Short-term health effects of tear agents chlorobenzylidenemalononitrile and oleoresin capsicum during the civil riots of Santiago de Chile in 2019–2020

Chlorobenzylidenemalononitrile (CS) and Oleoresin Capsicum (OC) were tear gasses used as anti-riot control agents during social unrest riots in Chile (October 2019-March 2020). This study posed as a research question what were the short-term health effects of CS and OC and their patterns of temporal occurrence in a sample of inhabitants and health care volunteer brigades of the Plaza Italia (city of Santiago, Chile) during the riots. A retrospective cross-sectional study was conducted in 112 exposed people (inhabitants and health care volunteers) affected by CS and OC. 62 harmful effects were studied classified in three time periods of occurrence: immediate effects (between exposure and one hour), secondary effects (from one hour after exposure and up to 24 h), and subsequent effects (days after exposure). The use of CS and OC in Santiago riots 2019-2020 produced harmful effects on both groups: inhabitants and brigade health care volunteers. The frequency of effects was, from most to least common: 62.5% eye pain or burning, 56.2% throat irritation, 54.4% respiratory distress, 52.6% skin pain or burning, 51.7% impaired vision, 37.5% skin erythema, 31.2% headache, 31.2% irregular breathing, 25.8% conjunctival injection, 29.4% nausea, 27.6% disorientation, 26.7 high blood pressure, 25.8% lip pain, 24.1% rhinitis, 24.1% skin sensitivity, 22.3% diarrhea, 20.5% contact dermatitis, 18.7% conjunctivitis, 16.9% skin vesicles, 16% tachycardia, 14.4 cough with phlegm and 9.8% corneal abrasion. 22 effects were more frequent (<i>p</i> < 0.05) in health care volunteers than among residents. High blood pressure was more frequent (<i>p</i> < 0.05) among residents. Immediate most frequent effects were pain or burning, impaired vision, respiratory difficulty, irregular breathing, skin pain and burning, skin erythema, nausea, tachycardia, and hypertension. Secondary effects were diarrhea, skin vesicles, and eye pain or burning. Subsequent most frequent effects among healthcare personnel were conjunctivitis, skin pain, burning, rhinitis, and diarrhea. Among residents, the most common effects were skin pain, burning, and impaired vision.