Chlorine is a heavier-than-air yellowish-green gas with an irritating odor. It is used widely in chemical manufacturing, in bleaching, and (as hypochlorite) in swimming pool disinfectants and cleaning agents. Hypochlorite is an aqueous solution produced by the reaction of chlorine gas with water; most household bleach solutions contain 3-5% hypochlorite, and swimming pool disinfectants and industrial-strength cleaners may contain up to 20% hypochlorite. The addition of acid to hypochlorite solution releases chlorine gas, a pulmonary irritant. The addition of ammonia to hypochlorite solution releases chloramine, a gas with toxic properties similar to those of chlorine.

Chlorine gas produces a corrosive effect on contact with moist tissues, such as those of the eyes and upper respiratory tract. Exposure to aqueous solutions causes corrosive injury to the eyes, skin, or GI tract. Chloramine is less water soluble and may produce more indolent or delayed irritation.

1. Chlorine gas. The recommended workplace limit (ACGIH TLV-TWA) for chlorine gas is 0.5 ppm (1.5 mg/m³) as an 8-hour time-weighted average. The short-term exposure limit (STEL) is 1 ppm. The level considered immediately dangerous to life or health (IDLH) is 10 ppm.
2. Aqueous solutions. Dilute aqueous hypochlorite solutions (3-5%) commonly found in homes rarely cause serious burns but are moderately irritating due to presence of sodium hydroxide. However, intentional massive ingestions or more concentrated industrial cleaners (20% hypochlorite) are much more likely to cause serious corrosive injury.

1. Inhalation of chlorine gas. Symptoms are rapid in onset owing to the water solubility of chlorine. Immediate burning of the eyes, nose, and throat occurs, accompanied by coughing. Wheezing also may occur, especially in patients with pre-existing bronchospastic disease. With prolonged or concentrated exposure, upper airway swelling can rapidly cause airway obstruction, preceded by croupy cough, hoarseness, and stridor. With massive exposure, noncardiogenic pulmonary edema (chemical pneumonitis) and adult respiratory distress syndrome (ARDS) occurs.
2. Skin or eye contact with gas or concentrated solution. Serious corrosive burns may occur. Manifestations are similar to those of other acidic corrosive exposures.
3. Ingestion of aqueous solutions. Immediate burning in the mouth and throat is common, but no further injury is expected after ingestion of small amounts of 3-5% hypochlorite. With intentional large ingestions or more concentrated solutions, serious esophageal and gastric burns may occur, and victims often have dysphagia, drooling, and severe throat, chest, and abdominal pain. Hematemesis and perforation of the esophagus or stomach may occur.

Is based on a history of exposure and description of the typical irritating odor, accompanied by irritative or corrosive effects on the eyes, skin, or upper respiratory or GI tract.

1. Specific levels are not available.
2. Other useful laboratory studies include, with ingestion, CBC, electrolytes, and chest and abdominal radiographs; with inhalation, arterial blood gases or oximetry and chest radiography.

1. Emergency and supportive measures
   1. Inhalation of chlorine gas
      1. Immediately give humidified supplemental oxygen. Observe carefully for signs of progressive upper airway obstruction and intubate the trachea if necessary.
      2. Use bronchodilators for wheezing and treat noncardiogenic pulmonary edema if it occurs.
   2. Ingestion of hypochlorite solution. If a solution of 10% or greater has been ingested, or if there are any symptoms of corrosive injury (dysphagia, drooling, or pain), flexible endoscopy is recommended to evaluate for serious esophageal or gastric injury. Obtain chest and abdominal radiographs to look for mediastinal or intra-abdominal air, which suggests perforation.
2. Specific drugs and antidotes. There is no proven specific treatment. Inhalation of dilute nebulized 2% sodium bicarbonate solutions continues to be advocated, although only modest benefits are reported. Inhaled and systemic corticosteroids have no clear role and could potentially be harmful in patients with perforation or serious infection.
3. Decontamination
   1. Inhalation. Remove immediately from exposure and give supplemental oxygen if available. Administer inhaled bronchodilators if wheezing is present.
   2. Skin and eyes. Remove contaminated clothing and flush exposed skin immediately with copious water. Irrigate exposed eyes with water or saline.
   3. Ingestion of hypochlorite solution. May give water by mouth if tolerating secretions. Do not induce vomiting. Gastric aspiration may be useful after concentrated liquid ingestion in order to remove any corrosive material in the stomach and to prepare for endoscopy; use a small, flexible tube to avoid injury to damaged mucosa.
   4. Do not use activated charcoal; it may precipitate vomiting and obscure the endoscopist's view.
4. Enhanced elimination. There is no role for enhanced elimination.