Microplastics in bottled water: what we know

Bottled water can contain very large numbers of tiny plastic particles, most of them nanoplastics too small to see with a normal microscope. Tap water in a steel or glass bottle is the simplest swap, and it costs a fraction of a penny per litre.

What the research found

A 2024 study used a new laser imaging method to count individual nanoplastic particles in bottled water. The researchers found hundreds of thousands of particles per litre on average, around nine in ten of them nanoplastics. Earlier methods missed most of these because they were too small to detect.

Where the particles come from

Likely sources include the bottle and cap themselves, the filters used during purification, and the bottling process. Squeezing bottles, heat and repeated opening may add more.

Is tap water better?

UK tap water is tightly regulated. In England and Wales, the Drinking Water Inspectorate checks that suppliers meet strict standards. Tap water isn't guaranteed plastic-free, but it avoids the bottle entirely and cuts a large amount of plastic waste.

What to do

• Drink tap water, from a glass at home or a stainless steel bottle when out.
• If you dislike the taste, chill it in a glass jug.
• Choose a bottle with a steel lid if you want nothing plastic touching your water.

See the full swap: bottled water → tap water.