What “microplastic-free” means on a home care label

The European one is the most worked out, and it does not use the word. Under entry 78 of Annex XVII to REACH, introduced by Commission Regulation (EU) 2023/2055, the regulated substance is a synthetic polymer microparticle 1. A polymer qualifies only if it is solid, carbon-containing, synthetic or a chemically modified natural polymer, not degradable under Appendix 15 and not soluble above 2 grams per litre under Appendix 16 2. It must then sit in particles at 1 per cent by weight or more, or coat them continuously, with at least 1 per cent by weight of those particles measuring 5 mm or less in every dimension, or 15 mm or less in length where the length to diameter ratio exceeds 3 2.

California wrote a shorter one and left the exclusions out. Its State Water Board adopted a definition of microplastics in drinking water on 16/06/2020, under Resolution 2020-0021: solid polymeric materials to which chemical additives or other substances may have been added, being particles with at least three dimensions greater than 1 nm and less than 5,000 micrometres 3. The only exclusion covers polymers derived in nature and not chemically modified other than by hydrolysis 3. There is no solubility carve-out, which is the most consequential difference between the two texts.

England went shorter still. The Environmental Protection (Microbeads) (England) Regulations 2017 define a microbead as any water-insoluble solid plastic particle of 5 mm or less in any dimension, and prohibit using microbeads in the manufacture of rinse-off personal care products and supplying such products 4. The words water-insoluble do the European solubility threshold’s work in a fraction of the space.

All three agree on a 5 mm ceiling and on solidity. They disagree on whether a polymer that dissolves counts, and on what they govern: chemicals in mixtures, drinking water, and rinse-off cosmetics. None of them tells a manufacturer what may be printed on a washing-up liquid.

Commission Regulation (EU) 2023/2055 was adopted on 25/09/2023 and entry 78 has applied since 17/10/2023 1. It prohibits placing synthetic polymer microparticles on the market on their own, or in mixtures where they are present to confer a sought-after characteristic at 0.01 per cent by weight or more 2. That is the architecture: a definition, a threshold, derogations, and a queue of deadlines by product type.

The deadlines matter more than the headline. Microbeads used as an abrasive were caught at once; everything else got a transitional period, and this shelf’s runs five years.

So a detergent sold in the EU today may lawfully contain a synthetic polymer microparticle and say nothing about it, until 17/10/2028 2. A pack claiming to be microplastic-free in 2026 is claiming something the law does not yet ask of anyone in that aisle: the strongest reason to take the claim seriously, and the strongest reason to check it.

Two exclusions do most of the work here. Only solid polymers are in scope, so liquid polymers fall outside entry 78, as does a liquid product holding solid polymers dissolved in it 2 6. Any polymer soluble above 2 grams per litre under Appendix 16 is excluded by the definition itself 6.

That settles the question everyone actually asks. The European Commission’s own guide puts it in a line: synthetic polymers meeting the Appendix 16 solubility criteria, polyvinyl alcohol given as the example, sit outside the restriction 6. A dissolving laundry sheet or tablet film can be sold in Europe after 2028 without touching entry 78, and its maker can say accurately that it holds no microplastic as the EU defines one.

That is a statement about a legal boundary, not about a drain. Whether polyvinyl alcohol breaks down in a working wastewater plant is a separate argument with published positions on both sides, and where Brussels drew its line does not settle it. The Californian definition, carrying no solubility exclusion, sits elsewhere 3. A microplastic-free claim on a detergent is therefore true or false depending on which document is in play, and the pack almost never says which.

The restriction is about intentional addition. It bites on synthetic polymer microparticles placed on the market alone or in mixtures, and articles under REACH sit outside its scope 6. A sponge, a brush and a cloth are articles, so entry 78 says nothing about what they shed in use. That is a hole in the middle of the phrase as a shopper understands it.

There is at least one published measurement of that hole. Su and colleagues, in Environmental Science and Technology in 2024, abraded melamine cleaning sponges and found poly(melamine-formaldehyde) fibres 10 to 405 micrometres long, formed by fracture of the struts inside the foam, at 6.5 million fibres per gram of sponge worn away 7. It is an abrasion rig rather than a kitchen sink, the figure is per gram of wear rather than per wash, and the paper’s global total is modelled from sales data. It is still the clearest number on a cleaning tool, and it describes shedding, which no microplastic rule reaches.

For nylon bristles there is less. We looked for a published measurement of what a nylon dish brush sheds in normal use and found none on 21/08/2026. A brush carrying the claim is usually describing what it is made of rather than what comes off it, and those are not the same fact.

On a bar of soap or a bottled cleaner, microplastic-free is a formulation claim: no ingredient in the mixture is a synthetic polymer microparticle under whichever definition is in play, checkable against an ingredient list where one is published. On a brush, sponge or cloth it is a materials claim about an article: the thing is not made of a plastic that can break into pieces, checkable only if the brand names the material.

A loofah sponge sold as 100 per cent microplastic-free, with its construction given as natural loofah, plant-based cellulose and cotton stitching, backs the materials claim with a material list 8. A synthetic sponge could say accurately that it contains no intentionally added microplastic while shedding fibres throughout its life. The phrase does not separate those two products, so the reader has to.

Not directly. No federal definition of microplastic governs a cleaning product label. The one federal statute in the area, the Microbead-Free Waters Act of 2015, bars manufacturing or introducing into interstate commerce a rinse-off cosmetic containing intentionally added plastic microbeads, and defines a plastic microbead as a solid plastic particle under 5 mm intended to exfoliate or cleanse the body 9. A dishwasher tablet is not a rinse-off cosmetic, and California’s definition governs drinking water testing rather than marketing 3.

What applies instead is the general law of deceptive advertising and the Federal Trade Commission’s Green Guides at 16 CFR part 260. Their status is worth stating plainly: they set out the Commission’s current views, confer no rights and bind nobody, and in an enforcement action the Commission must still prove the practice unfair or deceptive under Section 5 of the FTC Act 10.

Two sections bear on the phrase. Section 260.9 governs free-of claims: it is deceptive to misrepresent that a product is free of a substance, and a claim may deceive even where literally true, either because a substitute poses the same or similar environmental risks or because the substance was never associated with the product category 12. Section 260.4 says an unqualified general environmental benefit claim conveys far-reaching benefits a marketer cannot substantiate, and should be qualified with the specific benefit asserted 11. A microplastic-free line that names its polymer and its standard sits comfortably against both. One that floats free above a pack does not.

1. Decide whether you are holding a mixture or an article. A liquid, powder, tablet or bar should carry an ingredient list. A sponge, brush or cloth will not, so look for a material list instead.
2. On a mixture, read the list for polymer names: acrylates copolymer, polyquaternium, polyethylene, polypropylene, polyurethane and polyvinyl alcohol are the ones home care throws up.
3. Ask which definition the claim uses. A pack naming a standard, a regulation or a certification can be checked; one naming nothing is stating an intention.
4. Watch the solubility gap. A brand can be accurate that its product holds no synthetic polymer microparticle under EU rules and still send a dissolving synthetic polymer down the drain 6.
5. Separate what a thing is made of from what it sheds, and read silence about bristle or foam polymer as an absent answer rather than a reassuring one.
6. On an EU pack, remember the clock: nothing in the detergent aisle need comply until 17/10/2028, so the claim is voluntary and the burden of proof sits with the brand 2.

Settled: the EU definition and its thresholds, the exclusions for liquid, soluble, natural and degradable polymers, the deadlines, the exemption of articles, the Californian and English definitions, and the absence of any US rule for this aisle. All of it sits in documents anyone can open, cited below.

Argued over: whether the solubility exclusion sits in the right place, whether polyvinyl alcohol behaves in a wastewater plant the way that exclusion assumes, how much of a household’s microplastic load comes from cleaning tools rather than textiles and tyres, and whether a 5 mm ceiling with no agreed floor is a useful boundary. None of that is settled here. What this site compares is narrower and duller: whether a brand names its polymers, and whether the page says what the product is made of.