20 March 2025 – Bangkok, Thailand

The Network Center for the EANET organized a virtual workshop on the Emission Inventory of Volatile Organic Compounds (VOCs) and its Application for Policy Consideration on December 4, 2024. The workshop consisted of two sessions: expert lectures and participant presentations. The first session covered key topics such as the importance of developing an emission inventory for atmospheric environmental management, methodologies to estimate VOCs’ emissions from stationary sources, the transportation sector, and biogenic sources. It also included air quality modeling of VOCs and control measures for VOCs. Participants shared the status of VOCs management in their respective countries and discussed ideas for EANET’s involvement in addressing VOCs’ issues. Approximately 60 participants attended the workshop.

.

Exploring Emission Inventory Methodologies and Applications: Insights from Experts

Dr. Jun-ichi Kurokawa, from the Asia Center for Air Pollution Research serving as the Network Center for the EANET, delivered a lecture on the introduction of emission inventories, focusing on their roles in managing atmospheric environmental issues and the basic methodology to develop an emission inventory, particularly for Volatile Organic Compounds (VOCs) emissions from stationary sources. The presentation began by highlighting the necessity and framework of air quality management, emphasizing the importance of VOCs and emission inventories. For methodologies, general procedures to develop emission inventories were explained, following the process flow of the development from defining the scope and structure to create emission tables and gridded data. Next, the methodology for estimating VOCs emissions from stationary sources was presented. This included details of sector categories, examples of fugitive emissions characteristics of VOCs sources, collecting and setting activity data, emission factors, removal efficiencies, speciation to components, and calculating emissions to create final products. References for methodologies to develop emission inventories were also introduced.

Dr. Tazuko Morikawa from the Japan Automobile Research Institute delivered a lecture on the methodology for estimating emissions from road transport. The lecture began with an overview of global changes in passenger cars and heavy duty vehicles, including electrification targets for passenger cars aimed at mitigating both climate change and air pollution. Next, the necessary information for developing emission inventories for the road transport sector was detailed. This included characteristics of gasoline and diesel vehicles, methods for calculating tail pipe emissions, the definition and estimation of evaporative emission from gasoline vehicles (which are particularly important for VOCs), and component species of VOCs in emissions from the road transport sector. Finally, bioethanol-blended fuels originally introduced to mitigate climate change were discussed due to their impact on air pollutants emissions.

.

.

Dr. Justin Sentian, from Universiti Malaysia Sabah, Malaysia, delivered a lecture on VOCs emissions from biogenic sources. Biogenic VOCs (BVOCs) are organic compounds emitted by plants and other biological sources. Although these are natural sources, the importance of BVOCs was highlighted due to their strong impact on the formation of ozone and secondary PM_2.5. Understanding the contribution of BVOCs is essential for developing effective policies to control anthropogenic VOCs emissions. The lecture also covered the recent status of BVOCs emissions and case studies for Southeast Asia, including future simulations under different climate scenarios. Since BVOCs emissions are significantly influenced by temperature, climate change impacts BVOCs emissions, which in turn affects ozone and PM_2.5 concentrations.

Dr. Satoru Chatani from the National Institute for Environmental Studies presented a lecture on the air quality modeling of anthropogenic VOCs. The lecture began by introducing the necessities and roles of air quality simulations for VOCs, which help understand complex physical and chemical processes, including non-linear relationships among NO_x, VOCs, and ozone. Next, the treatment of VOCs and their photochemical reactions was explained, including popular chemical modules and VOCs speciation used in air quality models. Application methodologies of air quality models to analyze VOCs issues were then introduced, covering validations and evaluations of simulated results based on monitoring data. This highlighted the importance of monitoring of VOCs and their components. It was emphasized that air quality modeling is essential for developing effective strategies to suppress ambient concentrations of secondary pollutants.

Dr. Shinichi Yonemochi from the Center for Environmental Science in Saitama delivered a lecture on control measures of VOCs using the case of Saitama Prefecture of Japan. The lecture began with an overview of the current and historical backgrounds of Saitama Prefecture focusing on the status of ozone pollution. Regulations of VOCs in Saitama Prefecture, including legal measures and voluntary actions by companies to reduce VOCs were explained.

Next, trends in VOCs emissions from major sources in Saitama Prefecture were presented to demonstrate the effects of these regulations. Examples of actual control measures were introduced, includingVOCs’ emission control techniques, VOC measuring instruments, and experiences using them in various applications such as for outdoor painting and the cleaning process for printing machines.

 .

Addressing the Status and Issues of VOCs: Perspectives from Participants

During the second session, participants exchanged information on VOCs related issues in their countries, including the general status of air quality, specific topics such as the management of the petrochemical industry, and the progress and challenges in developing VOCs emission inventories. As in previous workshops, many countries identified the continuous enhancement of national emission inventories as a challenge and expressed the desire for additional EANET projects focusing on capacity-building activities. Suggestions included not only webinars but also on-site training courses for major source categories of the emission inventory. The Network Center for the EANET, as the workshop organizer, will assess potential future activities through the EANET Project Fund.

.

Find out more about the EANET Project Fund.

.

Useful Resources

• Outline and Program
• Panelists and Participants’ Presentations:
  • Introduction of Emission Inventory and VOCs Emissions From Stationary Sources (by Dr. Jun-ichi Kurokawa)
  • VOCs Emissions from Road Transport (by Dr. Tazuko Morikawa)
  • NMVOCs Emissions from Biogenic Sources (by Dr. Justin Sentian)
  • Air Quality Modeling of NMVOCs (by Dr. Satoru Chatani)
  • Control Measures of VOCs: Case Study of Saitama Prefecture of Japan (by Dr. Shinichi Yonemochi)
  • Presentations from Participants

.

Photo credits: aerial photography of interlocking freeways with travelling cars by Ed 259 free of copyrights (2017); other pictures: all rights reserved to EANET.