Role in biology Chloride has a major physiological significance, which includes regulation of osmotic pressure, electrolyte balance and acid-base homeostasis. Chloride is  the most abundant extracellular anion and accounts for around one third of extracellular fluid  tonicity. Chloride is also a useful and reliable chemical indicator of river / groundwater fecal contamination, as chloride is a non-reactive solute and ubiquitous to sewage  potable water. Many water regulating companies around the world utilize chloride to check the contamination levels of the rivers and potable water sources.
Role in biology Chloride has a major physiological significance, which includes regulation of osmotic pressure, electrolyte balance and acid-base homeostasis. Chloride is present in all body fluids, and is the most abundant extracellular anion which accounts for around one third of extracellular fluid 's tonicity. Chloride is also a useful and reliable chemical indicator of river / groundwater fecal contamination, as chloride is a non-reactive solute and ubiquitous to sewage and potable water. Many water regulating companies around the world utilize chloride to check the contamination levels of the rivers and potable water sources.
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