The impact of indoor air quality on respiratory health of older people living in nursing homes: spirometric and exhaled breath condensate assessments

Issue 2 - "Update on adverse respiratory effects of indoor air pollution" Part 1): Indoor air pollution and respiratory diseases: A general update and a Portuguese perspective

OBJECTIVE

To quantify the impact of different air pollutants on respiratory health based on robust estimates based on international data and to summarise the evidence of associations between indoor exposure to those pollutants and respiratory morbidity in the Portuguese population.

RESULTS

Several systematic reviews and meta-analyses (MA) at the world level demonstrate the impact of indoor air quality on respiratory health, with indoor particulate matter and gasses exerting a significant effect on the airways. Volatile organic compounds (VOC) have been related to asthma and lung cancer. However, only meta-analyses on biomass use allowed documentation of long-term respiratory effects. While early publications concerning Portuguese-based populations mainly focused on indoor exposure to environmental tobacco smoke, later studies relocated the attention to relevant exposure environments, such as day care buildings, schools, residences and nursing homes. Looking at the pooled effects from the reviewed studies, high levels of carbon dioxide and particulate matter in Portuguese buildings were significantly associated with asthma and wheezing, with VOC and fungi showing a similar effect in some instances.

CONCLUSIONS

Despite the significant reduction of indoor air pollution effects after the 2008 indoor smoking prohibition in public buildings, studies show that several indoor air parameters are still significantly associated with respiratory health in Portugal. The country shares the worldwide necessity of standardisation of methods and contextual data to increase the reach of epidemiological studies on household air pollution, allowing a weighted evaluation of interventions and policies focused on reducing the associated respiratory morbidity.

Nursing Home Adoption of CDC and ASHRAE COVID-19 Built Environment Recommendations: A Characterization Study of Colorado Nursing Home Facilities

BACKGROUND

During the COVID-19 pandemic, the Centers for Disease Control and Prevention (CDC) and ASHRAE provided infection control recommendations for the built environments and ventilation systems of nursing homes (NHs). The level of adoption of the suggested strategies is unknown, as little information has been obtained from NHs identifying the strategies that were implemented.

OBJECTIVE

The primary goal of our study was to characterize the built environments of Colorado NHs during the COVID-19 pandemic to assess the level of adoption of CDC and ASHRAE recommendations. Our secondary goal was to identify opportunities and barriers that NHs face as they work to create health-protective built environments in the future.

METHOD

We used the Nursing Home Built Environment survey to obtain data related to three main categories of CDC and ASHRAE recommendation for Colorado NHs: Resident Isolation, Improved Indoor Air Quality, and Staff Separation/Support.

RESULTS

Key findings included: (1) On average, NHs had 34% of their beds located in single-occupancy rooms; (2) seven (9%) NHs had designated COVID-positive "neighborhoods"; (3) 14 (20%) NHs had common area ventilation systems that were utilizing filters with a minimum efficiency reporting value 13 rating, or higher.

CONCLUSION

Most Colorado NHs did not fully implement the COVID-19 built environment strategies recommended by CDC and ASHRAE. While there are barriers to the adoption of many of the strategies, there are also opportunities for immediate improvements that can support the health of vulnerable NH populations as we continue to see high rates of aerosolized infectious disease spread in NH facilities.

Indoor Air Quality in Elderly Centers: Pollutants Emission and Health Effects

The world population is ageing, in particular in the developed world, with a significant increase in the percentage of people above 60 years old. They represent a segment of the population that is more vulnerable to adverse environmental conditions. Among them, indoor air quality is one of the most relevant, as elders spend comparatively more time indoors than younger generations. Furthermore, the recent COVID-19 pandemic contributed immensely to raising awareness of the importance of breathing air quality for human health and of the fact that indoor air is a vector for airborne infections and poisoning. Hence, this work reviews the state of the art regarding indoor air quality in elderly centers, considering the type of pollutants involved, their emission sources, and their health effects. Moreover, the influence of ventilation on air quality is also addressed. Notwithstanding the potential health problems with the corresponding costs and morbidity effects, only a few studies have considered explicitly indoor air quality and its impacts on elderly health. More studies are, therefore, necessary to objectively identify what are the impacts on the health of elderly people due to the quality of indoor air and how it can be improved, either by reducing the pollutants emission sources or by more adequate ventilation and thermal comfort strategies.

Determination of the key parameters of VOCs emitted from multi-layer leather furniture using a region traversal approach

Volatile organic compounds (VOCs) emitted from indoor materials and products are one of the main factors affecting air quality and human health. Compared with building materials and wooden furniture, leather furniture has a more complex internal structure and uneven emission surfaces. The market share of leather furniture is relatively high, while investigation on this kind of furniture is relatively rare. In this study, we develop a region traversal method to measure the three key parameters of VOC emissions from typical two-layer leather furniture, i.e., the initial emittable concentration, the diffusion coefficient, and the partition coefficient. A series of experiments examining VOC emissions from a leather sofa under different conditions, were carried out in a 1 m³ chamber. This method locks the upper and lower limits of an optimal solution through loop calculation in parameter intervals, and demonstrates high accuracy, efficiency and robustness. The good agreement (R² > 0.95) between model predictions and experimental data confirms the reliability of this method. In addition, the influence of temperature and air exchange rate on the key parameters is explored. Results indicate that, increasing the temperature leads to an increase in D_m and a decrease in K, and that air exchange rate does not affect the key parameters, which is consistent with physical principles. The region traversal method is further applied to analyze the emission scenarios for other furniture, which is very helpful for indoor air quality pre-evaluation.

Adequate indoor air quality in nursing homes: An unmet medical need

A small but growing body of literature indicates that concentrations of indoor particulate and gaseous pollutants in long-term care facilities (i.e., skilled nursing facilities) for older adults, hereafter referred to nursing homes, often exceed those recorded in nearby, comparable outdoor environments. Unlike the outdoors, indoor air quality (IAQ) in nursing homes is not regulated by legislation and is seldom monitored. To that end, residents of nursing homes commonly spend the vast majority of their time indoors where they are exposed to indoor air pollutants for long periods of time. Given that many nursing home residents, especially those of advanced age, are more susceptible to the effects of air pollutants, even at low concentrations, this prolonged exposure may adversely affect their health, well-being, quality of life and increase medical expenditures due to frequent, unscheduled acute care visits and hospitalizations. We propose an action plan for assessing IAQ in nursing homes, understanding the impacts of IAQ on adverse health outcomes of nursing home residents, and addressing vulnerabilities in these facilities to safeguard health, well-being, and quality of life of nursing home residents and minimizing unscheduled acute care visits and hospitalizations. We propose that IAQ should be regularly monitored in nursing homes to proactively identify and address vulnerabilities in these facilities and that resources should be provided for remedial interventions to improve IAQ in nursing homes, including but not limited to source control, improving ventilation and filtration, and deploying air cleaners where appropriate. This proactive approach may pave the way for establishing enforceable standards for indoor air quality in nursing homes that will promote health, well-being, and quality of life of nursing home residents and reduce medical expenditures.

Predicting the emission characteristics of VOCs in a simulated vehicle cabin environment based on small-scale chamber tests: Parameter determination and validation

Volatile organic compounds (VOCs) emitted from vehicle parts and interior materials can seriously affect in-cabin air quality. Prior studies mainly focused on indoor material emissions, while studies of emissions in-cabins were relatively scarce. The emission behaviors of VOCs from vehicle cabin materials can be characterized by three key emission parameters: the initial emittable concentration (C₀), diffusion coefficient (D_m), and partition coefficient (K). Based on a C-history method, we have performed a series of tests with a 30 L small-scale chamber to determine these three key emission parameters for six VOCs, benzene, toluene, ethylbenzene, xylene, formaldehyde, and acetaldehyde, from typical vehicle cabin materials, car roof upholstery, carpet, and seat. We found that acetaldehyde had the highest level in the gas-phase concentration and C₀, which differs from residential indoor environments where formaldehyde is usually the most prevalent pollutant. The influence of temperature on the key emission parameters was also investigated. When the temperature rose from 25 °C to 65 °C, C₀ increased by 40-640%, D_m increased by 40-170%, but K decreased by 38-71% for different material-VOC combinations. We then performed an independent validation to demonstrate the accuracy of the measured key emission parameters. Furthermore, considering that in reality, several materials coexist in vehicle cabins, we made a first attempt at applying a multi-source model to predict VOC emission behaviors in a simulated 3 m³ vehicle cabin, using the key emission parameters obtained from the small-scale chamber tests. The good agreement between the predictions and experiments (R² = 0.82-0.99) demonstrated that the three key emission parameters measured via chamber tests can be scaled to estimate emission scenarios in realistic vehicle cabin environments. A pollution contribution analysis for the tested materials indicated that the car seat could significantly contribute to the total emissions.