ATNC analysis: quantifying nitrosamines at trace levels

The presence of nitrosamines at trace levels is a critical issue for manufacturers in the pharmaceutical, biopharmaceutical, and cosmetics sectors. Whether it involves risk assessment, compliance testing, an investigation in the event of a dispute, a stability study, or a suspected container-content interaction, the detection and quantification of nitrosamines require high analytical performance. ATNC analysis makes it possible to assess total nitrosamines, in addition to approaches targeted at specific compounds or NDSRIs. This approach is particularly relevant when several precursors or formation pathways are being considered, or when a broad screening is needed before targeted quantification. To explore further the regulatory and analytical challenges related to nitrosamines, it is essential to have a strategy adapted to the matrix, the trace level sought, and quality expectations.

The challenges encountered differ depending on whether the sample is an active ingredient, an excipient, a finished product, a packaging component or a cosmetic formulation. Manufacturers often have to strike a balance between a rapid screening approach and a validated quantitative method, with high expectations in terms of sensitivity, selectivity and robustness. In some cases, the source of the risk may also be linked to container-content interactions, requiring a broader investigation into nitrosamine formation pathways.

Measuring nitrosamine traces requires highly sensitive equipment and rigorous sample preparation. Depending on the analytical objectives, the laboratory relies on UPLC-MS/MS, Orbitrap-type LC-HRMS, LC-QTOF, GC-MS and GC-MS/MS systems. These resources make it possible to carry out qualitative and semi-quantitative screening, structural confirmation and targeted assays with estimated quantification limits ranging from 0.1 ppb to a few ppb depending on the compounds and matrices. For very specific measurement needs, a complementary Drx Quantification approach can also illustrate the laboratory's ability to handle advanced quantification challenges.

The laboratory relies on a technical team of more than 140 people, including a team dedicated to nitrosamine analysis, and on a 5,200 m² analytical platform integrating multiple chromatographic and spectrometric technologies. This organization makes it possible to handle a wide range of requests: exploratory studies, targeted testing, method validation, analytical transfers and investigations on complex matrices. The cosmetic and dermocosmetic sectors can also benefit from complementary expertise on formulations and raw materials, notably through approaches such as Analyse Cosmetique Iso Tr 18818.

The laboratory implements a comprehensive approach to the analysis of nitrosamine traces: qualitative and semi-quantitative screening, targeted assay, method development and analytical validation according to ICH Q2 (R2). Services include, in particular, the search for unlisted nitrosamines following risk assessment, NDMA testing in a finished product, validation of very low quantification limits, as well as the analysis of total nitrosamines according to ATNC. Commonly investigated substances include NDMA, NDEA, NMBA, NEIPA, NDIPA, NPIP, NPYR, NMOR, NDELA, NDBA and even NDSRI-type impurities. This expertise is delivered in a GMP-compliant environment, with a dedicated team and methods adapted to the constraints of complex matrices, from raw materials to finished products.

analysis may focus on nitrosamines that are under regulatory monitoring or on specific compounds identified during the risk assessment. Frequently quantified substances include NDMA, NDEA, NEIPA, NDIPA, NMBA, NPIP, NMEA, NDBA, NDELA, NMOR and NPYR. The laboratory can also develop search strategies for unlisted nitrosamines and NDSRIs, with confirmation by high-resolution techniques followed by quantification using methods adapted to the target and the matrix.

Beyond the instrumentation, the reliability of the results depends on a methodical development process: choice of extraction protocol, management of matrix effects, selectivity against interferents, study of linearity, accuracy, precision, robustness and validation of the quantification limit. Methods are developed and validated according to ICH Q2 (R2), in a GMP-compliant environment. This organization makes it possible to secure both routine studies and more complex investigations, including in the context of release, quality deviation or dispute.

Choosing this laboratory means relying on a structure recognized for its high quality standards, GMP environment and ability to provide a tailor-made analytical response. The goal is not only to produce a result, but to help manufacturers make decisions quickly: confirm absence or presence, document non-compliance, compare several batches, validate a method, or guide a corrective action plan. For powder products or complex matrices in the beauty sector, related expertise such as Analyse Poudre Cosmetique can also complement the overall assessment.

The ATNC analysis is relevant when a broad view of total nitrosamines is required, particularly during risk assessment, initial screening, or exploratory investigation. A targeted analysis will then be preferred to identify and quantify specific compounds accurately, with performance suited to the expected thresholds. In practice, the two approaches are often complementary: ATNC to guide the strategy, then targeted nitrosamine quantification to document compliance and support decision-making.