2025-06-02 ブラウン大学
＜関連情報＞
- https://www.brown.edu/news/2025-06-02/saltonsea
- https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024GH001327
富栄養化促進、硫化水素、環境不正： ソルトン・シーにおけるメカニズムと知識のギャップ Hypereutrophication, Hydrogen Sulfide, and Environmental Injustices: Mechanisms and Knowledge Gaps at the Salton Sea
Diego Centeno, Alejandra G. Lopez, Aydee Palomino, Juliana Taboada, Ryan Sinclair, Quinn Montgomery, Consuelo Marquez, Migdalia N. Sanchez, Isabella B. Arzeno-Soltero, Mara A. Freilich
GeoHealth Published: 31 May 2025
DOI:https://doi.org/10.1029/2024GH001327
Abstract
The Salton Sea, California’s largest lake, is undergoing significant environmental degradation, which has adverse health effects on nearby rural communities, primarily Latinx and Torres Martinez Desert Cahuilla Indian. Over the past two decades, the lake’s water levels have steadily dropped. Water conditions in the Sea, characterized by low oxygen and high nutrient levels, favor the production of hydrogen sulfide (H2S). This study investigates the connection between the Sea’s changing conditions, particularly the worsening water quality, and H2S emissions using air quality and water quality data collected since 2013 and 2004, respectively. H2S concentrations often exceed California’s air quality standards, particularly in areas near the Sea during summer months. Wind patterns substantially impact detection of H2S. When wind is blowing from the Sea toward communities with sensors, located to the northwest of the Sea, H2S is detected significantly more often. Current monitoring efforts underestimate the frequency and distribution of H2S that exceeds air quality standards. An air sensor deployed in shallow water over the Salton Sea by a community science program detected substantially higher concentrations of H2S, particularly when wind was blowing over exposed sediment and shallow water, suggesting that these are a significant and overlooked H2S source at the Salton Sea. These findings highlight the need for improved air quality monitoring and more effective environmental management policies to protect public health in the region. The study emphasizes the importance of community-led solutions and provides insights relevant to other regions experiencing similar environmental crises.
Key Points
- The Salton Sea is a major source of elevated hydrogen sulfide emissions, with concentrations likely underestimated due to limited monitoring
- Sensor placement and wind direction are crucial in H2S monitoring, highlighting the distinction between measuring and detecting emissions
- Environmental justice concerns arise as vulnerable communities are chronically exposed to harmful H2S levels
Plain Language Summary
The Salton Sea is a heavily contaminated shrinking lake that affects the health of surrounding vulnerable communities in the Coachella and Imperial Valleys. Due to high-nutrient agricultural runoff entering the lake and resulting low oxygen levels, the lake often emits hydrogen sulfide (H2S), a harmful gas. The study aims to understand what causes H2S emissions with the aim of predicting and reducing emissions. Using data collected over the past two decades, the connection between water conditions, air quality, and wind patterns was examined to understand when and where harmful H2S levels occur. During the study period, H2S concentrations near the Salton Sea frequently exceed California’s air quality standards, especially during summer and when winds blow toward communities. Community-deployed sensors detected higher levels of H2S due to the placement within the sea and suggested emissions from exposed sediment and shallow water. However, current monitoring efforts underreport the scale of H2S impacts. These findings serve as evidence for the urgent need to improve air quality monitoring and policies to protect public health in the Salton Sea region. Community-led solutions as the ones employed in this study are critical for overcoming environmental injustices and serve as a framework for similar situations worldwide.
