Sustainable Growth in Planned Communities

In the United States, the burden of disease increasingly involves chronic conditions like obesity, mental health disorders, and cardiovascular diseases—issues closely linked to our built environment. Urban development since the 1950s has drastically reshaped this environment, reducing green spaces, increasing traffic-related air pollution, and limiting opportunities for interaction with nature. These changes have contributed to a decline in public health, marked by rising rates of obesity, stress, and injuries, particularly in densely populated urban areas.

Master-planned communities (MPCs), especially those situated away from urban congestion, offer a healthier and more holistic living environment. Active adult lifestyle communities (AALCs), such as Tellico Village in rural Tennessee, exemplify this trend. These communities provide abundant green spaces, extensive hiking trails developed by retirees, and foster a strong sense of social connection, enhancing physical activity, mental well-being, and opportunities for community engagement. For retirees and those seeking better health outcomes, MPCs like these are increasingly appealing due to their integration of natural surroundings and communal support systems.

Poor living conditions are well-known risk factors for adverse health outcomes, while access to parks, green spaces, and blue spaces like lakes and rivers has been shown to reduce stress and decrease mortality during extreme heat events. Tellico Village’s proximity to a lake, woods and mountains showcases how the combination of green and blue spaces can create an environment that supports healthier living, promoting both physical activity and relaxation.

A recent paper on arXiv explores the growth patterns of MPCs using Tellico Village as a case study, highlighting how predictive modeling can guide sustainable development. As environmental health enters a critical phase, research will increasingly focus on integrating housing growth, microtransit, recreational activities, food services, and preventive health measures into MPCs to support healthier communities. AALCs provide social interaction, physical activity, and engagement opportunities that have been shown to positively influence cognitive function and delay the onset of neurodegenerative conditions. As these communities evolve, they hold potential to become integral to aging-in-place strategies, incorporating advancements in healthcare, smart home technologies, and brain health interventions.

Looking ahead, the planning and development of age-restricted communities must address the complex dynamics of aging populations. Advanced forecasting techniques, such as the Time-Varying Markov Models (TVMM) developed by Allsup and Gabashvili (2024), offer innovative approaches to anticipating the needs of these communities, particularly during transitions between growth phases. This method helps navigate the complexities of MPC development, ensuring that Active Adult Lifestyle Communities remain vibrant and supportive environments for older adults.

The study by Allsup and Gabashvili marks a significant advancement in understanding MPC growth dynamics. By focusing on micro-level interactions and decision-making, the research introduces a data-driven approach that reflects the real-world behaviors within these communities. This granular perspective enriches our understanding of MPC development and enhances the precision of future forecasting models, guiding strategic planning.

Moreover, this study is groundbreaking in its use of extensive data from state and local MPC authorities, setting a precedent for future research and planning. As age-restricted communities continue to evolve, these insights underscore the potential for integrating healthcare advancements, smart technologies, and targeted brain health interventions, positioning MPCs at the forefront of aging-in-place strategies.

This juncture represents a transformative moment in reimagining how we design living spaces that prioritize health, sustainability, and well-being, paving the way for communities that enhance the quality of life for older adults in a rapidly changing world.

REFERENCE

Allsup C.K., Gabashvili I.S. Modeling the Dynamics of Growth in Master-Planned Communities August, 2024 arXiv:2408.14214 [econ.EM] https://doi.org/10.48550/arXiv.2408.14214

Life Exposures and Health

In our daily lives, we are exposed to thousands of substances, yet the impact of many of these chemicals on our health remains unclear. This gap in knowledge is what the Southern Environmental Health Study (SEHS) aims to address. By finding connections between life exposures and health, this study seeks to improve the well-being of all communities. Adults between the ages of 40 and 70 who live in southern states are invited to join this critical research effort. Compensation is provided for participation.

The SEHS is enlisting volunteers to wear specialized wristbands for seven days. These wristbands, designed to absorb a variety of chemicals, provide insight into the substances individuals encounter in their environment and those emanating from their bodies. By participating, you will help to map out the spectrum of chemical exposure over a week, offering a unique window into the interactions with our surroundings.

The wristbands used in this study are equipped with advanced materials capable of absorbing a wide range of chemicals, including:

Polycyclic Aromatic Hydrocarbons (PAHs)

Organophosphate Esters (OPEs)

Pesticides

Plasticizers including Phthalates

Flame Retardants (FRs) 

Polychlorinated Biphenyls (PCBs) and Brominated Flame Retardants (BFRs), including PBDEs (Polybrominated diphenyl ethers)

Nicotine and Cotinine

Phenols

VOCs including Carboxylic Acids, Alcohols, Ketones, Sulfur- and Nitrogen-containing compounds

The wristbands operate through a process known as solid-phase microextraction (SPME), where the material absorbs chemicals directly from the environment and from sweat. These absorbed chemicals are then analyzed using Gas Chromatography-Mass Spectrometry (GC-MS), allowing for the identification and quantification of a wide range of compounds. 

Traditional wristbands can accumulate a wide range of volatile organic compounds (VOCs), but not all materials have a high affinity for molecules like trimethylamine (TMA). TMA is more difficult to be captured due to their high polarity and poor extraction efficiency. One approach to capture these molecules is solid-phase microextraction (SPME), which couples with triple quadrupole gas chromatography tandem mass spectrometry. Previous research on SPME of SCFAs demonstrated poor extraction efficiency, necessitating on-fiber derivatization to enhance detection sensitivity. To improve the capture of molecules like TMA, pre-coating the wristband material with reagents that react with TMA to convert it into a less polar and more easily extractable compound could be employed. Common reagents include pentafluorobenzaldehyde (PFB) or o-phthalaldehyde (OPA). Using materials like ion-exchange resins or functionalized polymers with a high affinity for polar compounds or higher surface area for adsorption would also help. Even with traditional materials, optimized solvent extraction or multi-step extraction processes could improve capture efficiency.

For this study you will be asked to wear a wristband. In the past, participants also wore samplers on their ankles, chest, and shoes. Shoe samplers were more sensitive to particle-bound semi volatile compounds (SVOCs), while chest samplers collected more exhaled compounds. Many chemicals displayed seasonal fluctuations. 

The longer the wristband is worn, the more chemicals accumulate on it.  The wristbands absorb chemicals at a rate proportional to the environmental concentration of these chemicals over time, effectively sampling the environment in a first-order kinetic manner.

To join, click this link. 

Eligibility: Adults ages 40-70 living in Alabama, Arkansas, Delaware, District of Columbia, Florida, Georgia, Kentucky, Louisiana, Maryland, Mississippi, Missouri, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Virginia, West Virginia.

REFERENCES

Fuentes ZC, Schwartz YL, Robuck AR, Walker DI. Operationalizing the Exposome Using Passive Silicone Samplers. Curr Pollut Rep. 2022;8(1):1-29. doi: 10.1007/s40726-021-00211-6. Epub 2022 Jan 4. PMID: 35004129; PMCID: PMC8724229.

Roodt AP, Naudé Y, Stoltz A, Rohwer E. Human skin volatiles: Passive sampling and GC × GC-ToFMS analysis as a tool to investigate the skin microbiome and interactions with anthropophilic mosquito disease vectors. J Chromatogr B Analyt Technol Biomed Life Sci. 2018 Oct 15;1097-1098:83-93. doi: 10.1016/j.jchromb.2018.09.002. Epub 2018 Sep 3. PMID: 30212730

The Ubiquitous Journey of Propylene Oxide

While Propylene Oxide (PO) may not be as infamous as some chemicals, its widespread use in industrial and consumer applications has made it a constant presence in our environment. Industries that rely on PO include those producing polyurethane polyols, propylene glycol, and fumigants.

The global market for Propylene Oxide estimated at $14.4 billion in 2020, is projected to reach $18.8 billion by 2027. Additionally, traffic emissions contribute to ambient levels of propylene, the precursor of PO, further underscoring its ubiquitous nature.

Recent research has revealed that many chemicals, including PO, leave more significant marks on the human body than previously thought. A new study by the Environmental Working Group (EWG) found chlormequat, a lesser-known pesticide, in 80% of people tested. Chlormequat chloride, used increasingly on grain crops in North America, has been linked to reduced fertility and developmental harm at doses lower than regulatory agencies' allowable daily intake levels. The study reported a significant increase in chlormequat concentrations in urine samples collected in 2023 compared to previous years.

A recent systematic review published on MedrXiv, titled "Biological Factors Influencing Individual Responses to Propylene Oxide," sheds light on the complex interplay between environmental exposures, genetic makeup, and individual susceptibility concerning PO levels in the human body. This review highlights the growing public health significance of propylene oxide beyond occupational exposure.

The study emphasizes the importance of considering individual variability in response to PO exposure, influenced by factors such as sex, dietary preferences, genetics, and physiology. It focuses on several genes (CYPs, mEH, GSTT1, GSTM1, FMO3, ADH, ALDH, GDHt) and microbes (including opportunistic pathogens, neutral or even beneficial bacteria) that could be relevant to PO metabolism reactivation and elimination from the body.

PO, primarily encountered through inhalation in occupational settings, poses potential health risks due to its genotoxic effects on DNA. The metabolism of PO primarily occurs through glutathione conjugation and epoxide hydrolase-mediated hydration, with interspecies differences noted. Furthermore, the human microbiome's role in PO metabolism highlights the complexity of individual responses, while environmental factors and seasonal variations further modulate PO's impact.

This comprehensive review stresses the limitations in our abilities to maintain and continuously update living reviews and indexing. It also emphasizes the importance of advancing AI capabilities in literature reviews to capture nuanced, indirect evidence more effectively. While AI tools like Elicit and Perplexity show promise, challenges persist in processing longer segments of information and ensuring consistency across platforms.

Moving forward, the development of specialized AI architectures tailored for systematic reviews is imperative. By enhancing AI tools strategically, we can navigate the complexities of scientific literature more effectively, enabling better summarization and addressing unanswered questions in environmental health research. This study paves the way for targeted research and technological innovation, advocating for a multidisciplinary approach to understanding individual responses to environmental chemicals like PO.

REFERENCES

Gabashvili, IS. Biological Factors Influencing Individual Responses to Propylene Oxide: A Systematic Review medRxiv 2024.02.15.24302622; doi: https://doi.org/10.1101/2024.02.15.24302622

Temkin, A.M., Evans, S., Spyropoulos, D.D. et al. A pilot study of chlormequat in food and urine from adults in the United States from 2017 to 2023. J Expo Sci Environ Epidemiol (2024). https://doi.org/10.1038/s41370-024-00643-4

Open-Source Project: OSF | Biological Factors that Influence Individual Responses to Environmental Epoxides DOI 10.17605/OSF.IO/W7682