Finnish Institute for Verification of the Chemical Weapons Convention VERIFIN, Department of Chemistry, University of Helsinki, A.I. Virtasen aukio 1, FI-00014 Helsinki, Finland.
Finnish Environment Institute Syke, Marine and Freshwater Solutions Unit, Agnes Sjöbergin katu 2, FI-00790 Helsinki, Finland.
J Hazard Mater. 2024 Feb 15;464:132935. doi: 10.1016/j.jhazmat.2023.132935. Epub 2023 Nov 7.
During the World Wars large quantities of phenylarsenic chemical warfare agents (CWAs) were dumped in the Baltic Sea. Many transformation products of these chemicals have been identified, but the pathways that produce the found chemicals has not been investigated. Here we studied the biotic and abiotic transformation of phenylarsenic CWAs under oxic and anoxic conditions and investigated how the sediment bacterial communities are affected by CWA exposure. By chemical analysis we were able to identify seventeen CWA-related phenylarsenicals, four of which (methylphenylarsinic acid (MPAA), phenylthioarsinic acid (PTAA), phenyldithioarsinic acid (PDTAA) and diphenyldithioarsinic acid (DPDTAA)) have not been reported for marine sediments before. For the first time PTAA was verified from environmental samples. We also observed equilibrium reactions between the found transformation products, which may explain the occurrence of the chemicals. 16S rRNA-analysis showed that bacterial communities in sediments are affected by exposure to phenylarsenic CWAs. We observed increases in the amounts of arsenic-resistant and sulphur-metabolising bacteria. Different transformation products were found in biotic and abiotic samples, which suggests that bacteria participate in the transformation of phenylarsenic CWAs. We propose that methylated phenylarsenicals are produced in microbial metabolism and that chemical reactions with microbially produced sulphur species form sulphur-containing transformation products.
在两次世界大战期间，大量的苯胂化学战剂（CWA）被倾倒在波罗的海中。已经鉴定出这些化学物质的许多转化产物，但产生发现的化学物质的途径尚未得到研究。在这里，我们研究了有氧和缺氧条件下苯胂 CWA 的生物和非生物转化，并研究了 CWA 暴露如何影响沉积物细菌群落。通过化学分析，我们能够鉴定出十七种与 CWA 相关的苯胂化合物，其中四种（甲基苯胂酸（MPAA）、苯硫代胂酸（PTAA）、苯二硫代胂酸（PDTAA）和二苯二硫代胂酸（DPDTAA））以前在海洋沉积物中没有报道过。PTAA 首次从环境样品中得到验证。我们还观察到发现的转化产物之间的平衡反应，这可能解释了这些化学物质的存在。16S rRNA 分析表明，沉积物中的细菌群落受到苯胂 CWA 暴露的影响。我们观察到耐砷和硫代谢细菌的数量增加。在生物和非生物样本中发现了不同的转化产物，这表明细菌参与了苯胂 CWA 的转化。我们提出，甲基化苯胂化合物是在微生物代谢中产生的，并且与微生物产生的硫物种的化学反应形成含硫转化产物。
