I used to feel DRAINED after hours of researching the answer to this question.
From how safe plastics are to use and if they are acid-free. But there are only a few handfuls of blogs that talk about plastic and its effects.
That’s part of why I’m sharing some of the lessons gathered from reading & researching different articles about this topic.
How to check if it is acid-free?
Avoid using poly boxes since they can keep acidity and do not shield your plastic from any of its harmful effects. Poly boxes come with two different symbols known to most consumers as PP and PE plastic.
However, poly boxes such as polypropylene (PP plastic) or polyethylene (PE plastic) have passed the Oddy test and are safe.
It means these plastics won’t produce any hazardous gasses or harm anyone. But you don’t want to put any acid inside the plastic storage boxes in the first place.
| Type | Recycling Numbers |
| Safe for Foods & Beverages | 1, 2, 4, and 5 |
| Avoid These Plastics | 3, 6, and 7 |
So if you plan to store food, you should only check for the recycling symbol containing numbers 1, 2, 4, and 5. You want to avoid numbers 3, 6, and 7 as they are incompatible with edible nutrients.
Advantages vs. Disadvantages of Poly Plastics
As we dive deep into the pros and cons of using poly plastic, we included a table below showing each advantage and disadvantage.
| Advantages (Pros) | Disadvantages (Cons) |
| *They won’t allow any water to come in.
*See-through quality *Keep rats out, and they won’t bite into the box. |
*Not best used for acid
*Large size plastic boxes are not always better |
Why are poly plastics changing the world?
Some of what makes poly plastic goods are that they are flood-prone, and no water will accidentally seep into the container and damage the goods inside.
Image 1.1 Examples of Poly Plastics
It makes it great for high tide or tsunami-prone areas as it would make any object placed inside to be safe from water.
Next, they control the moisture content inside the plastic container.
It means your food won’t gain or lose moisture during this stage. It explains how they are put in a temporary limbo state to prevent spoilage of anything inside and, at the same time, not lose any of their original water content if there is any present.
Most PP and PE plastics are usually transparent, allowing you to see through the contents inside the box without having to get it out of its moisture-limbo state. Unlike other packs where you need to open the lid to verify the contents, any polypropylene and polyethylene make it safe for food to be stored inside.
Another benefit of the suspended moisture-limbo is creating your own dehydration space.
You can create an environment where any objects placed inside will reduce their moisture content and eliminate any water levels.
Image 1.2 Suspended Moisture-Limbo State
This is ideal for situations that require you to dry things, such as placing a rusted metal inside the container to reduce all its moisture. You need to add a silica gel to the drying space.
One significant benefit of these plastic storage boxes is their anti-rat model. Any edible food placed inside won’t attract any rodent’s attention. It also helps in deterring any mosquitos in your food.
Lastly, they are usually much more affordable than document boxes in most corporate office settings. It depends on what size you are differentiating it, but plastic storage boxes generally offer much more advantages.
Extra Note: How Tall Are Plastic Storage Bins? (13 Facts for Beginners)
Why you should avoid using poly plastic storage boxes:
First of all, they don’t work well with acid. Like any plastic won’t be ideal with acidic content, don’t use this as a container for it.
You would also want to monitor the moisture-control level. One that is too high can lead to more risk.
Lastly, if you plan to use plastic storage boxes to conserve an artifact or any memento, avoid going for bigger plastic storage models, as they may contain unnecessary preservatives that are not aligned with prolonging the lifespan of your object.
Our Final Verdict: Should you buy one or not?
With all the benefits listed above, we can safely conclude that plastic storage boxes are comfortable to be used with food.
It might have some downside if you plan to preserve any artifacts. Still, it can reliably keep any deep waters away, making it safe to store any object and documents without worrying about the risk of flooding.
What type of plastic should you use instead?
The safest plastic is archival polyester. They usually have the recycling symbol with #1 located in the middle.
The plastic won’t show any signs of yellowing over time. This makes it ideal storage for anything object you want to be fully covered.
You can find most document storage boxes that use archival polyester material. They are used to make book jacket covers and can be found in different clothing apparel such as sleeves, shirts, etc.
Image 1.3 Archival plastic used to store historical pictures
They are great if you plan to preserve any priceless possession, such as a book, as most archival polyester plastics are seen on folders & page protectors.
It is built to not slowly degrade over time, an ideal choice for storing anything you want your grandson or granddaughter to see later on.
What Makes it Different: Safest plastic to use.
Breaking down each plastic number:
As a quick recap, numbers 1, 2, 4, and 5 are the only ones that are safe for storing food.
We already shared earlier how the number 1 is excellent for preserving artifacts. Next on the list are numbers 2 – 7,
Image 1.4 Different Types of Plastic Breakdown
#2 – HDPE Plastic
They are one of the top plastics commonly used on plastic bottles, toys, and other chemical containers such as shampoo and conditioner.
Image 1.5 HDPE Plastics are recyclable
Compared to other plastics, they can hold food and beverage well. They are also able to resist extreme UV temperatures and prevent any yellowing. You can see them also in shampoos and conditioners. They are also ideal for piping applications.
One crucial thing about HDPE plastic is it’s resistant to rust. You can see them in some structures, such as undergoing piping.
But it has some disadvantages, from being sensitive to stress cracking, which is a solid external cracking force.
They won’t break in everyday use, can’t also be composted, and have poor temperature capability.
They are one of the few recyclable plastics. HDPE plastic can save 50% of the material cost when reused. It not only saves you a few cents but will help protect the environment from plastic-burning waste.
What Makes it Different: Recyclable plastic
#3 – PVC Plastic
They are commonly known as PVC plastics. From the name alone, we can immediately guess why they are not safe to store any edible snacks.
PVC or polyvinyl plastic is present in many construction materials such as water pipes.
One primary reason they are dangerous to use is that they release harmful gasses when in use, which cause anything near them to dissipate over a couple of years slowly.
However, that same reason is why most people use them in the construction industry: they can build a solid resistance to wear and tear.
It also doesn’t allow for electricity to pass through. Their unique form will enable them to replace the traditional wood construction,
They can also be found in other objects like photo storage books and children’s toys.
If you ever look through the old photo albums and see some pages yellowing and are sticky to touch, it’s because of PVC. This is why PVC is not the standard plastic used to store items.
What Makes it Different: For construction use.
#4 – LDPE Plastic
Image 1.6 LDPE Plastic
They are one of the most flexible forms of plastic that you can arrange in various shapes and sizes. They won’t display the best transparency but an affordable choice of plastic.
You can see them usually in plastic bags and other plastic materials where it has no solid shape. Its fluidity allows it to resist any changes in its form. They are also able to withstand any water content from seeping inside.
They can also withstand extreme drops from high buildings as they have one of the industry’s most substantial durability. You can see them in water containers and pipes.
They are also present in water-plastic bottles where no matter how many times you accidentally throw them into the ground, the shape of the container won’t break nor change.
Poor electricity conductor makes it one of the most common choices for covering exposed wires and cables.
But LDPE plastics come with some downsides. Because of their ability to change shape with heat, it has low heat resistance.
Overall, they are one of the most commonly used plastics because of their low-priced cost while achieving mass benefits for the general population.
What Makes it Different: For plastic bag use.
#5 – PP Plastic
Image 1.7 PP Plastic
It is one of the few plastics with a durable, long-lasting quality but isn’t clear enough to see what is inside.
It can hold its ground against any chemical intrusion. Acids won’t react with PP plastic making it an ideal choice for medical ingredients such as cleaning formulas, fabric softener, detergent, and other chemical household solutions.
Unlike LDPE Plastic #4, they hold their shape for quite a while once they are flexed into shape. You can see them in use through bottle caps, packaging tapes, and straws. PP plastics can easily be reset back to their molding process by simply reheating the plastic again. Once cooled down, the plastic will hold its shape for a long time until exposed to extreme temperatures again.
It also comes with its fair share of disadvantages. For one, they are prone to UV disintegration.
This means that plastics could crack when exposed to extreme UV light. They are also prone to fire with their high flammability material.
Despite its disadvantages, people still use PP plastic because of its versatility.
What Makes it Different: Upgraded version of LDPE Plastic
#6 – Styrofoam
Image 1.8 Styrofoam
There have been numerous controversial cases about styrofoam on why it is not considered an “environment-friendly” plastic anymore. Despite this, styrofoam or polystyrene plastic is one of the few materials with insulation properties.
This makes it great to temporarily store foods and ensure that they stay warm until they are delivered to the buyer. One benefit is that styrofoam comes in various shapes and sizes to suit the amount of food needed.
They are also water-resistant and contain shock-absorption features to prevent damage from the material it is protecting.
It’s less expensive and easier to handle when it comes to the logistics & shipping process in comparison to standard plastic.
But it could also harm the environment. They are non-biodegradable and could last for years buried underneath the ground without any deterioration.
They are also made with non-renewable petroleum products making them harmful to the environment in the long run. Despite these disadvantages, they are still present in most Asian countries to serve as a temporary food container due to their affordable price.
What Makes it Different: Best for keeping the heat of food insulated.
#7 – Other Plastics
Image 1.9 Other Plastics
These are the “leftover” plastic that doesn’t match any of the previous six options. It includes hard plastic items like eyeglasses, CDs, and light bulb fixtures. They are also used in some hard plastic spoons and forks.
Another functionality is epoxy resins since this type of plastic is resistant to any damage and lightweight.
Its other name is Bisphenol A plastic or BPA. They are unsafe to come into contact with food since potential health risks could include cancer and possible reproductive disorder.
This is why requesting “BPA-free” food storage is essential.
What Makes it Different: Hard plastic
Section 7: Summary
To summarize, we have shared the different types of plastic, why numbers 1, 2, 4, and 5 are the only plastic safe for food storage, and why most poly plastic can’t handle the acid content except archival plastic.
Here are just some of the lessons about plastic that we have gathered from all across different sources to give you a one-stop-shop website with all the necessary information.
If you have any questions or feedback about this resource, feel free to send an email. We’d love to hear from you on how we can improve better as a blog.
