EGU General Assembly 2022
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the Creative Commons Attribution 4.0 License.

The influence of atmospheric and cellular H2O2 on ROS concentrations and OH radical production in the lung

Eleni Dovrou, Steven Lelieveld, Ashmi Mishra, Ulrich Pöschl, and Thomas Berkemeier
Eleni Dovrou et al.
  • Multiphase Chemistry Department, Max Planck Institute for Chemistry, Mainz, Germany

Atmospheric pollution is a significant cause of oxidative stress in the human pulmonary system. (1–3) Fine particulate matter (PM2.5) has been linked to adverse health effects due to the size and composition of particulates. Gas-phase chemical species, such as ozone, have also been considered as significant pollutants posing threat to human health.(3-4) However, other reactive gas-phase species, such as peroxides, have hardly been examined.

The epithelial lining fluid (ELF) is a large interface between the atmosphere and human body.(5) Transition metals enter the ELF through inhalation of PM2.5 and play a key role in the potential occurrence of health effects. In the presence of transition metals, peroxides such as hydrogen peroxide (H2O2are converted into the highly reactive OH radical through Fenton chemistry. Due to its high reactivity, the OH radical is most likely to cause oxidative stress and Fenton chemistry is probably an important OH source in the lung.(6) High levels in both, peroxide and transition metal concentrations in the ELF, could thus have adverse health outcomes.

We investigate the role of the most abundant atmospheric peroxide, H2O2, in the formation of reactive oxygen species (ROS: H2O2, OH, O2-, HO2)(5) in the human body using a kinetic multilayer model. We find that, besides ambient concentrations, transport to and from lung cells and the circulatory system affects H2O2 levels in the ELF and, accordingly, exhaled breath condensate (EBC). The model predicts levels of H2O2 in EBC, lung cellular space, and blood, in agreement with the literature. The H2O2 concentration in the ELF, where measurements cannot be conducted easily, can be inferred from the model and used to estimate air pollution-induced ROS production in the human body. We present scenarios of atmospherically relevant conditions of H2O2 and PM2.5 pollution in urban and rural areas and simulate the effect of co-inhalation of H2O2 and PM2.5 on ROS production in the ELF. We discuss the hypothesis whether accumulation of H2O2, either by inhalation or in-body transport, may be a prerequisite for PM2.5 toxicity


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6. S. Lelieveld, et al., Hydroxyl Radical Production by Air Pollutants in Epithelial Lining Fluid Governed by Interconversion and Scavenging of Reactive Oxygen Species. Environ. Sci. Technol. 55, 14069-14079 (2021).

How to cite: Dovrou, E., Lelieveld, S., Mishra, A., Pöschl, U., and Berkemeier, T.: The influence of atmospheric and cellular H2O2 on ROS concentrations and OH radical production in the lung, EGU General Assembly 2022, Vienna, Austria, 23–27 May 2022, EGU22-8379,, 2022.