Analysis of N-nitrosamines and N-nitrosatable substances from baby bottle rubber teats by liquid chromatography tandem mass spectrometry

Abstract

A simple and sensitive method based on liquid chromatography-atmospheric pressure chemical ionisation-tandem mass spectrometry (LC-APCI-MS/MS) was developed and validated to determine the levels of 13N-nitrosamines and N-nitrosatable substances migrated from rubber teats into artificial saliva. The migration test from rubber teats was conducted at 40 °C and for 24 h in artificial saliva, and the migrated artificial saliva solution was analysed by liquid chromatography tandem mass spectrometry (LC-MS/MS) without further extracting steps. The sensitivity of N-nitrosamines was examined by applying atmospheric chemical ionisation and electrospray ionisation to optimise the mass spectrometric conditions, and the atmospheric chemical ionisation (APCI) mode exhibited 1.6–19 times higher sensitivity. Method validation showed acceptable linearity, precision, and accuracy, and the detection and quantification limits were 0.07–0.35 and 0.24–1.1 μg kg⁻¹, respectively. The developed liquid chromatography-atmospheric chemical ionisation-tandem mass spectrometry method was applied to 39 domestic and imported rubber teats. From 39 samples, N-nitrosamines [N-nitrosodimethylamine (NDMA), N-nitrosomorpholine (NMOR), and N-nitroso n-methyl N-phenylamine (NMPhA)] were detected in 30 samples, with N-nitrosatable substances in 17 samples give rise to NDMA, NMOR, and N-nitrosodiethylamine. However, the levels were below the specific migration limit of Korean Standards and Specifications for Food Containers, Utensils, and Packages and EC Directive 93/11/EEC.

Keywords:

• N-nitrosamines
• N-nitrosatable substances
• high-performance liquid chromatography-atmospheric pressure-tandem mass spectrometry
• high-performance liquid chromatography-electrospray ionisation-tandem mass spectrometry
• rubber teat

Authors’ contributions

Conceptualisation: Joung Boon Hwang and Soonho Lee; investigation: Joung Boon Hwang, Jung Eun Lee, and Eunbi Kim; methodology: Joung Boon Hwang, Jung Eun Lee, Eunbi Kim, Kwonyong Eom, and Hyun-Ah Kim; formal analysis: Joung Boon Hwang, Jung Eun Lee, and Eunbi Kim; writing—original draft: Joung Boon Hwang; writing-review and editing: Hyun-Ah Kim and Soonho Lee; supervision: Soonho Lee.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The authors declare that all data supporting the findings of this study are available within the article.

Additional information

Funding

This work was supported by the Korea Ministry of Food and Drug Safety under Grant [21161MFDS018].