School of Environmental Sciences, University of Guelph, Guelph, ON, Canada.
Environ Sci Pollut Res Int. 2021 Apr;28(16):20883-20893. doi: 10.1007/s11356-020-12061-8. Epub 2021 Jan 6.
Firefighting water additives are used to increase the rate at which fires can be extinguished. The majority of ecotoxicological research has focused on firefighting formulations containing perfluorinated compounds as additives, due to the persistence and bioaccumulative nature of the perfluorinated constituents. A number of relatively new additives have come on the market to replace the products containing perfluorinated compounds. The potential effect of these new additives on the environment has been largely unstudied. This study investigated the toxicity of six firefighting water additives: Eco-Gel™, ThermoGel 200L™, FireAde™, Fire-Brake™, Novacool Foam™, and F-500™ to terrestrial biota. Terrestrial organisms could be exposed to firefighting water additives through leaching into soil and/or runoff following a firefighting event or through direct aerial application during a forest fire. Toxicity to three plant species was assessed through seedling germination and emergence tests: Fagopyrum esculentum (buckwheat), Raphanus raphanistrum subsp. sativus (radish), and Rudbeckia hirta (black-eyed Susan). The effects of firefighting water additives on three soil invertebrates, the collembolan Folsomia candida, the earthworms Eisenia andrei, and Dendrodrilus rubidus, were also investigated using static acute tests to estimate EC/LCs. The concentration that resulted in a 50% reduction in survival (LC) for the acute toxicity tests conducted with F. candida ranged from 3 (Eco-Gel) to 0.175% (Novacool) by volume. Comparatively, the acute toxicity of two firefighting water additives to D. rubidus could not be determined, as a 50% reduction in survival was not observed. A number of firefighting water additives were found to pose a hazard to terrestrial organisms based on a worst-case exposure scenario of direct application at the greatest recommended application rate for a class A fire (e.g., wood, paper). The firefighting water additive F-500 was found to pose a hazard (HQ ≥ 1) for all species tested, except for the acute test conducted with D. rubidus. Comparatively, Eco-Gel posed a hazard for only the acute and chronic tests with F. candida. This study represents the first comparative deterministic risk assessment of firefighting water additives to terrestrial ecosystems.
消防水添加剂用于提高灭火速度。由于全氟化合物的持久性和生物累积性，大多数生态毒理学研究都集中在含有全氟化合物作为添加剂的消防配方上。一些相对较新的添加剂已经进入市场，以取代含有全氟化合物的产品。这些新添加剂对环境的潜在影响在很大程度上尚未得到研究。本研究调查了六种消防水添加剂对陆地生物群的毒性：Eco-GelTM、ThermoGel 200LTM、FireAdeTM、Fire-BrakeTM、Novacool FoamTM 和 F-500TM。陆生生物可能通过消防事件后浸出到土壤中和/或径流，或通过森林火灾期间的直接空中应用，接触到消防水添加剂。通过幼苗发芽和出苗试验评估了三种植物物种的毒性：苦荞麦（Fagopyrum esculentum）、萝卜（Raphanus raphanistrum subsp. sativus）和黑眼苏珊（Rudbeckia hirta）。还使用静态急性试验研究了六种消防水添加剂对三种土壤无脊椎动物，即跳虫（Folsomia candida）、蚯蚓（Eisenia andrei）和红线蛭（Dendrodrilus rubidus）的影响，以估计 EC/LCs。急性毒性试验中 F. candida 的浓度导致 50%的存活率降低（LC），体积浓度范围为 3%（Eco-Gel）至 0.175%（Novacool）。相比之下，由于没有观察到 D. rubidus 存活率降低 50%，因此无法确定两种消防水添加剂对 D. rubidus 的急性毒性。根据直接应用于 A 级火灾（例如木材、纸张）最大推荐应用率的最坏情况暴露情景，一些消防水添加剂被发现对陆地生物构成危害。消防水添加剂 F-500 被发现对所有测试物种构成危害（HQ≥1），除了对 D. rubidus 进行的急性测试。相比之下，Eco-Gel 仅对 F. candida 的急性和慢性测试构成危害。本研究代表了对陆地生态系统消防水添加剂的首次比较确定性风险评估。
