Silicone is viewed as one of the best alternatives to plastic. Many consider it to be a breath of fresh air in a world polluted with plastic.
Silicone is often used for different food applications like food storage, baking, and cooking due to its superior elasticity and temperature resistance.
However, is silicone so benign, or is there more to it?
Is silicone safe for food storage? Silicone is generally considered safe for food storage. However, conflicting data shows that silicon may not be fully inert, and it can release varying, usually, low levels of toxic chemicals into the food. Higher levels of chemicals may be released with fatty and greasy food or when the silicon container is subjected to high heat.
With all that being said, during my research, I found a lot of different information about this somewhat controversial topic. If you are interested, you will find more details below.
What Is Silicone?
Silicone is a human-made synthetic polymer. It is made from silicon, oxygen, and other elements like hydrogen and carbon.
There is a difference between silicone and silicon. Silicone is the polymer material which is made from silicon. And silicon (without the “e”) is a chemical element that is created by heating carbon with silica.
Silicone is being used for the making of a wide number of different things like cookware, bakeware, kid’s toys, trays, food containers, lid gaskets, pacifiers, utensils, and so much more.
One of its downsides is that it is not biodegradable, and even though it can technically be recycled, not a lot of recycling facilities accept silicone products.
Also, it is hard to say how environmentally-friendly silicone is. Silicone is not exactly zero-waste material either. You may have noticed that silicon is comprised of all-natural products. But to be turned into silicone it requires hydrocarbons which are a byproduct of petrol.
With all that being said, seeing how silicone will be in almost constant contact with either our body, food, or the beverages and water we drink – this begs the question, is it safe?
Is Silicone Toxic?
Silicone is generally considered safe for food storage. In fact, the Government of Canada has stated that silicone does not react with the different foods or beverages and that the use of silicone as cookware is not associated with any health hazards.
And back in 1979, the U.S. Food and Drug Administration stated that silicone is made from elements that are safe and suitable for food applications. But the production of silicone cookware did not truly begin until a decade later. And the first-ever silicone synthesis was achieved in 1940.
So one could question whether we even have had enough time to truly test, measure, and determine the effects of silicone on the human body.
Silicone may not be so benign after all, as there are some studies suggesting silicone may not be entirely harmless in certain conditions.
First, silicone can react with your food, and it can leach toxic chemicals into the food.
Testing was carried on silicone bakeware, and it was discovered that the silicone could leach siloxanes into the foods, including platinum, aluminum, magnesium, and calcium as well.
A second study also concluded that silicone was leaching off siloxane. Fat and greasy foods promoted the highest siloxane migration, while milk-based foods, the lowest. The total amount of siloxanes seemed to vary depending on how the silicone molds were tempered.
And another study found that silicone bakeware was, in fact, not completely inert at all temperatures. Some of the silicone molds were losing about 0.5% of their mass when subjected to heat for 4 hours.
A different study also concluded that small amounts of chemicals were released from silicone – about 0.44%. This percentage seemed to drop to 0.14% with silicone products that have been used for a while.
This study aimed to determine and look into 3 different cyclic siloxanes and 3 different linear siloxanes found in silicone. The migration was tested with three different foods, baby formula, milk, and simulant solution. After 6 hours, there were no detectable siloxanes in the baby formula or the milk. However, after 72 hours, there were some low detectable levels of siloxanes in the simulant solution.
It was found that the silicone tubing for medical applications can also leach off different chemicals.
A different study found took a look at 49 different silicone products. There were no detectable levels of siloxanes in the 8 samples of coated paper; however, in the other 41 silicone product samples, varying amounts of siloxanes were found. After a valuation of the potential levels of migration, it was concluded that the amount of siloxanes that would leach into the food should not be exceeding the safety regulations.
That all goes to show how difficult it is to pinpoint whether or not silicone is dangerous. The problem may not even be with silicone itself but with the other chemical additives that manufacturers may use.
So is silicone toxic? Silicone is widely considered to be relatively safe. However, there is data showing that it may not be completely inert as frequently claimed. The amount of chemicals that will leach off from silicone products can vary from negligible to high. So extra caution should be exercised.
Are Siloxanes Found in Silicone Toxic?
There are different types of siloxanes. Some of the more commonly found in silicone products are the D3, D4, D5, and D6.
D4 and D5, are a tricky subject, as there is some conflicting data online.
D6, on the other hand, is also of concern as it can accumulate in aquatic organisms, and it is considered toxic. However, D3, D4, D5 also may have the potential to accumulate and may potentially be dangerous.
Additionally, the European Union recognizes some siloxanes as potential endocrine disruptors.
Are Silicone Gaskets in Water Bottles Safe?
The sealing gaskets found in bottle caps are frequently made from silicone.
Given the smaller form and the lack of heat exposure, silicone gaskets may be considered relatively safe. A high-quality silicone gasket should not leach any significant amounts of chemicals. However, make sure not to subject it to high temperatures.
Are Silicone Cookware and Bakeware Safe?
Considering all the information above, I would prefer to err on the side of caution.
Silicon cookware and bakeware may not be entirely safe as it has been shown that it can leach a number of different harmful and toxic chemicals into the food – especially greasy food. Thus despite the claims, silicone should not be used for hot applications—especially low-quality silicone, which may contain different fillers and additives.
Is Silicone Dangerous at High Temperatures?
Do not expose silicone to temperatures above 392°F ( 200°C ). Exposing silicone to such temperatures can be extremely dangerous for one simple reason. If you expose plastic to such temperatures, it will melt. However, silicone does not melt – when it reaches a high enough temperature (typically about 842°F or 450°C), it will combust.
Is Silicone Safer Than Plastic for Food Storage?
An important question that is not easily answered.
Plastic has been proven to be harmful to human health. Plastic leaches toxic chemicals like BPA and phthalate, which can disrupt the way our body works. Even BPA-free plastic is not considered to be entirely safe.
Great Silicone Container Choice to consider:
- SET OF 4 SILICONE FOOD STORAGE CONTAINERS - Perfect silicone tupperware set for lunch boxes, leftovers, take out or as meal prep container. Each...
Last update on 2021-06-20 at 01:47 / Affiliate links / Images from Amazon Product Advertising API
On the other hand, silicone, although there is some evidence it can leach harmful substances like the siloxanes, compared to plastic, it seems like a safer bet. With all that being said, it is worth noting that silicone products are usually BPA, BPS, and phthalate-free. This is a step in the right direction. However, it is hard to say if the potential migration of siloxanes offsets this advantage.
Overall, silicone is also more durable, more inert, and with better heat resistance compared to plastic.
However, it is worth noting that we are yet to discover the full implications of using silicone, the data is simply lacking, and it is hard for anyone to make the right judgment call.
What Is the Difference Between Food Grade Silicone and Medical Grade Silicone?
One of the problems with food-grade silicone is that with time it tends to degrade and break down.
Medical grade silicone, which is also known as platinum silicone, is of better quality compared to food-grade silicone. Platinum silicone has improved heat resistance too – it can withstand temperatures from -60ºC to 220ºC (-76ºF to 428ºF) – and enhanced durability and longevity.
It is better, although more expensive, alternative for pacifiers, bottle nipples, and food storage containers.
How to Choose a Safe Silicone Food Storage Container?
With all that being said, there are a few things you can do if you really need to use a silicone-based container for storing food.
- Make sure that the container does not contain any BPAs, including the coloring agents used on it;
- Check if the silicone is 100% food grade;
- Make sure the silicone does not have any chemical fillers or additives. You can try testing it by bending or twisting the surface of the silicone container. If white material shows through, then fillers may have been used – 100% pure silicone typically does not change its color.
- Make sure that appropriate testing for metal contamination has been done (for example, is it lead-free?);
Are There Any Alternatives to Silicone for Food Storage?
Judging by the information we have for now, and depending on how you use them, silicone storage containers may be a relatively safe option. Silicone may be safe for cold applications; for storing food in the fridge, freezer, and at room temperatures.
As previously noted, exposing silicone storage containers to high heat should be avoided to the best of one’s abilities.
If you are concerned about the potential health hazards that come from silicone, there are a few safer alternatives.
Plastic food storage containers are also a no-go because they have also been proven to leach harmful chemicals into the food.
In this case, it is best to go for food storage containers made from borosilicate glass, ceramics, or food-grade stainless steel. All three of these are safe food-grade materials, especially glass, which is inert and does not contain any harmful chemicals or toxins.
Some Storage Containers I found on the market:
Last update on 2021-06-20 at 04:47 / Affiliate links / Images from Amazon Product Advertising API
Silicone storage bags are handy for storing small portions of food. Since we are not going to be exposing them to high temperatures, these may be relatively safe.
The problem comes from the fact that if you start looking for an alternative to them, things may not seem very promising. Frequently you will stumble upon either silicone or plastic bags.
So far, the only comparable and better alternatives are beeswax wrap bags. They are made from cotton, which has been exposed to beeswax. Both are natural materials. Keep in mind though that some bags may be made from a different type of wax, like paraffin wax or soy wax, which are not as natural and beeswax. However, if you are in a pinch, even parchment paper can be used for food storage.
Beeswax wrap bags are better at keeping your food fresh, tasty, and they have natural antibacterial properties. However, they are suitable for short term storage, refrigerating, and freezing.
For long-term storage (for 1 year and longer), a safer alternative is to use Mylar bags, which, if properly used, can keep your dry food fresh and tasty for up to 30 to 40 years.
Storage Covers and Lids
Another very tricky subject but one where beeswax may come in handy again. If you have food stored in a bowl or any type of container that does not have a lid, you can use beeswax wrap to cover it.
Alternatively, it is better always to buy food storage containers that have lids.
Go for metal food containers, ceramic, or glass food containers. Not all of these will be 100% free from plastic or silicone, so make sure to take a good look at the description of the product. In any case, even if the lids do contain some silicone gaskets, the exposure will be minimal.
There is a wide variety of silicone food storage trays starting from ice cube trays, baby food trays, hot dog trays, ice cream trays, and so much more.
The good news is that there are usually safer alternatives made from stainless steel – there are even stainless steel ice cube trays!