A comparative study between the lunar soil simulant (LSS) and PM2.5 was performed to discover their harm to human biological systems and explore the methods of prevention and treatment of dust poisoning for future lunar manned landings. The steps to the moon never stopped after the Apollo Project. Lessons from manned landings on the moon have shown that lunar dust has great influence on the health of astronauts.

They aim to land on the far side of the moon, and the aim to collect lunar samples to be analyzed on Earth, have already been planned to launch in the coming years. After that, China also has the strategy to send astronauts to the lunar surface. However, lunar dust is the primary environmental challenge that astronauts must face during manned landings.

To protect the health and safety of astronauts exposed to lunar dust is one of the most important issues to research. Lunar dust is one of the most serious challenges that mankind must face in future manned lunar missions. NASA once carried out a preliminary study of the toxicity to assess the risk when people are exposed to lunar dust and set the standards to protect the astronauts.

China has completed many lunar explorations in recent decades and had the ambition to send astronauts to the moon surface; however, research on lunar dust toxicity is still rare. Therefore, evaluating lunar dust toxicity is essential and necessary for future manned lunar exploration.

Because real lunar soil is very rare, the CAS-1 lunar soil simulant developed by scientists in China was used as a substitute for real lunar soil in this study. This is practical because both the CAS-1 lunar soil simulant and lunar samples from Apollo 14 have almost the same mineral composition, chemical composition, and physical and mechanical properties.

In this paper, the results of lung histopathology also indicated that rat lung tissue showed inflammation caused by lunar dust. Additionally, the severity worsened with the increase of the dose and time. From the test results, LSS may show more pulmonary toxicity than PM2.5. Moreover, LSS could cause lung parenchymal damage and generate inflammatory lesions.

This study evaluated the acute effects on rat lungs of two types of dust, PM2.5, and LSS. The changes in the biomarkers in the BALF were consistent with the results of histopathological observations. Of course, research on LSS cannot fully reflect the true toxicity of lunar dust, but it will help us to understand better the dangers of manned lunar explorations.

In the above experiments with limited conditions, the non-uniformity of the dust particle size may also have affected the results, but this issue will be improved in a future study.