Filter Forensics: A novel method for exploring exposure to particle-bound contaminants

加拿大人有三分之二的时间呆在家里，暴露在各种各样的污染物中。我们接触到的空气污染大多发生在建筑物内部，尤其是在我们的家中。尽管室内环境对人体健康很重要，但人们对它的研究相对较少。室内颗粒物（PM）暴露对健康的影响是重大的，给加拿大经济造成了数十亿美元的医疗保健费用。超过60%的加拿大家庭使用供暖、通风和空调（HVAC）过滤器，这为评估人体暴露于颗粒污染物提供了一个尚未开发的机会。虽然在科学和医学上对接触微粒的严重健康后果几乎没有怀疑，但室内的接触量和室内微粒的组成是进一步探索的成熟领域。评估室内颗粒的传统方法通常依赖于沉降尘埃样本或短期空气样本。沉淀的尘埃样本偏向于与较大颗粒相关的污染物，并且仅在空间上代表收集它们的房间/区域。短期空气样本通常只收集几分钟到几个小时的时间，因此收集的空气量很小。这些传统的采样方法捕捉室内颗粒浓度的快照，不允许详细的暴露分析。与这些方法不同的是，暖通空调过滤器可以长时间使用，并提供家中空气中颗粒的综合样本，从而提供与暴露相关的浓度。当与现场过滤器效率、运行时间和气流测量相结合时，对过滤器捕获的颗粒进行分析，为评估室内空气中颗粒结合污染物的浓度提供了新的机会。拟议研究的中心目标是通过比较详细的长期测试的过滤器测量值来探索这种创新采样方法的有效性，以及通过从家中回收过滤器并分析其上的灰尘来探索这种方法在法医环境中使用的实用性。将探索的具体污染物包括真菌、过敏原、黑碳和重金属。拟议办法的主要好处是通过了解我们接触严重污染物的情况来改善加拿大人的健康。拟议研究的另一个好处是开发一种低成本的方法来快速评估暴露热点，以及对野火、工业事故和洪水等特殊事件做出反应。这项研究将导致对室内颗粒污染物浓度的变革性理解。

Canadians spend two-thirds of their time in their homes and are exposed to a variety of contaminants in residential settings. Most of our exposure to air pollution occurs inside of buildings, and particularly in our homes. Despite its importance to human health, the indoor environment is relatively unstudied. The health consequences of indoor particulate matter (PM) exposure are significant and cost the Canadian economy billions of dollars in health care costs. The heating, ventilation, and air conditioning (HVAC) filters present in over 60% of Canadian households represent an untapped opportunity to assess human exposure to particle-bound contaminants. Although there is little scientific and medical doubt of the serious health consequences of exposure to particles, the amount of exposure that occurs indoors and the composition of indoor particles are areas ripe for further exploration. Traditional methods of assessing indoor particles typically rely on either settled dust samples or short-term air samples. Settled dust samples are biased towards contaminants associated with larger particles and are only spatially representative of the room/area from which they are collected. Short-term air samples are typically only collected for periods ranging from minutes to a few hours and thus collect a small volume of air. These traditional sampling approaches capture a snapshot of indoor particle concentrations and do not allow for detailed exposure analysis. Unlike these approaches, HVAC filters are in place for extended periods of time and provide an integrated sample of the airborne particles present in homes and thus provide an exposure-relevant concentration. When coupled with in-situ filter efficiency, runtime, and airflow measurements, analysis of the particles captured by filters offer a novel opportunity to assess the airborne concentrations of particle-bound pollutants in homes.The central objectives of the proposed research are both to explore the validity of this innovative sampling approach by comparing filter measurements from detailed long term testing, as well as explore the utility of this approach if it were used in a forensics context by recovering filters from homes and analyzing the dust on them. The specific contaminants that will be explored include fungi, allergens, black carbon, and heavy metals. The central benefit of the proposed approach is to improve the health of Canadians by understanding our exposure to serious contaminants. An additional benefit of the proposed research is to develop a low-cost approach for rapidly assessing exposure hot spots as well as respond to extraordinary events such as wildfires, industrial accidents, and flooding. This research will result in a transformative understanding of concentrations of indoor particle-bound contaminants.