Less-lethal law enforcement weapons: clinical management of associated injuries in the emergency department

Less-lethal weapons and tactics are being increasingly used by law enforcement to minimize the reliance on more-lethal force. While these methods are designated as "less-lethal," they can cause morbidity and mortality when deployed. Knowledge of these weapons and tactics can help direct the workup and management of patients with injuries from these methods and can protect clinicians from secondary exposure and injuries. This issue reviews the most common less-lethal weapons and tactics used by law enforcement, describes their mechanism of action, and discusses associated common injury patterns. Recommendations are provided for the evaluation and management of these patients in the emergency department.

[Injuries from pepper spray used for self defense: analysis of 15 cases managed in an emergency chemical decontamination area]

We analyzed epidemiologic and clinical characteristics, treatment received, and clinical course in cases of pepper spray injury treated in the chemical decontamination area of an emergency department over a 5-year period. A total of 15 patients with a mean (SD) age of 25 (8.3) years were included. Thirteen were men and 53% were foreign-born. All uses of pepper spray occurred during muggings that to place mainly in the early hours of the morning (66.7% between 4:30 and 6:30 AM). Two or more attackers were injured in 60% of the events. Seventy-three percent of the attacks took place on the street and the median delay in reaching the emergency department was 30 minutes. The face and eyes were usually injured, and symptoms included itching, irritation, burning, and pain. On arrival, the patients were treated immediately (mean delay, 3 minutes) with hypertonic saline, an amphoteric surfactant, and a chelating agent in 80% of the cases, in which improvement was substantial as mean pain scale scores changed from 7.2 on admission to 3 on discharge (P=.009). Patients spent an average of 40 minutes in the treatment area. Eleven patients required further care from an ophthalmologist and topical medication for symptoms. Outcomes were good and there were no complications in any of the cases. We conclude that pepper sprays are being used as an aid to self defense in muggings in our community. Decontamination measures have priority as they alleviate symptoms and prevent long-lasting effects.

Is the pepper spray a triggering factor in myocardial infarction? A case report

Forty-year-old man was admitted to emergency department with complains of chest pain and dispnea after exposure the pepper gas that sprayed to environment during a social event. Physical examination and electrocardiogram was revealed acute myocardial infarction.

Accidental tear gas injuries in security agents

BACKGROUND

Tear gas is a noxious vapour used in quelling civil disturbances. The law enforcement agents who usually handle this are well trained and rarely injured by the use of this weapon especially during peace times.

METHODS

We report injuries sustained by two policemen handling tear gas as a result of accidents. Case notes of the patients were the source of information.

RESULTS

Two policemen were injured while handling tear gas. The equipment accidentally dropped and exploded on attempting to pick them. The mechanisms of injuries and parts of the body injured were similar ie the hands and face with traumatic cataract of an eye in one patient.

CONCLUSION

We conclude that proper training of the law enforcement agents will go a long way in reducing these types of morbidity from tear gas use.

Medical hazards of the tear gas CS. A case of persistent, multisystem, hypersensitivity reaction and review of the literature

A 30-year-old incarcerated man was sprayed with the "tear gas" ortho-chlorobenzylidene malononitrile (CS). He was hospitalized 8 days later with erythroderma, wheezing, pneumonitis with hypoxemia, hepatitis with jaundice, and hypereosinophilia. During the subsequent months he continued to suffer from generalized dermatitis, recurrent cough and wheezing consistent with reactive airways dysfunction syndrome, and eosinophilia. These abnormalities responded to brief courses of systemic corticosteroid but recurred off therapy. The dermatitis resolved gradually over 6-7 months, but the patient still had asthma-like symptoms a year following exposure. Patch testing confirmed sensitization to CS. The mechanism of the patient's prolonged reaction is unknown but may involve cell-mediated hypersensitivity, perhaps to adducts of CS (or a metabolite) and tissue proteins. This is the first documented case in which CS apparently caused a severe, multisystem illness by hypersensitivity rather than direct tissue toxicity. Both the ethics and safety of CS use remain controversial, in part because of the difficulty documenting sporadic injuries received in the field, and also because the charged circumstances surrounding CS use may lead to both underreporting and exaggerated claims of medical harm. The medical literature on CS focuses mainly on its immediate irritant effects and on transient dermal and ocular injuries, with only 2 prior case reports of acute lung injury related to CS exposure. Given the paucity of documented lasting effects despite its widespread use for more than 3 decades, CS appears to be safe when deployed (outdoors) in a controlled manner, but it can cause important injuries if misused or if applied to a sensitized individual.

[Occupational asthma in a teacher after repeated exposure to tear gas]

Acute exposure to tear gas causes generally reversible cutaneous and mucosal irritations. Lasting respiratory manifestations after exposure are exceptional. We report the case of a 26-year-old female teacher with no history of respiratory disease who developed asthma after repeated exposure to tear gas discharged in her class room. The disorders occurring during these repeated exposures to the irritating gas were consistent with the recently described low level reactive airway dysfunction syndrome (low level RADS).

Occupational contact dermatitis due to 2-chloracetophenone tear gas

2-Chloracetophenone (CN) is widely used as tear gas by police and civilians for self-defence. It may affect the eyes, respiratory system and skin, sometimes causing serious injuries. Both irritative and allergic contact dermatitis have been described. We report three police officers who experienced accidental escape of CN from their professional tear gas canisters. All of them showed localized dermatitis at the site of contact to CN, while widespread lesions appeared after 4 days in one case. Patch tests with the original involved tear gas dissolved in acetone (at 0.1-0.0001%) indicated an allergic reaction in two patients and an irritative reaction in the third. Occupational contact dermatitis due to CN seems to occur among police officers more often than is generally known. Infrequently, extensive health problems may be caused by CN when lesions spread over the integument. Therefore, an improvement of safety measures in occupational CN gas use is needed, especially aiming at avoidance of accidental leakage of canisters.

Acute effects of the potent lacrimator o-chlorobenzylidene malononitrile (CS) tear gas

1. The use of tear gas to control civil unrest is accepted practice by government authorities worldwide. It is rarely used in Hong Kong but during a recent riot at a Vietnamese detention centre large quantities were used and this was cause for some concern. 2. All patients presenting to the British Red Cross Clinic after the incident were seen by one of the authors. To establish if exposure to tear gas had serious effects on the health of the detainees, the case records of the 184 patients with symptoms consistent with CS exposure were reviewed 2 months later. 3. The most common complaints were burns (52%), cough (38%), headache (29%), shortness of breath (21%), chest pain (19%), sore throat (15%) and fever (13%). However, the only common findings on examination by a physician were burns (52%) and an inflamed throat (27%). All burns could be categorised as "minor' according to the American Burns Association classification and all were consistent with CS gas exposure. 4. Some patients complained of other symptoms that had not been previously reported in the literature, such as haemoptysis (8%) and haematemesis (4%), but these were only confirmed in one patient. 5. The majority of patients had recovered within 2 weeks of exposure although one asthmatic patient complained of shortness of breath lasting for 33 days and a sore throat lasting for 38 days after the incident. She had abnormally low peak expiratory flow readings, but had a clinical history of asthma. 6. No serious sequelae were encountered, but the incidence of burns in these patients was higher than would be expected from a review of the literature. However, very little data on the effects of tear gas in a riot situation has been published. There have been reports of high concentrations of CS gas causing reactive airways dysfunction but this was not seen in our group of patients.

Acute mass burns caused by o-chlorobenzylidene malononitrile (CS) tear gas

The use of tear gas in controlling riots has been an accepted practice in many countries for the past four decades. In a recent event, a large quantity of tear-gas canisters were used during a situation of unrest in a Hong Kong Refugees' Detention Centre. We report 96 cases of acute burn injury as an unpredicted side effect of o-chlorobenzylidene malononitrile (CS) tear gas. There were 47 females and 49 males with an age ranging between < 1 to 51 years. These burns were categorized as minor burns, with the total body surface area (TBSA) ranging from 1 to 8 per cent with mean percentage of 3. Most of the patients sustained superficial or partial-skin thickness injuries. Only two patients were admitted to the Prince of Wales Hospital Burns Centre because of deeper burns; debridement and skin grafting was required in one of them. The mechanism of burn injury was due to the flame generated from the grenade explosion, direct contact between the hot canister and the victim's skin, and the effect of the chemical powder inside the canisters when it splashed onto the victim's body. We suggest that the noxious transient effects of tear gas are underestimated, furthermore varying cutaneous effects and deep burns may result from its uncontrolled use during riots. There is a continuing need to reassess the potential toxic effects of CS tear gas as a riot control agent and to debate whether its future use can be condoned under any circumstances.

Personal aerosol protection devices: caring for victims of exposure

The increased incidence of violence in our society has led to a concern for personal safety. For self-protection, many individuals are turning to personal aerosol protection devices (PAPDs), which are readily accessible to the general public. The greater use and misuse of these noxious chemicals has led to an increase in injuries associated with exposure. Health care providers need to be aware of the modes of action of PAPDs, the presenting exposure symptoms, first aid measures, and decontamination procedures of the environment and the victim's belongings. This article provides a thorough discussion of PAPDs and will assist the clinician in delivering primary care and health education to victims of PAPD exposures.

[Lymphocyte stimulation test, a possible alternative for verifying chloroacetophenone sensitization]

We report on a case of pronounced sensitization to chloroacetophenone tear gas that developed after repeated occupational skin exposure in a 57-year-old police officer. Mainly in the presence of moisture and occlusion, cutaneous application of chloroacetophenone leads to severe irritant, and often also allergic, skin reactions. In patch testing the demonstration of allergic contact dermatitis in response to chloroacetophenone is hampered by the irritative potential of this substance even at low concentrations. This diagnostic bias can be overcome by the lymphocyte proliferation assay.

[The gas weapon--a new problem for forensic toxicology]

Current status of the problem of toxicologic assessment of irritants used for gas weapon charge is presented, classification and parameters of toxicity of clinical picture in poisoning with, and mechanisms of toxic action of irritants are described. Trends in research aimed at improvement of forensic medical diagnosis of lesions caused by irritants are discussed.

[Keratopathy due to a spray]

The paper presents seven cases of corneo-conjunctival lesions produced by anti-aggressional spray. The corneal lesions were superficial and do not exceed in depth the Bowman membrane. Besides the ocular lesions, the patients presented irritative cough and general manifestations represented by a transient motor deficit, which produced the decrease of the defense capabilities during 15-30 minutes. The ocular lesions had a favourable evolution, excepting two cases with more severe evolution.

[Tear gas and eye injuries]

In the course of the last year, the Eye Clinic, Ullevål hospital has treated six cases of corneal injury caused by violent use of tear gas spray cannisters. In some cases there was total abrasion of the corneal epithelium, which could take several weeks to heal. We want to draw attention to this "weapon", the use of which seems to be spreading among young people.

[Contact allergies to CN and CS ("tear gas") in participants in demonstrations]

56 occasional demonstrators were interviewed with regard to former skin contact with omega-chloroacetophenone (CN) or ortho-chlorobenzylidene malononitrile (CS). 33 persons (59%) reported skin reactions of various kinds. Patch testing with CN, the structurally related preservative chloroacetamide, and CS revealed clinically relevant reactions to CN in 3 cases and questionable positive reaction to CS in one case. 8 further patients showed mild reactions to CN and CS. We did not find any indication of cross reactions between CN and chloroacetamide.

Tear gas--harassing agent or toxic chemical weapon?

Tear gas has gained widespread acceptance as a means of controlling civilian crowds and subduing barricaded criminals. The most widely used forms of tear gas have been o-chlorobenzylidenemalononitrile and omega-chloroacetophenone. Proponents of their use claim that, if used correctly, the noxious effects of exposure are transient and of no long-term consequences. The use of tear gas in recent situations of civil unrest, however, demonstrates that exposure to the weapon is difficult to control and indiscriminate, and the weapon is often not used correctly. Severe traumatic injury from exploding tear gas bombs as well as lethal toxic injury have been documented. Moreover, available toxicological data are deficient as to the potential of tear gas agents to cause long-term pulmonary, carcinogenic, and reproductive effects. Published and recent unpublished in vitro tests have shown o-chlorobenzylidenemalononitrile to be both clastogenic and mutagenic. Sadly, the nature of its use renders analytic epidemiologic investigation of exposed persons difficult. In 1969, eighty countries voted to include tear gas agents among chemical weapons banned under the Geneva Protocol. There is an ongoing need for investigation into the full toxicological potential of tear gas chemicals and renewed debate on whether their use can be condoned under any circumstances.

[CS tear gas spray as an injurious agent. Clinical aspects]

Eight cases are described, in which illegally imported CS-tear gas spray ("self-defence spray") were used in connection with malice or robbery. Analysis of the content of the sprays revealed small amounts of CS (0.2 per cent), but large amounts of solvents and propellants. The latter are presumed to have contributed to the symptoms. Exposure to CS-tear gas spray is usually harmless, but skin manifestations such as ulcerations, Quincke-like oedema in the face and allergic dermatitis have been reported by other authors. Theoretically, CS-particles may adhere to the cornea. Examination of the eye is therefore recommended.

Medical problems and criteria regarding the use of tear gas by police

Litigation against police agencies for the use and misuse of control agents and procedures has become an important issue for the forensic medical specialist and expert witness. As police technology improves, it becomes apparent that more information for forensic experts will be required in this area. One such area of concern is the use of tear gas by police. This paper addresses the basic types of gas in terms of their chemistry, uses, and medical side effects and complications. Two types of gases--namely, chloroacetophenone (CN) and orthochlorobenzylidenemalontrile (CS)--are discussed in terms of basic properties, unique advantages, and possible harm to the body. CN and CS are relatively safe agents that can be used to control the behavior of a dangerous person. Clinical examples of their use and misuse by police are also reported. Specific guidelines are offered to help ensure a proper assessment of the dangerous person and to protect the health and lives of police personnel, perpetrators, and others exposed to the tear gas. Forensic experts called to testify about the behavior of the disturbed person or to assess the appropriateness of action taken to subdue that person must become more aware of the technology employed by police agencies to accomplish this particular job of protecting public safety.

[Contact allergy to CN and CS tear gas]

Tear gases are used as riot control agents on account of their irritant properties. Five cases of allergic contact dermatitis due to omega-chloroacetophenone (CN) and one case additionally due to 2-chlorobenzylidene-malonitrile (CS) are reported.