By Ben Harder
Researchers in Texas have detected the chemical perchlorate in milk, crops, and a significant portion of the state’s groundwater. However, it’s unclear how much exposure people face through food or water, and a scientific gathering has just produced a statement downplaying perchlorate’s biological effects.
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Perchlorate is known to occur naturally only in parts of Chile (SN: 10/16/99, p. 245: https://www.sciencenews.org/sn_arc99/10_16_99/fob3.htm). Most perchlorate in the environment is thought to come from Chilean fertilizer ingredients or from solid rocket fuel, which contains synthetic perchlorate.