The U.S. government has come under fire after reports surfaced that U.S. Border Patrol agents used tear gas on a group of migrants—including children—who rushed the U.S.-Mexico border on Sunday.
About 500 migrants on the Mexico side of the border reportedly overwhelmed police blockades near the San Ysidro Port of Entry, prompting border patrol agents to respond with tear gas, according to CNN. Videos taken by journalists at the scene capture adults and barefoot children in diapers running and screaming after being exposed to the chemical weapon.
The U.S. Customs and Border Protection tweeted on Sunday that agents utilized the tear gas after “several migrants threw projectiles at the agents in San Diego," requiring them "to dispel the group because of the risk to agents' safety.” The 1993 Chemical Weapons Convention banned the international use of chemical weapons—including tear gas—in warfare. However, some countries, including the U.S., still use it for riot control.
While the physical effects of tear gas in many cases are temporary, being attacked with a chemical irritant does cause short-term issues and can be destabilizing in many ways, both physically and emotionally. These are some of the ways this weapon can take a toll on the body.
Tear gases are chemical compounds that irritate the eyes, skin, lungs, and more, and in turn, make people unable to function, as the Centers for Disease Control and Prevention (CDC) explains.
Tear gases are considered lachrymator substances, meaning they cause a tearing effect of the eyes, and often times other uncomfortable symptoms. The most common types are Agent CS (chlorobenzylidenemalononitrile) and Agent CN (chloroacetophenone), although there are other compounds considered to be tear gases as well. Often grouped with tear gas is Agent OC (oleoresin capsicum), or pepper spray, or its synthetic form known as PAVA spray, according to the American Civil Liberties Union (ACLU).
Agent OC and PAVA work on pain and temperature receptors in your body to incite a pain response, ACLU explains. Even small amounts can penetrate your skin and enter mucus membranes to cause severe and drawn-out pain that may last a half hour. Tear gas chemical compounds, like OC, dissolve and become a painful acidic liquid when they come into contact with water, sweat, or oil on a person’s skin or mucus membranes, the ACLU says. The moisture in the respiratory tract and mucus membranes makes these areas especially sensitive to these agents.
Exposure to tear gas temporarily causes unpleasant pain and side effects.
“The known impact of tear gas is not great for your health, and then there are side effects and unintended consequences that are also not great,” Rohini J. Haar, M.D., M.P.H., a medical research and investigations advisor at Physicians for Human Rights and a visiting professor at the UC Berkeley School of Public Health, tells SELF.
In general, tear gas causes a stinging and burning sensation to a person’s eyes and mucus membranes (including those in the lungs), salivation, watery eyes, runny nose, tight chest, headache, and nausea, the World Health Organization (WHO) says.
“It causes your skin to feel like it’s burning and, when you breathe it in (which you can’t help but do because it’s a gas), it can cause injury to your airways and lungs,” Dr. Haar explains. “All of the symptoms are supposed to be temporary, like lasting 20 to 30 minutes, but if you can’t get out of the tear gas, there’s too much of it, or you’re specifically vulnerable to it, it can cause a lot more problems.”
Other health issues that tear gas exposure can lead to include chronic skin reactions and chemical burns to your skin, a corneal abrasion (a painful scratch on the transparent front part of your eye), and long-lasting or permanent lung injury such as inflammation of the airways—and these side effects could take weeks or longer to improve. If a person has a preexisting condition like asthma, they’re also more sensitive to respiratory distress or hypoxia, which is a condition where people can’t get enough oxygen into their bodies, Dr. Haar says. Also, sometimes the canisters themselves can cause injury. “We’ve seen skull and bone fractures after people were hit with them,” she adds.
In general, children are more vulnerable to these effects, Dr. Haar says.
“Their skin is more fragile and more sensitive, and it can be penetrated more easily than that of an adult,” she explains. Children can also experience pain more acutely than adults and may be exposed to tear gas for a longer period than older people because they don’t know how to react and seek protection as hastily. “Kids don’t know to close their eyes tightly and will keep them open, and they’ll also keep their mouth open because they’re screaming for their mothers, increasing their exposure,” Dr. Haar notes. “That’s not to mention the psychological impact of experiencing violent trauma at such a young age.”
The longer-term effects of tear gas exposure remain unclear. Studying the long-term effects of chemical irritants is a complicated task, as researchers would have to identify and follow the people who are affected for years and years. Many existing studies on the toxicology of tear gas are small, and the study variables vary (they may look at the effects of tear gas with different amounts of the active chemical or specifically look at a military personnel population, for example, which could affect the findings).
While you may not have been directly affected by the tragic events that took place at the border on Sunday, you could be exposed to tear gas or pepper spray if you plan to participate in any protests or events where crowd-control may be an issue.
Unfortunately, there’s only so much you can do in the moment to try to protect yourself or a loved one—but the symptoms should pass relatively quickly. If you do find yourself in a situation where you must protect yourself and/or others from riot-control agents, the most important thing you can do is to get away from the gas, J. David Gatz, M.D., an emergency medicine physician at Mercy Medical Center, tells SELF. The gas is also heavier than air and will start to fall closer to the ground, so you want to get to a higher area as quickly as you can, he says.
Once you’re far enough away, it’s important to get to fresh air and flush your eyes, skin, and hair with a large amount of water. “Initially, water can make it worse, but using copious amounts of water will flush it off,” Dr. Haar notes. And, if you have access to soap, wash with it. Soap when combined with water can help remove tear gas pretty well, Dr. Gatz says. Tear gas will also hang onto your clothes, so you’ll want to get out of them and change into clean clothes as soon as you can.
If you’re still experiencing symptoms 20 to 30 minutes later, you’re having eye or lung issues, or you’re worried in any way after being exposed to tear gas, get to the ER. “It’s definitely something we occasionally see,” Dr. Gatz says. “In general, it’s mainly an irritant and symptoms should pass with time, but if you have any concern, never hesitate to go to the ER.”