A study published this week in the Journal of Geophysical Research: Solid Earth has found aluminum ore buxite to be causing high calcium content in homes.
Researchers found the mineral is “extremely soluble in water and highly acidic,” with levels of calcium in the soil at levels as high as 14,000 parts per million, according to the study.
The study was led by Dr. Matthew R. Linder, a researcher at the University of California, Santa Cruz.
It found aluminum sulfate, which is a byproduct of the refining of aluminum ore in California, was the most abundant metal in the samples.
In addition, aluminum sulfide is used in the manufacturing of aluminum foil and in the production of aluminium alloys for use in high-performance aircraft engines.
Aluminium sulfate is used to produce alloys in high performance engines, aircraft engines, and other aerospace applications.
Aluminum sulfide levels were higher than levels found in soil at the California coast, and higher than the levels found at sites in other parts of the United States.
The researchers found aluminum oxide, which the study said is produced from the oxidation of aluminum sulfates, was also present in the soils in large amounts.
The levels of aluminum oxide in California’s soils are similar to levels found on the coast, which makes it unlikely the sulfates have been removed by mining, the researchers wrote.
Aluminum sulfates are known to be toxic to aquatic life, including fish, aquatic birds, and invertebrates.
The research was funded by the U.S. Department of Energy.