Migration characteristics and risk assessment of chemical hazardous substances in infant teether toys

Teether is a special toy used for infants oral contact. In this paper, a residual and migration detection method was developed using gas chromatography-tandem mass spectrometry for 20 screened hazardous substances in teethers. Fifteen substances were detected in 59 samples, with residual amounts and detection rates ranging from 0.01 mg⋅kg^-1 to 106.15 mg⋅kg^-1 and from 3.39 % to 84.7 % respectively. Then, 12 substances were detected in simulated saliva at migration levels ranging from 0.0143 mg⋅kg^-1 to 20.03 mg⋅kg^-1, with detection rates ranging from 1.69 % to 76.3 %. Statistically, the average migration rate of each substance ranged from 8.18 % to 53.28 % depending on the properties of the substance and the sample. The exposure risk of infants to teethers was evaluated separately for two age groups. The hazard quotient (HQ) and hazard index (HI) values for the analytes were higher in the 3-12-month age group than in the 12-24-month age group. The HQ values of triphenylphosphine oxide, benzocaine, and N-methylformanilide were relatively high, with averages of 1.2 × 10^-2, 2.5 × 10^-3, and 1.6 × 10^-3, respectively, and the max HI of the 12 substances was 0.04. The HI and HQ values of the analytes were all below 1, indicating that the non-carcinogenic risks of analytes in teethers are at an acceptable level.