San Diego State University Research Foundation, San Diego, California, USA.
San Francisco Estuary Institute, Richmond, California, USA.
Integr Environ Assess Manag. 2021 Nov;17(6):1179-1193. doi: 10.1002/ieam.4461. Epub 2021 Jul 20.
Wildfires can be extremely destructive to communities and ecosystems. However, the full scope of the ecological damage is often hard to assess, in part due to limited information on the types of chemicals introduced to affected landscapes and waterways. The objective of this study was to establish a sampling, analytical, and interpretive framework to effectively identify and monitor contaminants of emerging concern in environmental water samples impacted by wildfire runoff. A nontargeted analysis consisting of comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC × GC/TOF-MS) was conducted on stormwater samples from watersheds in the City of Santa Rosa and Sonoma and Napa Counties, USA, after the three most destructive fires during the October 2017 Northern California firestorm. Chemicals potentially related to wildfires were selected from the thousands of chromatographic features detected through a screening method that compared samples from fire-impacted sites versus unburned reference sites. This screening led to high confidence identifications of 76 potentially fire-related compounds. Authentic standards were available for 48 of these analytes, and 46 were confirmed by matching mass spectra and GC × GC retention times. Of these 46 compounds, 37 had known commercial and industrial uses as intermediates or ingredients in plastics, personal care products, pesticides, and as food additives. Nine compounds had no known uses or sources and may be oxidation products resulting from burning of natural or anthropogenic materials. Preliminary examination of potential toxicity associated with the 46 compounds, conducted via online databases and literature review, indicated limited data availability. Regional comparison suggested that more structural damage may yield a greater number of unique, potentially wildfire-related compounds. We recommend further study of post-wildfire runoff using the framework described here, which includes hypothesis-driven site selection and nontargeted analysis, to uncover potentially significant stormwater contaminants not routinely monitored after wildfires and inform risk assessment. Integr Environ Assess Manag 2021;17:1179-1193. © 2021 SETAC.
野火对社区和生态系统具有极强的破坏性。然而，由于受野火影响的景观和水道中引入的化学物质类型的信息有限，生态破坏的全面范围通常难以评估。本研究的目的是建立一个采样、分析和解释框架，以有效识别和监测受野火径流影响的环境水样中新兴关注污染物。在美国加利福尼亚州圣罗莎市和索诺玛县、纳帕县的流域进行了暴雨水样的非靶向分析，包括全面二维气相色谱与飞行时间质谱联用 (GC×GC/TOF-MS)。这些水样是在 2017 年 10 月北加州山火风暴中三次最具破坏性的火灾之后采集的。通过一种筛选方法，从通过比较受火灾影响的地点与未燃烧的参考地点的样品检测到的数千个色谱特征中选择与野火相关的化学物质。这种筛选方法可高度置信地鉴定出 76 种潜在的与野火相关的化合物。这些分析物中有 48 种有现成的标准品，其中 46 种通过匹配质谱和 GC×GC 保留时间得到确认。在这 46 种化合物中，有 37 种已知的商业和工业用途是塑料、个人护理产品、农药的中间体或成分，也是食品添加剂。有 9 种化合物没有已知的用途或来源，可能是天然或人为材料燃烧产生的氧化产物。通过在线数据库和文献综述对与 46 种化合物相关的潜在毒性进行了初步检查，表明数据可用性有限。区域比较表明，更多的结构破坏可能会产生更多独特的、潜在与野火相关的化合物。我们建议进一步研究使用这里描述的框架进行的野火后径流，包括基于假设的地点选择和非靶向分析，以发现通常不在野火后监测的潜在重要暴雨污染物，并为风险评估提供信息。《综合环境评估与管理》2021 年；17：1179-1193。© 2021 SETAC。
