Inhalation of the chemical warfare agent sulfur mustard (SM) is associated with severe acute and long-term pulmonary dysfunctions and health effects. The still not completely elucidated molecular toxicology and a missing targeted therapy emphasize the need for further research. However, appropriate human data are extremely rare. In vivo animal experiments are often regarded as gold standard in toxicology but may exhibit significant differences compared to the human pulmonary anatomy and physiology. Thus, alternative in vitro exposure methods, adapted to the human in vivo situation by exposing cells at the air-liquid interface (ALI), are complimentary approaches at a cellular level. So far, it is unclear whether the enhanced experimental complexity of ALI exposure, that is potentially biologically more meaningful, is superior to submerged exposures which are typically performed.

Aim of our study was the evaluation of an appropriate in vitro exposure system (CULTEX^® Radial Flow System (RFS) equipped with an eFlow^® membrane nebulizer) for the exposure of cultivated human lung cells (A549) with SM under ALI conditions. Cellular responses (i.e. cell viability) and formation of SM-specific DNA-adducts were investigated and compared between ALI and submerse SM exposures.

Our results proved the safe applicability of our ALI exposure system setup. The aerosol generation and subsequent deposition at the ALI were stable and uniform. The technical CULTEX^® RFS setup is based on ALI exposure with excess of aerosol from that only some is deposited on the cell layer. As expected, a lower cytotoxicity and DNA-adduct formation were detected when identical SM concentrations were used compared to experiments under submerged conditions. A distinct advantage of SM-ALI compared to SM-submerse exposures could not be found in our experiments. Though, the CULTEX^® RFS was found suitable for SM-ALI exposures.

吸入化学战剂硫芥末（SM）与严重的急性和长期肺功能障碍和健康影响有关。仍未完全阐明的分子毒理学和缺少的靶向疗法强调了进一步研究的必要性。但是，适当的人类数据极为罕见。体内动物实验通常被视为毒理学的金标准，但与人的肺部解剖学和生理学相比，可能表现出显着差异。因此，适用于人类体内的替代性体外暴露方法通过在气液界面（ALI）处暴露细胞来解决这种情况，是在细胞水平上的补充方法。到目前为止，还不清楚增强的ALI暴露的实验复杂性（可能在生物学上更有意义）是否优于通常进行的淹没暴露。

我们研究的目的是适当的评价体外曝光系统（CULTEX ^®配备径向流系统（RFS）的的eFlow ^®膜雾化器），用于培养的人类肺细胞的ALI条件下曝光（A549）与SM。研究了细胞反应（即细胞活力）和SM特异性DNA加合物的形成，并比较了ALI和潜水SM暴露之间的关系。

我们的结果证明了我们的ALI曝光系统设置的安全适用性。气溶胶的产生和随后在ALI处的沉积是稳定且均匀的。技术CULTEX ^® RFS设置是基于ALI曝光用过量的气溶胶从只有某些沉积在细胞层上。如所预期的，与淹没条件下的实验相比，当使用相同的SM浓度时，检测到较低的细胞毒性和DNA加合物的形成。与SM潜水相比，SM-ALI的独特优势无法在我们的实验中找到。虽然，CULTEX ^® RFS发现适用于SM-ALI风险。