Beyond the Flames: Exploring the Impact of Wildfires on Watershed Health and Air Purity

In the blaze of a wildfire, ecosystems are transformed. Wildlife scrambles for safety as the flames rip across the landscape and vegetation is reduced to ash. Under the intense heat, soil characteristics shift toward greater hydrophobicity, and the air rises with smoke. In the smoldering stillness that follows, ecologists, analytical chemists, and public health officials are left to solve important questions regarding human and ecological health: what is the extent of the ecosystem damage, and how long will the effects last?

Image Credit: Alaskagirl8821/Shutterstock.com

High-elevation forest watersheds have drawn the attention of many concerned. These regions, critical for ensuring the health of ecosystems and regulating water flow to human communities, are predicted to experience an increase in wildfires owing to global warming. By studying the impact of wildfires on these slow-to-recover areas, researchers can better understand the effects of wildfires on the water supply.¹

One example involves the four major wildfires that spread across the Continental Divide in Colorado and southern Wyoming in 2020. These fires were some of the largest on record, burning catchments that provided water to industrial, agricultural, and residential communities. In the aftermath, run-off enriched with nitrogen and phosphorous migrated into headwater tributaries, affecting storage reservoirs and water utilities.

In the second post-fire year, researchers found water quality reflecting the range of severely burned land, as nitrate concentrations in water storage reservoirs spiked during the spring snowmelt. Transporting nutrients from burned soils into neighboring waterbodies also contributed to algal blooms, further damaging the ecosystem.²

As wildfires are predicted to increase worldwide, there has never been a better time to understand their impact. Enter Pittcon, an annual conference and exposition that provides a platform for scientists, researchers, and professionals in analytical chemistry and applied spectroscopy.

This February, Pittcon presents its Environment & Energy track, inviting experts to delve into the latest advancements, share insights, and collectively work toward a comprehensive understanding of the far-reaching impact of wildfires. To find out more, visit Pittcon.org.

Air Quality Effects of Wildland Urban Interface Fires

In the last 40 years, the margins of urbanization and wildland vegetation have begun to blur at an unprecedented rate. Around the world, the expansion of these wildland-urban interfaces (WUIs) has tracked an uptick in the urban development of the former wilderness and the migration of people from the countryside to cities.

While some may argue that these hybrid environments bring together the best of both worlds, WUIs pose significant fire hazards, including an elevated risk of rapid fire spread, intensified fire behavior, and challenges in access and evacuation. This has led to a series of disasters, such as the 2009 Victoria bushfires, the 2017 wildfires in Portugal, and the 2018 Camp Fire in Northern California.^3,4

WUI fires bring added complexity—air pollution. Fires at the fringe of land and leaves burn biomass, buildings, and vehicles. Synthetic materials such as plastics, metals, and chemicals are aerosolized and brought into proximity with dense population centers.

The effects on human health are yet to be understood, but urban fires indicate a dizzying cocktail of toxic emissions, including inorganic gases, isocyanates, organic compounds, dioxins and furans, and metals.⁵

This year, Pittcon is helping to unravel the intricacies of WUI wildfire emissions by providing an environment for the application of advanced analytical techniques, such as gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS). Bringing together professionals from government, industry, and academia, this conference fosters collaborative efforts across disciplines, aiming to apply these sophisticated methods for pinpointing contaminants across regions impacted by wildfires.

From Flames to Formulas: A Symposium on the Environmental Chemistry of Fire

On February 26^th, Pittcon will feature a symposium by Dr Charles “Chuck” Rhoades, entitled: The Environmental Chemistry of Fire: Methods, Instruments, and Analytical Results (Thurman). This talk will discuss how downstream consequences of wildfires reflect the extent and severity of a burned watershed.

As a research chemist at the Rocky Mountain Research Station, Dr Rhoades’s experience will add both color and gravity to the symposium. His current research examines the biogeochemical interactions between terrestrial and aquatic ecosystems in controlled and natural settings and has led to significant findings, such as soil changes in burn scars, which do not appear to be a significant barrier to tree colonization.^6,7

Looking at increasing wildfires on this planet, this symposium cannot be missed—ensure you include this event in your Pittcon 2024 schedule.

In the Fire's Wake: Symposia on Detecting and Measuring Fire Emissions

Various analytical techniques have come to the forefront in the search to understand the composition of wildfire emissions.

GC-MS and LC-MS can meticulously separate and identify volatile organic compounds (VOCs) based on their distinct chemical properties. For real-time detection of VOCs, Proton Transfer Reaction Time-of-Flight Mass Spectrometric (PTR-TOF-MS), Selected Ion Flow Tube Mass Spectrometry (SIFT-MS), and CI-ToF-MS are validated methods.^8,9,10,11

A deeper dive into the application of CI-ToF-MS for detecting VOCs produced by wildfires can be found at Pittcon 2024. Following the talk by Dr Rhoades, Pittcon will showcase a symposium by Dr Abigail Koss, entitled: Solving the chemical mysteries of smoke: application of chemical ionization time-of-flight mass spectrometry for wildfire studies.

In this talk, Dr Koss will present multiple case studies where CI-TOF-MS has been effectively utilized across different wildfire scenarios, emphasizing the instrument's proficiency in distinguishing distinct marker compounds associated with various forms of biomass burning, and discussing how they react in the atmosphere.

Following the talk by Dr Koss, a third symposium will be held expounding WUI fire emissions and the challenges in measuring these compounds. This talk is presented by Dr Amara Holder, Mechanical Engineer at the US EPA, entitled: The Chemistry of Fires in the Wildland Urban Interface. With awards including the EPA Office of Research and Development Bronze Medal Award and the ORD Bronze Award for her Black Carbon Sensor Team role, Dr Holder is well placed to share her expertise on fire emissions.¹²

Wildfire Technology at Pittcon 

This year, Pittcon will also host Beijing Huironghe Technology Co., Ltd., which will present state-of-the-art solutions for tackling the complexities associated with wildfire emissions and their environmental consequences. From aerosol mass concentration detectors to VOC gas quantitative generators, Beijing Huironghe Technology Co., Ltd. will exhibit cutting-edge instruments at the forefront of analytical advancements in wildfire research.

Pittcon 2024 Illuminates Wildfire Impacts and Analytical Progress

As wildfires become increasingly frequent and intense globally, we must better understand their wide-reaching effects on watersheds, air quality, and ecosystems.

The Environment & Energy track at Pittcon 2024 serves as a forum, bringing together experts from various fields to exchange knowledge in analytical chemistry. The symposia session on February 26^th will shed light on vital aspects of wildfires, providing valuable perspectives and potential solutions for the future. To learn more, visit Pittcon.org.

References and Further Reading

1. Loehman, R.A., et al. (2011). Modeling Climate Changes and Wildfire Interactions: Effects on Whitebark Pine (Pinus albicaulis) and Implications for Restoration, Glacier National Park, Montana, USA. USDA Forest Service Proceedings.
2. Rhoades, C., et al. (2022). Soil and Water Connections after Colorado’s Largest Wildfire. ASA, CSSA, SSSA International Annual Meeting, Baltimore, MD. Available at: https://scisoc.confex.com/scisoc/2022am/meetingapp.cgi/Paper/144974 (Accessed on 01 January 2024).
3. Defossé, G. (2023). Editorial: Fires in the wildland urban interface: An emerging global phenomenon threatening modern society. Frontiers in Forests and Global Change. doi.org/10.3389/ffgc.2023.1137014
4. Nunes, A.N., et al. (2023). Assessing Wildfire Hazard in the Wildland–Urban Interfaces (WUIs) of Central Portugal. Forests. doi.org/10.3390/f14061106
5. Holder, A.L., et al. (2023). Hazardous air pollutant emissions estimates from wildfires in the wildland urban interface. PNAS Nexus. doi.org/10.1093/pnasnexus/pgad186
6. USDA Forest Service: U.S. Department of Agriculture. Charles C. Rhoades. Available at: https://www.fs.usda.gov/research/about/people/crhoades#research-tab (Accessed on 01 January 2024).
7. Rhoades, C., et al. (2019). The Legacy of a Severe Wildfire on Stream Nitrogen and Carbon in Headwater Catchments. Ecosystems. doi.org/10.1007/s10021-018-0293-6
8. Peeters, K., et al. (2020). Review: The Use of Bench-Scale Tests to Determine Toxic Organic Compounds in Fire Effluents and to Subsequently Estimate Their Impact on the Environment. Fire Technology. doi.org/10.1007/s10694-020-01065-y
9. Brilli, F., et al. (2014). Proton Transfer Reaction Time-of-Flight Mass Spectrometric (PTR-TOF-MS) determination of volatile organic compounds (VOCs) emitted from a biomass fire developed under stable nocturnal conditions. Atmospheric Environment. doi.org/10.1016/j.atmosenv.2014.08.007
10. Guérette, E., et al. (2018). Emissions of trace gases from Australian temperate forest fires: emission factors and dependence on modified combustion efficiency. Atmospheric Chemistry and Physics. doi.org/10.5194/acp-18-3717-2018
11. Hutterli, M.A., et al. (2022). Time-Of-Flight Mass Spectrometers Made in Switzerland: Examples of Mobile Applications. CHIMIA. doi.org/10.2533/chimia.2022.60
12. EPA. Amara Holder, Mechanical Engineer in EPA's National Risk Management Research Laboratory. Available at: https://www.epa.gov/sites/default/files/2019-03/documents/holderamara_biosketche_aemd.pdf

This information has been sourced, reviewed and adapted from materials provided by Pittcon.

For more information on this source, please visit Pittcon.