Mars Toxic Soil Bricks research has revealed an unexpected breakthrough for future space colonization. Scientists have discovered that perchlorates — toxic chemicals found in Martian soil — may actually help produce stronger construction bricks for future habitats on the Red Planet.
The study, conducted by researchers from the Indian Institute of Science (IISc) and the University of Florida and published in PLOS One, challenges long-standing assumptions that perchlorates are purely a barrier to Mars colonization.
Why Perchlorates Were Considered a Problem
Perchlorates make up approximately 0.5–1% of Martian regolith (soil). These chemicals are toxic to most life forms and pose risks to both human health and biological experiments. They are also considered hazardous during laboratory simulations because of their reactive properties.
Most previous attempts to create bricks from Martian soil simulants excluded perchlorates entirely due to fire safety concerns. As a result, earlier research did not fully represent the real composition of Mars’ surface material.
The new Mars Toxic Soil Bricks study intentionally incorporated perchlorates into the soil simulant to better reflect actual Martian conditions.
The Biocementation Process Explained
The research focused on a technique known as biocementation — a process where bacteria bind soil particles together to form solid structures.
Scientists used a strain of Sporosarcina pasteurii, a bacterium capable of inducing mineral precipitation through a process called ureolysis. When introduced into a slurry of Martian soil simulant, water, and additives, the bacteria help create calcium carbonate bonds that act like cement.
However, bacteria alone were not sufficient to produce strong bricks. The team experimented with multiple ingredient combinations to determine what produced the highest compressive strength.
The Role of Guar Gum and Other Additives
One key addition was guar gum, a natural plant-based adhesive derived from guar beans. When combined with bacteria and soil simulant, guar gum significantly improved structural integrity.
The gum appears to serve two purposes:
- Acting as an adhesive to bind particles
- Providing nutrients that support bacterial growth
Interestingly, nickel chloride — initially added to catalyze the chemical reaction — did not produce the strongest bricks and may not be necessary for future Mars-based construction.
The Surprising Effect of Perchlorates
The most surprising result of the Mars Toxic Soil Bricks study was that adding perchlorates to the mixture actually increased compressive strength.
The strongest bricks were formed from a combination of:
- Sporosarcina pasteurii bacteria
- Guar gum
- Perchlorate-containing soil simulant
This mixture produced bricks more than twice as strong as those made from bacteria and guar gum alone.
Researchers speculate that exposure to perchlorates triggered the bacteria to form a dense extracellular matrix (ECM). This structure creates microscopic “bridges” between bacterial cells and surrounding minerals, potentially enhancing mechanical strength.
Although perchlorates are toxic, the stress they place on bacteria may prompt adaptive responses that ultimately improve structural performance.
Why This Matters for Mars Missions
Transporting building materials from Earth to Mars would be prohibitively expensive. Future missions rely heavily on in-situ resource utilization (ISRU) — the use of local materials for construction and survival.
If Martian soil can be converted into durable building blocks using native chemicals and biological processes, it could dramatically reduce mission costs and improve sustainability.
The findings suggest that a substance once seen as a major obstacle to colonization might instead become a valuable construction asset.
Next Steps in Research
Scientists caution that more research is needed to fully understand the mechanism behind the increased strength. Future studies aim to:
- Analyze how the extracellular matrix contributes to durability
- Test long-term structural performance under Martian conditions
- Explore scalability for habitat construction
The research opens the possibility that toxic Martian soil components may serve practical engineering purposes, redefining how scientists approach extraterrestrial construction.
This report is part of FFRNEWS Astronomy & Space coverage, tracking breakthroughs in space exploration and sustainable off-world construction technologies.
Details in this article are based on reporting by Universe Today and findings published in PLOS One by researchers from the Indian Institute of Science and the University of Florida.
