Study of No Observed Adverse Effect Level of Nickel and Its Preliminary Evaluation Biocompatibility / 中国医疗器械杂志

The purpose of this study was to investigate the NOAEL of the nickel ion and provide with basic data for the biological evaluation of those medical devices containing nickel. Five groups SD rats were repeatedly exposed during 14 d respectively to nickel at first stage doses of 4.9, 3.7, 2.5 mg/(kg.d), and the second stage doses of 1.2, 0.25 mg/(kg.d) by the intravenous route. The results showed that the NOAEL of nickel ion is 0.25 mg/(kg.d) for SD rats, and the result was verified by subchronic systemic toxicity test of nickel alloy. The threshold of toxicological concern (TTC) of nickel is 150 μg/d (based on application of 100-fold uncertainty factor and a body weight of 60 kg)deduced by these data.

Application of the Threshold of Toxicological Concern (TTC) to Biological Evaluation of Medical Devices / 中国医疗器械杂志

The threshold of toxicological concern (TTC), a risk estimation method based on compound structurally-related toxicity data, has been widely used by many countries and regions for the safety risk assessment of food packaging materials and additives etc. Toxicological risk estimation is of importance in the biological evaluation of medical devices. Application of the TTC approach to leachable from medical devices may reduce or replace some unnecessary biocompatibility tests, but consideration should be taken for contact duration and route differences, which could affect the applicability of TTC. We herein focused on analyzing the eligibility of TTC for its further application in biological evaluation of medical devices.