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

加拿大人有三分之二的时间待在家里，暴露在住宅环境中的各种污染物中。我们暴露在空气污染中的大部分都发生在建筑物内，特别是在我们的家里。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巨大的，并给加拿大经济造成了数十亿美元的医疗费用。 超过60%的加拿大家庭使用的供暖、通风和空调(HVAC)过滤器是评估人类暴露在颗粒物结合污染物中的一个尚未开发的机会。尽管科学和医学上对暴露在颗粒物中的严重健康后果几乎没有疑问，但室内暴露的量和室内颗粒物的组成是进一步探索的成熟领域。评估室内颗粒物的传统方法通常依赖于已确定的粉尘样本或短期空气样本。尘埃样本偏向于与较大颗粒相关的污染物，仅在空间上代表收集尘埃的房间/区域。短期空气样本通常只收集几分钟到几个小时不等的时间，因此收集的空气量很小。这些传统的采样方法捕获了室内颗粒物浓度的快照，不允许进行详细的暴露分析。与这些方法不同的是，暖通空调过滤器的使用时间较长，可提供家庭中存在的空气悬浮颗粒物的完整样本，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的分析为评估家庭中颗粒结合污染物的空气浓度提供了新的机会。 拟议研究的中心目标既是通过比较详细的长期测试中的过滤器测量来探索这种创新抽样方法的有效性，也是通过从家庭中回收过滤器并分析其上的灰尘来探索这种方法在法医学背景下的实用性。将探索的特定污染物包括真菌、过敏原、黑炭和重金属。拟议方法的主要好处是通过了解我们暴露在严重污染物中来改善加拿大人的健康。拟议研究的另一个好处是开发了一种低成本的方法，用于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。这项研究将对室内颗粒结合污染物的浓度有一个革命性的理解。

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.