REACH testing for water-electroplated pearlescent chromium on plastic components verifies that pearl-chrome plated parts comply with EU Regulation (EC) No 1907/2006, covering SVHC screening, Annex XVII restricted substances such as hexavalent chromium and nickel, phthalates, and PAHs. This article explains the coating system, sampling requirements, test items, analytical methods, and typical applications to help manufacturers of plated plastic trims achieve compliance for the European market.
Technical Overview
Pearlescent chromium (pearl chrome, satin chrome) is a decorative metallic finish widely applied to plastic substrates such as ABS and PC/ABS through wet, aqueous electroplating, commonly referred to as water plating. Unlike vacuum metallizing, water plating builds a genuine metallic stack: after surface conditioning and etching, the plastic is activated with a palladium-based catalyst, coated with an electroless nickel or copper strike layer, followed by electrolytic acid copper for leveling. The characteristic pearl appearance is produced by a satin (pearl) nickel layer containing finely dispersed non-conductive co-deposit particles, sealed by a thin chromium top layer, which in modern lines is typically deposited from a trivalent chromium bath.
Because the plating chemistry is complex, REACH compliance must be demonstrated for the finished article, not only for the base polymer. REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals, Regulation (EC) No 1907/2006) imposes three main obligations relevant to plated plastic components: communication and notification duties for Substances of Very High Concern (SVHC) on the ECHA Candidate List above 0.1% weight-by-weight; compliance with Annex XVII restriction entries (for example, nickel release from skin-contact articles, cadmium, lead, phthalates, PAHs, and PFOA); and awareness of Annex XIV authorisation requirements, since chromium trioxide and the acids generated from it, historically used in chromic acid etching and hexavalent plating baths, are subject to authorisation for electroplating uses.
Typical chemical risk points in this product category include residual hexavalent chromium from chromic-acid etching or aged passivation layers, nickel release from skin-contact surfaces, phthalate plasticizers in the plastic substrate or in elastomeric gaskets, PAHs in process oils and carrier materials, lead and cadmium from legacy pigments and stabilizers, bisphenol A residues from polycarbonate substrates, and chlorinated paraffins from flame-retarded grades. A structured REACH test program performed by accredited third-party laboratories addresses all of these.
Testing Samples
Coating Layer Sample
The metallic stack is sampled by mechanically scraping or milling the plated surface, ideally collecting 100 to 500 mg of the etch residue, nickel, and chromium layers. This fraction is critical for hexavalent chromium determination and for detecting SVHC carry-over from pre-treatment chemistry such as chromic acid etch or passivation solutions.
Substrate Homogeneous Material Sample
The plastic base material should be submitted as a separate homogeneous fraction, either as cut coupons, milled granules, or un-plated runner material of identical grade, with a recommended quantity of at least 10 g per material for a full SVHC screen. Homogeneous sampling ensures that phthalates, bisphenol A, chlorinated paraffins, and metal-containing additives are correctly attributed to the polymer rather than dilution-averaged against the coating.
Whole Component Sample
For articles with prolonged skin contact, such as cosmetic closures, watch trims, and gear-knob inserts, two to three complete parts should be submitted for nickel release testing, since the release rate must be measured on the finished, coated surface as placed on the market. Samples must not be pre-cleaned with aggressive organic solvents, as these may artificially strip target analytes.
Testing Items
A comprehensive REACH assessment for water-plated pearlescent chromium on plastics normally includes the following groups of parameters:
- SVHC screening against the current ECHA Candidate List (updated approximately every six months, exceeding 240 substances), with results compared against the 0.1% w/w threshold per homogeneous material.
- Hexavalent chromium (Cr(VI)) content and extractable concentration in the coating and at the plastic-metal interface.
- Total elemental quantification of chromium, nickel, lead, cadmium, arsenic, and mercury in coating and substrate fractions.
- Nickel release rate for skin-contact articles under Annex XVII Entry 27, with the limit of 0.5 µg/cm²/week for coated articles intended for direct and prolonged skin contact.
- Phthalates (DEHP, DBP, BBP, DIBP, DINP, DIDP, DNOP, and related esters) restricted under Annex XVII Entries 51 and 52 at 0.1% in plasticized material.
- Polycyclic aromatic hydrocarbons (PAHs) in plastic and rubber fractions under Annex XVII Entry 50, with the 1 mg/kg limit for skin-contact articles.
- PFOA and related substances under Annex XVII Entry 68, plus PFOS, short-chain and medium-chain chlorinated paraffins as frequent SVHC findings.
- Bisphenol A, remaining relevant anilines, and other organotin or boron SVHCs flagged by the latest Candidate List update.
Testing Methods
Sample preparation typically involves cryogenic milling of polymers, mechanical scraping of plated layers, and microwave-assisted acid digestion (using nitric, hydrochloric, and where necessary hydrofluoric acid) to bring the metallic fractions completely into solution.
- Metals and total chromium are quantified by ICP-OES or ICP-MS following procedures aligned with IEC 62321-5; EN 71-3 migration data can be added for toy-adjacent applications.
- Hexavalent chromium is determined by boiling-water extraction followed by UV-Vis spectrophotometry with 1,5-diphenylcarbazide colorimetry, following the principles of IEC 62321-7-1 and IEC 62321-7-2 for coatings and polymeric materials; spot-test screening may be used as an initial triage step.
- Phthalates are extracted with dichloromethane or tetrahydrofuran and analyzed by GC-MS in line with IEC 62321-8 and EN 14372 practices.
- SVHC organic screening combines GC-MS and LC-MS target analysis with unknown-peak library matching, supplemented by ICP-MS element screening and, where required, substance-specific speciation.
- PAHs are extracted with toluene and quantified by GC-MS according to approaches consistent with the GS PAK scheme.
- Nickel release is measured after one week in artificial perspiration per EN 1811, with coated articles subjected to the wear-and-corrosion pretreatment described in EN 12472.
Results are reported in mg/kg (or % w/w) per homogeneous material, compared against 0.1% w/w (1000 mg/kg) for SVHC and against the specific limit values of each Annex XVII entry. Where hexavalent chromium is non-detectable, the laboratory states the method detection limit, since some downstream specifications request quantitative LOQ values.
Applications
REACH-compliant pearlescent chromium plating on plastics is used across many decorative and functional product sectors:
- Automotive interior and exterior trim: gear-knob inserts, dashboard accents, door-handle bezels, grille ornaments, wheel emblems, and badge lettering.
- Cosmetics and personal-care packaging: lipstick mechanisms, compact closures, perfume caps, pump collars, and mascara components, where nickel release limits are decisive.
- Consumer electronics and home appliances: decorative bezels, control knobs, trim rings, and logos on housings.
- Sanitary ware and furniture hardware: faucet handles, lever inserts, furniture trims, and hooks.
- Fashion accessories: belt buckles, watch cases and bracelets, eyewire trims, and leather-goods hardware with prolonged skin contact.
- Luggage and sporting goods: trolley fittings, zipper pullers, handle trims, and branded metal-look ornaments.
FAQ
What is the difference between SVHC testing and Annex XVII restricted-substance testing?
SVHC testing screens for Candidate List substances above 0.1% w/w, which triggers communication duties under Article 33, SCIP notification, and possible ECHA notification above one tonne per year, but does not ban the substance. Annex XVII testing verifies compliance with binding restriction limits, such as nickel release, phthalates, or PAHs, and non-compliance means the article cannot be placed on the EU market.
We use a trivalent chromium bath. Does the part still need Cr(VI) testing?
Yes. Even with a trivalent top layer, hexavalent chromium can originate from chromic-acid etching of the plastic, hexavalent passivation, or oxidative conversion of trivalent deposits during aging, storage, or UV exposure. Cr(VI) verification on the finished article remains a standard requirement of most European customer specifications.
How much sample is needed and how long does testing take?
A typical program requires 10 to 20 g per homogeneous material plus plated parts for coating work and nickel release. Standard turnaround at accredited third-party laboratories is five to seven working days for targeted tests, and seven to ten working days for a full SVHC screen, excluding repeat or confirmation analysis.
How long is a REACH test report valid?
REACH does not assign an official validity period; a report reflects the submitted sample at the time of testing. Because the Candidate List is updated twice per year, most supply chains require re-testing or re-evaluation annually or upon every list update, material change, or plating process modification.
What must be done if an SVHC exceeds 0.1% w/w?
The supplier must provide adequate information to professional customers on request, notify the article in the SCIP database, and notify ECHA if the SVHC exceeds one tonne per year in that article, unless exposure can be excluded. Root-cause analysis usually points to substrate additives or pre-treatment chemistry, which can often be substituted.