pizza boxes
3. Gore-tex clothing
4. Packaging for French fries in popular fast food chains
5. Any other food packaging with a coating that repeals oil and water
3. PFOS – Per flouro octanesulfonic acid
Per flourooctanesulfonic acid was produced by 3M in 1949. It was a key ingredient in Scotchgard a patented stain repellent produced by 3M and other stain repellent products.
PFOS, its salts and its precursors were used historically to repeal water, oil, soil, and grease for carpets, fabrics and upholster. Additionally they have also been used in food packaging and as surfactants in specialised applications like fire fighting foam, aviation hydraulic fluids and fume suppressants for metal plating.
Apart from this, derivatives of PFOA and PFOS are also used as inert substances in pesticides – inerts can sometime form upto 99% of a pesticide product! As per US EPA guidelines, inerts are not required to be public information on the pesticide package, so most consumers would be unaware that their already toxic pesticide contains even more lethal substances.
PFOS is characterised by very widespread prolific use, and is little understood in terms of its pathways into sentient beings.
PFOS threat to human health and wild life
PFOS is now widely seen across wildlife, being resistant to environmental breakdown, and is found right from polar bears in the arctic to dolphins in Florida, and seals and otters in Canada. Traditional scans did not detect PFOS earlier, because unlike other POPs (persistent organic pollutants); PFOS binds to protein in the body and not to fat.
PFOS is a persistent, bio accumulative global pollutant that is toxic to mammalian species. In addition to its industrial production, PFOS can also accumulate from the degradation of its chemical precursors in the environment.
There are species related differences in how long PFOS persists in animal and human bodies – its half life in rats is 100 days, whereas its estimated half life in human beings is 4 years. Repeated exposure results in hepatoxicity and mortality across animals especially in infants and children within the womb.
PFOS is persistent in the environment and has been known to bio-accumulate in fish. It is acutely toxic to honey bees.
PFOS levels in pregnant women have been associated with preeclampsia. It has also been associated with altered thyroid hormone values, an increased risk of high cholesterol and an increased risk of ADHs among early teens.
Regulatory status of PFOS
The Stockholm Convention on persistent organic pollutants (POP) in 2009 included PFOS in Annex B which is a schedule that asks for restricted use on the chemical. It is worth noting that PFOS joins DDT in this list suggesting restricted use!
Who manufactures PFOS and where can I find it in India
Used as the key ingredient in Scotchgard, created by 3M, PFOS has been around for 40 years or more. In 2000, 3M announced they would eliminate their line of PFOS based products in 2002 citing precautionary concerns due to the chemicals widespread absorption by human and animal life and its bio accumulative properties. 3M however disclaimed any health threats form the chemical citing over 700 studies that established the chemical’s safety.
But, with any such confident claim, lurks the spectre of unshared information, as did here as well. The U.S. EPA’s assessment of 3M ‘s own documents shared a different story.
PFOS was found to cause postnatal deaths in the offspring of a 3M run study PFOS on rats in the second generation. Monkeys exposed to PFOS were found to exhibit loss of appetite, excessive salivation, laboured breathing, depressed activity levels, among other symptoms.
After the Stockholm convention PFOS was labelled as a restricted use POP and put into annex B with 2 types of uses – acceptable uses for which no phasing out was necessary, and restricted uses which were supposed to be phased out in 5 years or less.
Among its acceptable uses, PFOS has been agreed to be used indefinitely in photo imaging, coatings for semi conductors, aviation hydraulic fluids, metal plating, medical devices and fire fighting foam.
Among its permitted restricted use, In India, PFOS has been allowed either directly or as an intermediate in the production of chemicals for the following uses:
2. Leather and apparel
3. Textiles and upholstery
4. Paper and packaging
5. Coatings and coating additives
6. Rubber and Plastics
In short, in India, PFOS will be present either directly or as an intermediary in every single one of its applications so consumers of these products are directly at risk.
The first step towards a healthy home – the home audit
Please start by doing a home audit to identify products in your home that contain PTFE, PFOA, and PFOS, and make a list.
A home audit is especially useful when you want to make a dramatic behaviour change : I’ve used it quite successfully to purge my kitchen of plastics, and to start my recycling bin.
The home audit almost always points out behavioral excesses: too much take away food leading to loads of un-recyclable plastic containers, for example, or an excessive dependence on non-stick dishes leading to a dangerous level of PTFE at home.
Keep this list in hand and wait for part 3 of the series, where I will discuss alternatives to the nasty Ps and how you can create the ideal healthy, eco kitchen.
Until next time, watch out for the nasty Ps and happy auditing and purging!