Nickel and Formaldehyde Limits in Bra Hardware and Fabrics
Two substances account for most chemical failures in bra programmes, and neither is exotic. Nickel comes from the metal in the hook-and-eye closure and any metallic trim or slider. Formaldehyde comes from resin finishes on elastics, tapes and prints, and from dye-fixing agents. Both are restricted, both are testable, and both are usually missed because buyers test the shell fabric and assume the rest follows. It does not.
Nickel: Where the Limit Applies
Under entry 27 of Annex XVII to EU REACH, articles intended to come into direct and prolonged contact with the skin may not release nickel at more than 0.2 micrograms per square centimeter per week. A bra closure sits against the back for hours at a time and is squarely in scope. The reference test method is EN 1811, which immerses the article in artificial sweat and measures released nickel. Where the metal part is coated, EN 12472 is applied first to simulate wear and corrosion, and then EN 1811 is run on the exposed article. Screening by XRF is useful for sorting parts quickly but is not a substitute for a migration test.
Specifying Compliant Hardware
Hook-and-eye tape is normally supplied with steel or brass hooks and a plated finish. Ask the trim supplier for an EN 1811 report per hardware lot, not per style, because plating baths are the variable. Options that reduce risk: nickel-free plating systems, physical vapor deposition coatings, or stainless steel in a grade with low release. Also specify corrosion resistance, since a closure that corrodes will release more metal over the life of the garment: a neutral salt spray test per ISO 9227 for 24 hours with no base metal corrosion is a reasonable requirement, plus a perspiration soak followed by visual inspection for discoloration.
Formaldehyde: Sources and Limits
Formaldehyde in a bra rarely comes from the main fabric. It comes from resin finishes applied to elastics, hook tape and woven labels to prevent shrinkage, and from fixing agents used in printing and dyeing. The standard test methods are EN ISO 14184-1, which measures free and hydrolyzed formaldehyde by water extraction, and ISO 14184-2, which measures released formaldehyde by vapor absorption. Use part 1 for specification and part 2 when a complaint concerns odor or irritation in wear. The most widely used commercial limit is the OEKO-TEX Standard 100 value of 75 mg per kg for class II articles worn next to skin, and 20 mg per kg for class I. The EU has also introduced a REACH restriction on formaldehyde in clothing at 75 mg per kg that phases in over the second half of the 2020s, so confirm the current applicable date with your laboratory rather than assuming it is already in force.
Other Market Limits
Japan applies its Household Goods Regulation, commonly referred to as Law 112, with a limit of 75 ppm for textiles worn next to skin and 20 ppm for infants, tested by the acetylacetone method described in JIS L 1041. Some US retailers apply their own restricted substances list with a formaldehyde limit in the same range. If you sell into more than one region, set the specification to the strictest applicable limit and test once.
Which Components to Sample
Test formaldehyde on every textile and foam component separately: shell, lining, elastic band, hook tape fabric, shoulder strap elastic, printed logo area, care label, thread and the pad foam. Test nickel on every metal component: hooks, eyes, sliders, rings and any metallic logo. The pad foam is frequently overlooked and is a common source of both formaldehyde and volatile organic readings.
Setting the Testing Frequency
Run a full component panel at development and at pre-production approval. On bulk, test formaldehyde once per fabric lot and once per trim lot, and test nickel on each hardware delivery, since trim is often bought in from a second supplier with its own lot numbering. Require the laboratory report to name the component and the lot, and reject any report that describes the sample only as fabric.
These are small tests with short turnaround. Run early enough and they are a line item; run late and they are a relabelling or a recall.
