don’t be ‘mis–Lead’

Falling into line with lead content rules and regulations for jewellery is a tricky business. TIM SMITH, account manager for AnchorCert Anlaytical, sounds a note of caution on some of the methods being used out there.

Throughout the supply chain for jewellery, watches and fashion accessories, companies are spending an increasing amount of money on testing to ensure their products comply with the latest safety requirements. Through a combination of tight specifi cations, imposing responsibilities for compliance on the manufacturer or wholesaler and random testing, retailers and importers establish a programme of ‘due diligence’. This provides reassurance and protects the fi nal consumer and the reputation of the business. However, such confi dence can be misplaced and the high spend on testing rendered completely worthless if the items are not being tested to the required compliance level or by the appropriate method.

Since the enforcement of the REACH (Restriction, Evaluation and Authorisation of Chemicals) Regulation for lead on 9th October 2013, it has become apparent that some laboratories are using wholly inappropriate methods for the determination of lead content, most particularly in glass stones and decorative components. Tim Smith, account manager for The Laboratory, has encountered this issue on previous occasions, but since October it is a regularly re-visited subject.

Tim says: “Unlike nickel release, the method for testing for lead content to ensure compliance is not prescribed by the Regulation. Laboratories can apply whatever method they deem to be appropriate and this has led to obvious confusion and inconsistencies in test results for lead content.

“The compliance level is less than 0.05% (less than 500ppm) which is very low. Accuracy is everything and this can only be achieved by using an appropriate method which determines all of the lead present. We are aware that some laboratories are using the American Environmental Protection Agency (EPA) Method 3050B – acid digestion of sediments, soil and sludge which is completely unsuitable for glass, ceramics and compounds with a silicate lattice because of incomplete lead extraction.

“Customers place their trust in their chosen test supplier to apply a suitable method of analysis, but if an inappropriate analytical technique is used, this could render the test report meaningless and worthless. In these circumstances suppliers could fi nd that they are allowing non-compliant products into the market despite having had them tested in good faith. A court of law would be unlikely to support the use of EPA Method 3050B for demonstrating lead compliance with REACH for glass, ceramics and compounds with a silicate lattice.”

Given the well known dangers of lead, particularly in children’s’ products, this is a serious concern. Regular exposure to lead causes the toxin to gradually accumulate within the body which can cause severe developmental and behavioural problems. It is very unlikely that precious metal jewellery will contain more than the permitted levels of lead. However, coated base metal items, where the coating may easily wear off are always a risk and the nonmetallic parts, particularly glass stones, are definitely high risk as lead is commonly found in plastics, varnishes, paints, enamels, glass and lacquers.

AnchorCert Analytical interprets the legislation as requiring each material component to be tested separately, as is clearly the case for cadmium testing. Tests for both elements can then be carried out simultaneously. This is defi nitely worthwhile as individual paints, plastics and particularly stones are frequently found to be non compliant.

Method 3050B, which appears to be in common use by testing houses with a wide portfolio of non-specialist testing services was developed for environmental purposes to analyse sediments, soil and sludge. This method will not break down a silicate lattice sufficiently to enable complete lead extraction. The final analytical result could therefore seriously understate the lead content which may be heavily concentrated in the sample and which remains undissolved. Comparative testing by The Laboratory has consistently proven Method 3050B to be ineffective in checking for compliance with the lead regulation for glass stones by as much as 1,100 per cent.

Significantly more accurate techniques for testing glass decorative components utilise fusion or microwave digestion (e.g. EPA 3052, BS EN 62321:2009 _ RoHS ) using hydrofluoric acid. These techniques are complete dissolution techniques and provide very accurate results. This is the type of test procedure used by the Laboratory depending upon the nature of the sample. These techniques involve completely dissolving the sample and analysing the lead content in solution by ICPOES, typically with an accuracy of +/- 0.3 per cent. This approach will ensure that all lead is extracted, providing the Customer with full reassurance that their product is compliant and will not cause any harm.

Everyone in the supply chain is encouraged to ask questions and fully understand the consequences of the test methods that are being used, to ensure that their “due diligence” procedures are worth the money and bring proper protection to both the consumer and the supplier.

New Combined test for Crystal Glass

As compared to the metal parts of jewellery the health impact of lead exposure from crystals is considered relatively small, because there are indications of much lower migration rates. REACH Lead regulation therefore exempts crystals and precious and semiprecious stones from the restriction. Inevitably manufacturers and importers are keen to identify the components which can be classified as crystal glass as defined by the EU Directive of 1969 cited in the lead regulation.

In order to be classified as one of the categories of crystal glass the material must comply with three different criteria. It must contain oxides of lead, barium, zinc or potash combined or alone of at least 10 per cent, have a refractive index of above 1.52 and a density above 2.45 grams per square centimetre. Assay Office Birmingham has the specialist resources needed to offer this test, having the expertise and equipment to carry out both gemmological and chemical testing. Samples are subjected to assessment by both The Laboratory, who check the level of oxides, and the AnchorCert Gemmological Laboratory, who assess the relative density and refractive index and the final outcome are reported as “Crystal – Exempt” or “Glass” which may then be either “Compliant” or “Non Compliant”, depending upon the amount of lead contained.

AnchorCert Analytical has recently developed the test method and the software which will simultaneously analyse lead, cadmium, barium, potassium and zinc and quickly identify if glass stone, bead etc. meets the chemical criteria for it to be classified as crystal. This new combined test is available from January 2014. For more information please contact Tim Smith.