Although Plastic Is Everywhere In Our Homes, Our Lifestyles And Our Kitchen We Can Still Make Wise Choices About How We Use Plastic If We Know Its Properties.
This article gives you an overview of the properties of plastic in relation to how we typically use plastic in the kitchen.
Some of the properties you may already be familiar with, however, I do encourage you to read the whole article because the more you know about the properties of plastic the easier it is for you to decide how or when you choose to use it.
The first thing that is critical to know is that the process of plastic making, known as polymerisation, is rarely complete which means that a significant portion of the chemical components of the plastic are not secured in the polymeric structure of the plastic and are therefore free to migrate and leach out of the plastic.
The chemical components used in the manufacture of plastic are well known to be dangerous to our health.
“90% of the markets for the chemicals of greatest concern to human health is in polymer manufacturing to make
244 million metric tonnes of plastic” - Rossi & Blake (2014)
Some of the chemicals used in plastic have become very well known, such as Phthalates and Bisphenols. It is a very good
that awareness is rapidly increasing, however we must not forget that there are over 6000 dangerous chemicals used in the
manufacture of plastic and that they all leach from plastic because they are not chemically part of the polymeric structure.
Now that we know that plastic is not stable we need to know under what conditions the plastic
is most likely to leach its chemical constituents.
“The exact chemical composition of almost any commercially available plastic part is proprietary and not known.
A single part may consist of 5–30 chemicals, and a plastic item containing many parts (e.g., a baby bottle)
may consist of ≥ 100 chemicals, almost all of which can leach from the product, especially when stressed.” - Yang et al (2011)
1. EXPOSE PLASTIC TO SUNSHINE
It is well accepted that plastic is ‘stressed’ by sunlight, oxygen, heat and abrasion and that under these conditions the release of the non-polymerised chemical components of the plastic is accelerated.
If oxygen alone stresses plastic, it begs the question ‘how on earth could plastic ever be safe’?!
I don’t think it is. Do you?
UV light is considered to be the most ‘stressful’ to plastic and causes the plastic to release monomers such as (but not limited to) BPA that have detectable estrogenic activity and other chemical additives, such as phthalates, that are known to have negative effects on the endocrine system.
We take plastic out into the sunshine with us regularly; think of plastic water bottles, lunch boxes, soft drink in plastic bottles, plastic cutlery, melamine tableware, plastic water jugs, plastic cups/glasses/wine glasses and so on. Perhaps in some of these instances we should choose to replace the plastic with glass, stainless steel or timber.
2. HEAT PLASTIC IN THE MICROWAVE, OVEN, DISHWASHER, STEAMER, STERILISING EQUIPMENT OR BY PUTTING HOT FOOD INTO PLASTIC
“Because DEHP and DBP are not chemically bound to plastic matrices, they can easily migrate, due to thermal
or mechanic stress, into food contacting plastic surfaces and equipment such as containers, tubes, gloves,
and packaging, including adhesives and imprints. The available data show that retail-packaged foods are widely
contaminated by phthalate plasticizers...” - Cirillo et al (2011)
DEHP and DBP are well known phthalates, commonly used as plasticizers which are added to plastic to increase its flexibility. Heating plastics encourages the release phthalates which are considered to be reproductive and development toxicants for humans and animals.
Other than the obvious ways we could be heating plastic other places where you might be unnecessarily increasing your exposure is by using
Also beware of and avoid the phthalates that are often used in personal products such as lotions, perfumes and deodorants.
3. SCRATCH PLASTIC OR USE SCRATCHED PLASTIC BOTTLES OR CONTAINERS OR CHOPPING BOARDS
One kitchen appliance that is surprisingly harmful to plastic is the dishwasher. The food particles swished around in the water act as tiny abrasives (like sand blasting) in very hot conditions. Handwashing with a bottle brush or dish brush also damages plastic.
A plastic chopping board is obviously going to be scratched and they also contain added chemicals with ‘antimicrobial’ properties, these are commonly nanoparticles which are very hard for the body to isolate and eliminate.
“People exposed to higher levels of BPA due to use of plastic food and beverages containers are more likely to
develop cardiovascular diseases, diabetes and metabolic disorder.” - Srivastava & Godara (2014)
Plastics that have been scratched leach far greater amount of chemicals, up to 5 times more, including the range of Bisphenols (BPA, BPB, BPE, BPF and BPS).
4. KEEP FRESH VEGETABLES, LIQUIDS OR FOOD IN PLASTIC
“…diet is a significant source of exposure for toxic phthalates (DEHP and BBzP) and BPA. How and when phthalates
and BPA enter the food chain is not always clear, but the most likely source is plastic used in the manufacturing,
processing, storage, and transport of food. These chemicals can also be part of food packaging including plastic containers,
lids, can linings, dishware and utensils.” - Sathyanarayana et al (2013)
Although everyone is alert for the Bisphenol A (BPA) and the Phthalates, I would like to remind you of Formaldehyde. Formaldehyde is widely used in and known to leach from polyethylene terephthalate (PET) plastic bottles and melamine tableware.
In the case of bottles, for water and other drinks, the chemicals in the plastic leach into the drink in a ‘passive’ action and are dependent on how long the drink has been in the bottle, the temperature it was kept at and how much UV light it was exposed to.
In comparison to liquids such as water, fresh vegetables, are by nature still living, and therefore uptake the chemicals leached from the plastic in an ‘active’ way.
Fresh lettuce and spinach have been shown to take up measurable amounts of minerals in an experiment testing new biodegradable nanocomposite plastic made from clay and starch.
This experiment is interesting because it shows that vegetables do take up components from plastic, however, unfortunately the researchers chose not to test the vegetables for any chemical components of the plastic.
5. BUY FOOD THAT HAS BEEN IN PLASTIC FOR AN EXTENDED PERIOD OF TIME
The liquid in canned vegetables & soups has been shown to have detectable levels of BPA that has leached from the epoxy resin lining of the can.
“Consumption of 1 serving of canned soup daily over 5 days was associated with a more than 1000%
increase in urinary BPA” - Carwile et al (2011)
Although Bisphenol A (BPA) has become the most avoided Bisphenol, used as a monomer in polycarbonate plastics and epoxy resins, its most common replacement Bisphenol S (BPS) also leaches out of plastic and it also has estrogenic properties equal to BPA.
To avoid the chemicals
Now that you know a little more about plastic it is time to remind you that you can make a difference to your health by being more discerning about when and how you use plastic in the kitchen. There are many studies that show that BPA and Phthalates measured from urine samples change when the research participant’s diets are changed to increase or decrease their exposure.
It is worth using Fresh Produce Enhancer's for your vegetables and making the other changes listed below whenever possible because:
Unfortunately, it is unlikely these estrogenic migrating bio-accumulating chemicals will ever be fully tested or regulated as there are more than 6,000 different and highly toxic chemicals used in plastics that come into contact with food.
To keep yourself and your family safe:
You can make a difference for yourself, your family and our planet.
Plastic is absurdly hard to breakdown and all the chemicals that leach from plastic in landfill leach into our waterways. In fact, BPA is already being measured in waterways that supply urban centres and in the amniotic fluid of humans in developed counties.
Together we can make a difference. Start with a Fresh Produce Enhancer
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Carwile, J.L., Ye, X., Zhour, X., Calafat, A.M. and Michels, K.B. (2011) Canned Soup Consumption and Urinary Bisphenol A: A Randomized Crossover Trial, JAMA, vol 306 (20), 2218-2220.
Cirillo, T., Fasan, E., Castaldi, E., Montuori, P., Cocchieri, R.A. (2011) Children’s exposure to Di (2-ethylhexyl)phthalate and Dibutylphthalate plasticizers from school meals, Journal of Agricultural and Food Chemistry, vol 59, 10532-10538.
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Rossi, M.S. and Blake, A. (2014) The Plastics Scorecard: evaluating the chemical footprint of plastics, www.cleanproduction.org.
Sathyanarayana, S., Alcedo, G., Saelens, B.E., Zhou, C., Dills, R.L., Yu, J. and Lanphear, B. (2013) Unexpected results in a randomized dietary trial to reduce phthalate and bisphenol A exposures, Journal of Exposure Science and Environmental Epidemiology, vol 23, 378-384.
Srivastava, R.K and Godara, S. (2013) Use of polycarbonate plastic products and human health, International Journal of Basic & Clinical Pharmacology, vol 2 (1), 12-17.
Yang, C.Z., Yaniger, S.I., Jordan, V.C., Klein, D.J. and Bittner, G.D. (2011) Most plastic products release estrogenic chemicals: A potential health problem that can be solved, Environmental Health Perspectives, vol 119 (7), 989-996.
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