Nickel is a strong sensitizer and can cause allergic reactions if present in articles that come into direct and prolonged contact with the skin. Exposure to lead is harmful for human health and cadmium is harmful to human health, because it accumulates in the body and can damage organs and it may cause cancer. EU REACH Annex XVII request that nickel release from any post assemblies which are inserted into pierced ears and other pierced parts of the human body less than 0,2 μg/cm²/week and nickel release from the parts of these articles coming into direct and prolonged contact with the skin less than 0,5 μg/cm²/week, cadmium in the metal parts of jewellery less than 0.01%, lead in the jewellery less than 0.05%. BACL suggest relevant enterprises pay close attention to the above information and strengthen quality management to ensure product compliance.