The formats

The scrub

Updated October 2026

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The legal half, settled quickly Then the physical half Salt and sugar behave differently Wet hands are the real contamination route Which argues for a wide mouth and a good lid And a jar sized to the fill Say where to keep it References

A scrub is a suspension that separates, in a jar opened with wet hands.

The legal half, settled quickly

Use an exfoliant that is not a plastic particle under five millimeters intended to exfoliate. Sugar, salt, ground shell, pumice, clay, coffee and jojoba esters are all ordinary and none of them is caught.

Then the physical half

A scrub is solid particles suspended in oil or an emulsion, and solids in a liquid settle. A customer opening a jar to find oil on top and grit at the bottom is seeing normal behavior, and saying so prevents the complaint.

Salt and sugar behave differently

Sugar dissolves readily in water and salt draws it, so a salt scrub picks up moisture and can harden while a sugar scrub can go syrupy. Same format, two different storage problems.

Wet hands are the real contamination route

A jar opened in a shower gets water introduced on every use, and an anhydrous oil-based scrub with water in it is a different product microbiologically. That is a preservation question for whoever formulates it.

Which argues for a wide mouth and a good lid

Wide so a hand can reach the bottom corner, and a lid that reseals after being handled wet. Of the 345 closures on this shelf, 301 are continuous thread and the liner is what makes the reseal real.

And a jar sized to the fill

A part-filled jar lets the contents move and separate further in transit. With 253 containers from 15 to 250 mL, matching the jar to the fill is achievable rather than aspirational.

Say where to keep it

Out of the direct spray, lid closed, used with a scoop if you supply one. It is specific advice that genuinely changes the product life, and customers follow specific advice.

References

21 U.S.C. 331(ddd), which prohibits the manufacture or the introduction or delivery for introduction into interstate commerce of a rinse-off cosmetic containing intentionally-added plastic microbeads, defines a plastic microbead as any solid plastic particle less than five millimeters in size intended to be used to exfoliate or cleanse the human body or any part thereof, and provides that rinse-off cosmetic includes toothpaste. law.cornell.edu

21 CFR 740.1, which requires the label of a cosmetic product to bear a warning statement whenever necessary or appropriate to prevent a health hazard that may be associated with the product. law.cornell.edu

Written from federal statute and from measured catalog data, not from a formulation bench. Whether a particular particle is a plastic microbead within 21 U.S.C. 331(ddd) is a question about that particle and its purpose. Nothing here is a determination about a specific exfoliant or a specific formula.