There is a part of my brain that is continuously asking how things work. It’s an indiscriminate process that leads me to ask questions as different as “How does the Higgs field work?” and “Why do egg whites turn into meringue?” So, even though at first glance the subject of lunar soil is far from my genetics expertise, when I heard about the RIS4E project I was curious to know how lunar soil interacts with human bodies.
If we hope to return humans to the Moon for long-term exploration and science, the effects of exposure to lunar dust need to be considered. Typically on Earth, we do not consider breathing in dust to be dangerous, with some notable exceptions such as asbestos and coal. On the Moon, however, the dust has different properties that make it potentially dangerous. The lunar dust consists of sharp particles that include individual mineral grains and glass, some of which have a thin rind that includes submicroscopic particles of metallic iron. This combination makes the dust both physically abrasive and chemically reactive. After a few months’ exposure, we might expect to see sustained lung inflammation or other respiratory disorders develop. However, as harmful as these symptoms would be, there are further consequences to be considered.
Lunar dust may have the capacity to damage DNA. The human body is equipped with DNA repair systems that, under normal circumstances, keep DNA damage to a minimum. However, under conditions of genotoxic stress, the DNA can become damaged faster than it can be repaired. Unrepaired DNA damage leads to mutations in the DNA after replication. Mutations can lead to outcomes of varying severity, such as enabling cancerous growth or causing age-related neurodegenerative disorders such as Parkinson’s and Alzheimer’s diseases. It is important to note that these are health issues that would not arise until months or years after the astronauts have returned to Earth.
The purpose of my research as a RIS4E graduate student in the Department of Pharmacological Sciences at Stony Brook University is to investigate the DNA damage potential of lunar dust. Since actual samples of lunar dust are a precious resource, we will start out by using simulants to model the effects of lunar dust. Most of the simulants are derived from volcanic ash and are physically similar to actual lunar dust. Various concentrations of the simulants will be used to treat cells in culture, and the impact on their DNA molecules will be assessed using sophisticated molecular methods to define the types of damage. Observing DNA damage after treating cells with the simulants would imply that lunar dust has the potential to cause DNA damage. If this is the case, then NASA’s Human Exploration and Operations Mission Directorate will have to take the necessary precautions to mitigate the danger to astronauts posed by the inhalation of lunar dust.