No poison. Zirconia is a white solid, which is harmless to the body, so the cubic zirconia earrings synthesized by Laofengxiang Silver 925 are nontoxic. Lao Fengxiang, a listed company, is one of the top 500 enterprises in China. It is a century-old national brand, a famous jewelry brand in China and a classic jewelry brand spanning three centuries in China.