Is it Safe to Pour Hot Coffee into Plastic Cups? (Safe Types & Alternatives)

Last Updated on June 26, 2023 by Barry Gray

Like many of us, I love going out for a scenic drive occasionally, and I will always take a cup of coffee with me for the ride. I used to use an old travel mug that had seen better days.

When the whole ‘BPA is dangerous in plastics’ headline hit the news, I hit a panic. Plastic was not such a good idea anymore.

I heaved a sigh of relief when I noticed an inner casing inside my mug.

You should not put hot coffee in any plastic bottle. BPA is an issue, and the heat can break down the BPA leading to chemicals seeping into your coffee. It has been linked to various health issues, but there are alternatives out there that are safe for you to use.

I’ve done a deep dive into the problems of BPA and other chemicals to save you time. BPA’s can be bad news used over time. Plastics and hot coffee can cause leaching. Here’s what I found.

plastic cup drinking coffee

What are the Dangers of Plastic?

It’s no surprise that plastic is made from various chemicals, many of which can harm human health. Just through heating, the plastic can leach chemicals into your coffee. 

It’s really not a pleasant thought at all. 

One of the more prominent chemicals used is bisphenol A or (BPA). BPA has been linked to many health issues, including reproductive health, cancer, and even heart disease. 

The mere thought of it can send shudders down my spine. These studies are still active right now. 

However, I don’t want to be taking any chances, and the main studies I discovered included:

  • A 2022 study published in the journal “Environmental Health Perspectives” found that exposure to BPA during pregnancy was associated with an increased risk of preterm birth.
  • A 2021 study published in the journal “Nature Medicine” found that BPA exposure could disrupt the gut microbiome, leading to several health problems, including obesity and diabetes.
  • A 2020 study published in the journal “Environmental Research” found that BPA exposure could increase the risk of heart disease.
  • A 2019 “Toxicological Sciences” study found that BPA exposure could increase cancer risk.

These are just a few recent studies conducted on BPA and human health. After googling for results, there were so many I decided to find out which plastics were safe for my coffee hit on the run. 

To cut to the chase and save you time, I have minimized the results and have found these tips can help you avoid the dangers of plastic. 

  • Avoiding plastic food containers and bottles.
  • Using glass or stainless steel containers instead of plastic.
  • Washing plastic containers thoroughly before using them.
  • Avoiding microwaving plastic containers.
  • Choosing BPA-free plastics when possible.

The Issues with Plastic and Hot Water

hot water into plastic cup

The heat of hot coffee can also cause the plastic to melt or deform, even on a molecular level.

This can release even more harmful chemicals into the coffee and make the cup more likely to leak. In addition, the heat can also alter the taste of the coffee, making it bitter or metallic. 

Or, in my words, like plastic and water mixed. 

None of that creates a pleasant thought in my mind. I’m sure most people reading this will now feel the same way.

The Effect on Taste

The taste of coffee can also be affected by the type of plastic from which the cup is made. 

Some plastics, such as polystyrene, can impart a bitter or plasticky taste to the coffee. Other plastics, such as polypropylene, are less likely to affect the taste of the coffee.

I admit that the difference may only be slight, and you may not even notice it. However, do you really want to take that risk?

What is a Good Plastic Cup Solution for Travelers?

If you are a traveler like me, who needs to take coffee on the go, there are several safer alternatives to plastic cups. 

Stainless steel travel mugs are a good option, as they are durable, do not leach chemicals, and will not melt. 

Glass travel mugs are also a good option. Still, they are more fragile than stainless steel mugs.

I will talk more about that later on. In the meantime, BPA is not the only concern regarding plastic cups. 

Here is another list of chemicals you need to be aware of when it comes to storing coffee while on the move.

Types of Plastic to Avoid

The following types of plastic should be avoided when drinking hot coffee:

  • Polystyrene (PS)
  • Polyvinyl chloride (PVC)
  • Styrene is a chemical used to make polystyrene, a type of plastic often used for coffee cups. Styrene can also leach into food or beverages when heated. This can cause a bitter or metallic taste in the coffee and may also harm health.
  • Other chemicals leaching from plastic cups include phthalates, heavy metals, and flame retardants. These chemicals can also have adverse health effects.

The risk of chemical leaching from plastic cups is increased when the cups are heated. Which includes pouring hot coffee into the cup. 

So if you are in the garden, for example, and using a travel mug just because it is easier to handle, don’t rewarm your coffee in this mug in the microwave

This is because the heat can cause the plastic to break down and release the chemicals. The risk of chemical leaching increases if the cups are scratched or damaged.

The Wrong Plastic Mug Can Spoil The Taste of Coffee 

In addition to the health risks, as if that is not enough, plastic cups can also alter the taste of coffee. 

Some plastics, such as polystyrene, can impart a bitter or plasticky taste to the coffee. This is because the plastic can react with the coffee’s acidity.

I hate the idea of anything having the ability to change the taste of my coffee, so here are a few tips I’ve come across that should stop this happening. Or, at least lower the chances of it doing anything to your fresh brew.

  • Choose a BPA-free plastic cup. Hunt around for approved coffee cups that are BPA-free. In fact, choose BPA-free for all of your plastic products. If you want to be more environmentally savvy, you can use a reusable glass inner for years to come. 
  • Avoid using scratched or damaged plastic cups. Scratches or damage in the plastic can allow chemicals to leach into your coffee. Cheaper cups degrade over time, so keep an eye on the health of your travel cup. Spending more money in the short term might pay more for a longer-term benefit. 
  • Do not heat the plastic cup in the microwave. Microwaving plastic can cause it to break down and release chemicals. 
  • Wash the plastic cup thoroughly after each use. This will help remove any residual chemicals or flavors left behind. I noticed a massive difference when I washed my cup in the dishwasher instead of the sloppy rinse in the sink. If you don’t have a dishwasher for some reason, use a good cloth soaked in mild soap and wash the cup, rinsing well. 
  • Let the coffee cool slightly before pouring it into the plastic cup. This will help reduce the amount of heat transferred to the plastic, which can reduce the risk of chemical leaching.

How to Stop Chemicals Leaching Into Your Coffee

I’ve mentioned the issue of chemicals leaching into coffee, so is there anything you can do to stop that happening? Actually, there are a few ideas I need to share with you regarding this.

  • Use a double-walled plastic cup. Double-walled cups help to insulate the coffee, which can help to prevent the plastic from getting too hot and leaching chemicals. These are then lined with stainless steel. 
  • Choose a cup made from food-grade plastic, such as polypropylene or stainless steel. These plastics are less likely to leach chemicals than other types of plastic.
  • If you are concerned about the taste of your coffee, consider using a paper cup instead of a plastic cup. Paper cups are less durable than plastic cups, but they are less likely to alter the taste of your coffee.

My Safer Travel Mug Options 

I understand that some people may be a bit stressed as to the coffee mugs they can now use. So, as I’m responsible for making you anxious, here are a few of my suggestions for a safer travel mug.

  • Klean Kanteen Classic Insulated Travel Mug: This mug is made from double-walled stainless steel and is BPA-free. It is also vacuum insulated, which helps keep your drinks hot or cold for hours. 
  • S’well: This mug is also made from stainless steel and is BPA-free. It is designed to be slim and lightweight, making it easy to carry. 
  • Hydro Flask Flex Sip Coffee Mug: This mug is made from stainless steel and is BPA-free. It has a leak-proof lid and a comfortable grip. It also comes with various lid options, so you can choose the best option. 
  • Yeti Rambler: This mug is made from stainless steel and is BPA-free. It is known for its durability and ability to keep drinks hot or cold for hours. 
  • Zojirushi Stainless Steel Travel Mug: Made from stainless steel and is BPA-free. It has vacuum insulation that helps to keep drinks hot or cold for hours. It also has a wide mouth opening, making it easy to clean and drink. I wouldn’t say I like those mugs that make you dribble. 
  • KeepCup: This mug is made from borosilicate glass and is BPA-free. It is also dishwasher-safe and recyclable. KeepCup mugs come in a variety of sizes and colors.
  • Frank Green: This mug is made from recycled stainless steel and is BPA-free. It has a leak-proof lid and a bamboo sleeve, making it both sustainable and trendy. 
  • Ecoffee Cup: This mug is made from bamboo fiber and is BPA-free. It is also 100% compostable, making it an excellent environmental choice. Ecoffee Cup mugs come in a variety of sizes and colors.

These are just a few of the many BPA and chemical-free travel mugs available on the market. When choosing a travel mug, it is crucial to consider your needs and preferences. 

My Recap on Putting Coffee in Plastic Cups

This is a scarier subject than I realized, so here are just a few key points that I feel are the most important regarding using plastic cups for coffee.

  • Look for cups that are made from BPA-free plastic.
  • Choose cups made from food-grade plastic, such as polypropylene or stainless steel.
  • Avoid scratched or damaged cups, as this can increase the risk of chemical leaching.
  • Do not heat the cup in the microwave.
  • Wash the cup thoroughly after each use.

Honestly, it doesn’t sound like much, but it could help your health, so I would advise it’s best to pay attention to the tips.

My Conclusion

I care about my health and am nervous when faced with the possibility of being exposed to chemicals.  For that reason, I’m careful about what I put my coffee in when it’s all nice and hot.

Plastic cups are not a no-go area, but it does involve taking care over what you use. I hope the tips mentioned above can help.