A recent study led by Dr. R. Li from the Key Laboratory of Geographic Information Science at East China Normal University has shed light on the distribution and sources of polycyclic aromatic hydrocarbons (PAHs) and their derivatives in the global marine atmosphere. The research, published in the journal Atmospheric Chemistry and Physics, offers valuable insights for maritime professionals, particularly in understanding air quality and potential health impacts.
PAHs are a group of chemicals that are known to have severe adverse effects on both human health and marine ecosystems. They are primarily released into the atmosphere through incomplete combustion of organic materials, such as coal, wood, and oil. The study collected high-volume air samples along a transect from China to Antarctica, providing a comprehensive overview of PAH concentrations and sources in various marine regions.
The highest PAH concentrations were observed in the Western Pacific, with an average of 447 picograms per cubic meter (pg/m³), followed by the East China Sea (195 pg/m³). Surprisingly, the Antarctic Ocean had higher PAH levels (111 pg/m³) than the East Australian Sea (104 pg/m³) and the Bismarck Sea (17 pg/m³). Dr. Li noted, “This could be attributed to the relatively low anthropogenic PAH emissions from Australia and Papua New Guinea, whereas the Antarctic Ocean is often affected by emissions from engine combustion and biomass burning.”
The study also found that oxygenated PAHs (OPAHs) were more prevalent in the East Australian Sea due to secondary formation processes. “OPAHs mainly originated from the secondary formation of parent PAHs through reactions with ozone and hydroxyl radicals, both of which are more prevalent in the East Australian Sea,” explained Dr. Li.
The research identified three primary sources of PAHs and their derivatives in marine aerosols: coal burning and engine combustion emissions (56%), wood and biomass burning (30%), and secondary formation (14%). These findings have significant implications for the maritime industry, particularly in terms of air quality management and regulatory compliance.
For shipping companies, understanding the sources and distribution of PAHs can help in developing strategies to reduce emissions and mitigate health risks for crew members. Port authorities can also use this information to implement better air quality monitoring and control measures. Additionally, the study highlights the importance of considering both local and long-range sources of pollution, which can impact marine environments far from their origin.
Dr. Li’s research underscores the need for continued monitoring and regulation of PAH emissions in the maritime sector. As the industry strives to meet increasingly stringent environmental standards, insights from this study can guide the development of more effective and targeted pollution control measures.
In summary, the study provides a crucial foundation for understanding the sources and distribution of PAHs in the marine atmosphere. For maritime professionals, this research offers valuable data to inform decision-making and improve air quality management practices. As Dr. Li’s work demonstrates, addressing PAH pollution requires a comprehensive approach that considers both local and global sources, as well as the complex chemical processes that transform these pollutants in the atmosphere.