Maria Meza, 40, a migrant from Honduras, runs away from tear gas with her 5-year-old twin daughters, Saira Mejia Meza, left, and Cheili Mejia Meza, in front of the border wall in Tijuana, Mexico, on Sunday. (Kim Kyung-Hoon/Reuters)

Irwin Redlener, a professor at the Mailman School of Public Health at Columbia University and president emeritus of Children’s Health Fund, is the author of “The Future of Us: What the Dreams of Children Mean for Twenty-First-Century America.”

Earlier this week, Ron Colburn, president of the Border Patrol Foundation, told the nodding hosts on “Fox & Friends” that pepper spray, one of the riot-control agents that U.S. Customs and Border Protection officials said they used over the weekend to deter migrants (including parents with young children in tow) was essentially benign. “It’s natural. You could actually put it on your nachos and eat it,” Colburn said. 

Setting aside the gross absurdity of Colburn’s statement, there are important concerns that cannot go understated. That Customs and Border Protection officers elected to deploy riot-control agents under circumstances that endangered the health — and perhaps the lives — of children was itself an unconscionable act that should never have been considered by agents of the U.S. government.

The fact is that children are uniquely susceptible to deployment of and exposure to riot-control agents such as tear gas and pepper spray. Here’s why:

First, respiratory rates in children are faster than that of adults. An infant, for instance, will take 30 to 60 breaths per minute, and a preschooler will take 22 to 34. Adults, on the other hand, average 12 to 16 breaths per minute. This means that relative to body weight, a child will inhale significantly more air in any given time frame — even more so under conditions of stress or panic. If that air is contaminated with tear gas or pepper spray, younger children will get a disproportionately large dose of the inhalable toxin. 

Second, these chemical agents can cause severe respiratory distress in people with preexisting pulmonary conditions such as asthma. This is of particular concern among Central American migrants, as a 2015 study by a multinational research group shows that asthma rates in Honduras and El Salvador are 18 percent and 24 percent, respectively (compared with about 10 percent in the United States). It’s reasonable to assume that a high percentage of the children in the caravan have asthma, and it’s important to note that an acute asthma attack in the absence of immediate medical care could easily be fatal.

Other than the respiratory impact of these chemicals, the direct effects of exposure in children include severe irritation and pain in the eyes, nasal passages and skin. Rapid inflammation and mucous in the respiratory system, including the trachea, can make breathing difficult, even if there is no preexisting chronic pulmonary precondition.

And remember: These children have been exposed to an arduous journey of many weeks traveling from Central America to the U.S. border. Families had limited access to food, shelter and rest. Uncertainty, danger and deprivation were constant companions throughout the trek.

In the days after the use of chemicals against migrants, many conservatives have painted the parents in the caravan as selfish — or worse — for attempting to bring their children to the United States. With no basis whatsoever, Homeland Security Secretary Kirstjen Nielsen even described the children as “human shields.”

I do agree that national borders need to be respected and asylum seekers need to be appropriately vetted. What’s needed, however, is serious immigration reform, not random acts of cruelty that can have terrible long-term consequences for children.

In reality, these people are fleeing from a desperate situation. Yes, for many it’s about economic opportunity that doesn’t exist in their home countries. But many, unprotected by corrupt and incompetent governments, are running from threats by vicious gangs. 

President Trump’s harsh rhetoric and aggressive policies at the border are both ineffective as deterrents and out of line with core American values. Last summer’s egregious zero-tolerance policies that separated nearly 3,000 children from their parents, for instance, were nothing short of officially sanctioned child abuse. Most of those children were deeply traumatized, especially so those who remain in detention facilities, still waiting for reunification with their parents.

And yet, migrants still under U.S. custody do not regret trying to get into the United States. I’ve spoken to dozens of detained migrant women, and every one of them said she would have attempted to cross the border even if she had known the conditions that she and her kids would face. That’s how terrifying the conditions are in their home countries.

Some defenders of the administration say the Obama administration used riot-control agents on migrants for years. But this only proves the point: Chemical agents have not and will not keep people from seeking asylum or opportunity in America.

There’s a lesson here for Trump. The administration has managed, once again, to traumatize kids and parents at the southern border — this time with tear gas and pepper spray. But we have not a shred of evidence that this cruelty will deter migration. Maybe a better approach would be to work upstream. Support the governments of Central America in definitive efforts to curtail corruption, eliminate the gang pipelines and create economic opportunity that every human being craves.