Harrison Schmitt, an astronaut of the Apollo 17 mission (1972), said that a kind of “lunar allergy” was brought as a souvenir of his trip to the terrestrial satellite , with sneezing, irritation of the throat and watery eyes, among other symptoms. The culprit was regolith, the name given to the fine and sharp powder like crushed crystal that covers the surface of the Moon.
Experiments with mice had already demonstrated the potential harmful effect of these tiny particles – with diameters of a thousandth of a meter – capable of infiltrating the respiratory tract and even the pulmonary alveoli, but a new study, published in the journal GeoHealth , expands the part of possible damage to the cells of the human body and its DNA. This would further complicate the possibility of sending astronauts there on lasting missions, as US President Donald Trump himself announced a few months ago.
Given the impossibility of setting up a laboratory on the Moon, scientists at the Stony Brooke University of Medicine, in New York, responsible for the experiment designed a substitute for regolith with terrestrial materials . To do this, they took into account that lunar dust, formed by meteorite impacts over billions of years, has very special characteristics, regardless of the size and consistency of its particles. With no protective atmosphere to act as a filter or something like a climate, the lunar surface is directly exposed to solar winds.
In addition, there are no organic compounds or compounds that include water , such as mica or clay, in the composition of the powder. It is an extremely dry material and, above all, with a significant electrostatic charge, to the point that the particles “levitate” on the ground . Hence, they adhere to any surface, machinery and spacesuits included, as the members of the manned Apollo missions between 1969 and 1972 had the opportunity to verify.
Cell slaughter
Researchers at Stony Brooke University cultured lung and brain cell lines (from humans and mice, respectively) and exposed them for long periods of time to the designer regolith, with the results noted above. 90% of the cells were abnormal and died , sometimes with significant DNA alterations.
It is not known why this happens to them for sure, but experts at first attribute it more to the shape and size of the moondust than to its chemical composition. “If stays on the Moon last weeks, months or even longer, it will be very difficult to eliminate the risks in the lungs of astronauts,” said biochemist Bruce Demple, lead author of the study.
Although perhaps what has most surprised researchers is that the ability of synthetic regolith to generate free radicals (atoms with unpaired electrons) did not produce the expected effects in exposed cells. Ideally, the authors of the study point out, it is that NASA provides real samples of the lunar soil to deepen this line of studies.
More information: “Assessing Toxicity and Nuclear and Mitochondrial DNA Damage Caused by Exposure of Mammalian Cells to Lunar Regolith Simulant”. doi.org/10.1002/2017GH000125
