The chloride ion is formed when the element chlorine picks up one electron to form the Cl- anion. The chloride ion is one of the most common anions in nature and is necessary to most forms of life. It is an essential electrolyte responsible for maintaining acid/base balance and regulating fluid in and out of cells. [Wikipedia]
In nature, chlorine is most abundant as a chloride ion. Physiologically, it exists as an ion in the body. The chloride ion is an essential anion that the body needs for many critical functions. Chloride is a prominent negatively charged ion of the blood, where it represents 70% of the body’s total negative ion content. On average, an adult human body contains approximately 115 grams of chloride, making up about 0.15% of total body weight. The suggested amount of chloride intake ranges from 750 to 900 milligrams per day, based on the fact that total obligatory loss of chloride in the average person is close to 530 milligrams per day. Chloride helps keep the body's acid-base balance. The amount of chloride in the blood is carefully controlled by the kidneys. In addition to its functions as an electrolyte, chloride combines with hydrogen in the stomach to make hydrochloric acid, a powerful digestive enzyme that is responsible for the break down of proteins, absorption of other metallic minerals, and activation of intrinsic factor, which in turn absorbs vitamin B12. Chloride ions also have other important physiological roles. For instance, in the central nervous system, the inhibitory action of glycine and some of the action of GABA relies on the entry of Cl- into specific neurons. Also, the chloride-bicarbonate exchanger biological transport protein relies on the chloride ion to increase the blood's capacity of carbon dioxide, in the form of the bicarbonate ion. Chloride-transporting proteins (CLC) play fundamental roles in many tissues in the plasma membrane as well as in intracellular membranes. CLC proteins form a gene family that comprises nine members in mammals, at least four of which are involved in human genetic diseases. GABA(A) receptors are pentameric complexes that function as ligand-gated chloride ion channels. WNK kinases are a family of serine-threonine kinases that have been shown to play an essential role in the regulation of electrolyte homeostasis, and they are found in diverse epithelia throughout the body that are involved in chloride ion flux. Cystic fibrosis (CF) is caused by alterations in the CF transmembrane conductance regulator (CFTCR) gene that result in deranged sodium and chloride ion transport channels. (A7709, A7710, A7711, A7712, A11065).
Compound Health Effects
- Metabolism: In humans, 88% of chloride is extracellular and contributes to the osmotic activity of body fluids. The electrolyte balance in the body is maintained by adjusting total dietary intake and by excretion via the kidneys and gastrointestinal tract. Chloride is almost completely absorbed in normal individuals, mostly from the proximal half of the small intestine. Normal fluid loss amounts to about 1.5–2 litres/day, together with about 4 g of chloride per day. Most (90– 95%) is excreted in the urine, with minor amounts in faeces (4–8%) and sweat (2%). A normal adult human body contains approximately 81.7 g chloride. On the basis of a total obligatory loss of chloride of approximately 530 mg/day, a dietary intake for adults of 9 mg of chloride per kg of body weight has been recommended.
- Uses/Sources: Chloride is found in table salt as well as most foods. Chloride is an essential element or micronutrient and helps keep the body’s electrolyte balance.
- Health Effects: The oral ingestion of larger quantities of sodium chloride, eg 1000 g in 600 mL of water, is harmful and can induce irritation of the gastrointestinal tract, vomiting, hypernatremia, respiratory distress, convulsions, and death. Hyperchloremia can also occur due to loss of body fluids from prolonged vomiting, sweating or fever, kidney failure, kidney disorders or diabetes. Hyperchloremia is associated with deep and labored breathing, weakness, and intense thirst. Cystic fibrosis (CF) is caused by alterations in the CF transmembrane conductance regulator (CFTCR) gene that result in deranged sodium and chloride ion transport channels. This leads to the production of very salty sweat and the excessive production of mucous in the lungs. More than 100 genetic diseases or inborn errors of metabolism are associated with electrolyte (i.e. chloride) imbalances.
- Symptoms: Hyperchloremia can be symptomatic with signs of deep and labored breathing (often associated with severe metabolic acidosis, particularly diabetic ketoacidosis (DKA) but also renal failure), weakness, and intense thirst.
- Treatment: As with most types of electrolyte imbalance, the treatment of high blood chloride levels is based on correcting the underlying cause. If the patient is dehydrated, therapy consists of establishing and maintaining adequate hydration. If the condition is caused or exacerbated by medications or treatments, these may be altered or discontinued, if deemed prudent. If there is underlying kidney disease (which is likely if there are other electrolyte disturbances), then the patient will be referred to a nephrologist for further care. If there is an underlying dysfunction of the endocrine or hormone system, the patient will likely be referred to an endocrinologist for further assessment.
- Route of Exposure: Inhalation (L247) ; dermal (L247)