Health issues and healthcare utilization among adults who reported exposure to tear gas during 2020 Portland (OR) protests: a cross-sectional survey

Less-Lethal Weapons and Civilian Injury in Police Use of Force Encounters: A Multi-agency Analysis

Police use-of-force is a growing public health concern, with recent estimates suggesting that over 70,000 people are injured by police each year. To reduce the risk of injury to civilians, most police agencies authorize the use of various less-lethal weapons. However, to date, there is little consensus as to which types of less-lethal weapons are most effective at reducing injury risk. In this study, we test the differential effects of less-lethal weapons on civilian injury and injury severity using data on 2348 use-of-force incidents originating from 17 large urban and metropolitan law enforcement agencies from 2015 to 2019. Specifically, we assess the injury risks associated with conducted energy devices, chemical agents, impact weapons, and police canines, while controlling for a robust set of officer, civilian, and situational characteristics. Our results indicate that chemical agents reduce the risk of hospitalization or death significantly more than other weapon types, while police canines increase the risk of all injury outcomes significantly more than other weapon types. Adjusting for incident characteristics, chemical agents are predicted to cause hospitalization or death in 4% of cases, compared to 13% for conducted energy devices, 16% for impact weapons, and 37% for police canines. These findings suggest that civilian injury may be reduced through use-of-force policies that prioritize less severe modalities of force, though more research is needed on the contextual and long-term effects of these weapons.

Pharmacologic Inhibition of Transient Receptor Potential Ion Channel Ankyrin 1 Counteracts 2-Chlorobenzalmalononitrile Tear Gas Agent-Induced Cutaneous Injuries

Deployment of the tear gas agent 2-chlorobenzalmalononitrile (CS) for riot control has significantly increased in recent years. The effects of CS have been believed to be transient and benign. However, CS induces severe pain, blepharospasm, lachrymation, airway obstruction, and skin blisters. Frequent injuries and hospitalizations have been reported after exposure. We have identified the sensory neuronal ion channel, transient receptor potential ankyrin 1 (TRPA1), as a key CS target resulting in acute irritation and pain and also as a mediator of neurogenic inflammation. Here, we examined the effects of pharmacologic TRPA1 inhibition on CS-induced cutaneous injury. We modeled CS-induced cutaneous injury by applying 10 μl CS agent [200 mM in dimethyl sulfoxide (DMSO)] to each side of the right ears of 8- to 9-week-old C57BL/6 male mice, whereas left ears were applied with solvent only (DMSO). The TRPA1 inhibitor HC-030031 or A-967079 was administered after CS exposure. CS exposure induced strong tissue swelling, plasma extravasation, and a dramatic increase in inflammatory cytokine levels in the mouse ear skin. We also showed that the effects of CS were not transient but caused persistent skin injuries. These injury parameters were reduced with TRPA1 inhibitor treatment. Further, we tested the pharmacologic activity of advanced TRPA1 antagonists in vitro. Our findings showed that TRPA1 is a crucial mediator of CS-induced nociception and tissue injury and that TRPA1 inhibitors are effective countermeasures that reduce key injury parameters when administered after exposure. Additional therapeutic efficacy studies with advanced TRPA1 antagonists and decontamination strategies are warranted. SIGNIFICANCE STATEMENT: 2-Chlorobenzalmalononitrile (CS) tear gas agent has been deployed as a crowd dispersion chemical agent in recent times. Exposure to CS tear gas agents has been believed to cause transient acute toxic effects that are minimal at most. Here we found that CS tear gas exposure causes both acute and persistent skin injuries and that treatment with transient receptor potential ion channel ankyrin 1 (TRPA1) antagonists ameliorated skin injuries.

Social Outbreak in Chile, and Its Association with the Effects Biological, Psychological, Social, and Quality of Life

The World Health Organization has defined collective violence as the instrumental use of violence by people who identify themselves as members of a group against other individuals and have political, economic, or social objectives. In Chile, the "Social Outbreak" was used to describe an episode of collective violence, which began on October 18, 2019, triggered by a multitude of socioeconomic and political factors, with protests and mobilizations in the country's large and small cities; in central, commercial, and residential areas, that lasted for several months, affecting a large part of the population. The objective of the present study was to associate the social outbreak in Chile with its biological, psychological, and social effects on people's health and quality of life, as well as its characteristics in terms of exposure, proximity, type, and frequency. This was a cross-sectional study with non-probabilistic national-level sampling, conducted from 28 November 2019, to 3 March 2020. The instrument had four sections. A total of 2651 participants answered the survey; 70.8% were female, and the mean age was 35.2. The main disturbances perceived were protests (70.9%), alarm sounds (68.1%), shooting sounds (59.0%), and tear gas bombs (56.9%). When quantifying the magnitude of these associations, people who had a medium exposure have a higher probability (OR: 1.99, CI: 1.58; 2.50) of suffering three or more biological effects than people that have a low exposure, while people with higher exposition have a 4.09 times higher probability (CI: 3.11; 5.38). A similar pattern was observed regarding psychological effects, although social effects were primarily experienced by those with high exposure. Social networks, TV, and radio were the most used media among people who perceived a greater effect. People who lived, worked, or shopped near the disturbance's areas show a higher proportion negative effect.

More than tears: associations between exposure to chemical agents used by law enforcement and adverse reproductive health outcomes

Despite routine law enforcement use of chemical agents for crowd control, the reproductive health safety profiles of these products are unknown. Moreover, limited evidence has documented a link between such exposures and adverse reproductive health outcomes including abnormal uterine bleeding and potential pregnancy disruption. This cross-sectional study examined reproductive outcomes in adults with uteri exposed to chemical agents used by law enforcement, more commonly known as "tear gas". Participants were recruited through social media in the wake of police violence protests. Of the 1,276 participants included in analysis, 83% reported experiencing at least one of the outcomes of interest, included uterine cramping (69%), early menstrual bleeding (55%), breast tenderness (30%), and delayed menstrual bleeding (19%). Chemical agent exposure was significantly associated with higher odds of an adverse reproductive health outcome, those with 5 days or more of exposure have 2.6 times the odds (CI: 1.61, 4.22) of adverse outcomes and having a perception that one's menstruation may fluctuate according to psychosocial stressors was associated (OR = 1.94, CI: 1.36, 2.79) with a higher odds of an adverse reproductive health experience. These findings suggest a potential relationship between exposure to chemical agents and adverse reproductive health outcomes. Given the pervasive use of these chemical agents and their potential for reproductive health harm, further investigation into the safety of these products and their impacts on individual and community health is warranted urgently.

Reevaluating tear gas toxicity and safety

Tear gases, or chemical demonstration control agents (DCA), were originally created as weapons that could severely disable or kill enemy troops. Though banned in war, these chemicals are still used in domestic policing. Here we review the available scientific literature on tear gas, summarizing findings from animal and environmental studies as well describing data from new human studies. We find a lack of scientific evidence supporting the safety of tear gas, especially regarding its long-term impacts on human health and the environment. Many of the available studies were published decades ago, and do not parse data by variables such as chemical type and exposure time, nor do they account for the diversity of individuals who are exposed to tear gas in real-life situations. Due to the dearth of scientific research and the misinterpretation of some of the available studies, we conclude that a serious reevaluation of chemical DCA safety and more comprehensive exposure follow-up studies are necessary.