Metal
Stainless steel
Stainless steel is an alloy of iron, chromium and usually nickel. It isn't plastic, it lasts for decades and it's fully recyclable, which makes it the backbone of most plastic-free swaps. New pans can release small amounts of nickel and chromium into acidic food.
By PlasticFreeHome Research Team · Not yet reviewed by an editor · Updated 21 October 2026
- Also called
- 18/8 steel, 18/10 steel, 304 steel, 316 steel, inox
- Type
- Metal
- Found in
- water bottles and flasks, pans and kettles, lunchboxes and food tubs, cutlery and children's plates, safety razors, straws
- Heat
- Excellent heat resistance. New pans release the most metal, especially with long-simmered acidic food.
- Recycling in the UK
- Fully recyclable. Take old pans and cutlery to the scrap metal skip at your local tip.
What it is
Stainless steel is iron alloyed with at least 10.5% chromium, which forms an invisible protective layer that stops it rusting. Most kitchen steel also contains nickel. You'll often see the mix written on the product:
- 18/8 and 18/10 mean about 18% chromium and 8% or 10% nickel. Grade 304 is the common food-grade steel.
- 316 adds molybdenum for better corrosion resistance, often used in premium bottles.
- Nickel-free steels (sometimes "18/0", or grade 430) are less corrosion-resistant but avoid nickel.
It isn't plastic, it doesn't shed microplastics, and it lasts for decades. That's why it's behind so many swaps: plastic kettle → steel, non-stick pan → steel, plastic lunchbox → steel, kids' tableware → steel and bottled water → tap.
Does steel release anything?
A little, in some conditions. A 2013 study cooked tomato sauce in stainless steel for hours at a time. Nickel and chromium in the sauce rose, the most with brand-new steel, long cooking and some steel grades. The release fell over the first several uses and then levelled off, but didn't disappear.
How much this matters depends on the person. It's most relevant for people with a nickel allergy: the study notes that nickel taken in by mouth can cause skin reactions such as dermatitis.
How to use it well
- Season new pans by using them a few times; release drops after the first several uses.
- Don't store acidic food, like tomato sauce or citrus, in steel for days.
- If you have a nickel allergy, consider nickel-free steel, cast iron, enamelled cast iron or glass for long-cooked acidic dishes.
- Check what touches the food: many "steel" bottles and lunchboxes have plastic or silicone lids and seals.
Recycling
Steel is infinitely recyclable. Cans go in your recycling bin; pans, cutlery and old bottles go in the scrap metal container at your local tip.
Related guides
Sources
Swaps involving stainless steel
Bottled water → tap water in a steel bottle
Bottled water carries hundreds of thousands of plastic particles per litre. UK tap water is cheap and safe.
Swap first · about 3.0 kg of plastic a year
Plastic and "bamboo" kids' tableware → stainless steel
"Bamboo" kids' tableware is usually melamine plastic. Steel is unbreakable and safe with hot food.
High priority · about 200 g of plastic a year
Plastic kettle → steel kettle with no plastic in the water
Boiling water in plastic several times a day is one of the most frequent heat-plus-plastic contacts in a home.
High priority · about 250 g of plastic a year
Non-stick pan → stainless steel or cast iron
Non-stick coatings are a fluoropolymer plastic that wears off over time. Steel and iron pans last decades.
Worth doing · about 30 g of plastic a year
Plastic lunch box → stainless steel
Steel lunch boxes last for years, go in the dishwasher and don't stain or crack.
Worth doing · about 100 g of plastic a year
Disposable razors → stainless steel safety razor
A safety razor lasts a lifetime and blades cost pennies. The learning curve is a week.
Lower priority · about 300 g of plastic a year