Pediatricians are warning that a federal policy separating parents and children at the U.S.-Mexico border poses serious long-term health issues for children. In some cases, they say, the separation could cause “irreparable harm.”

Efren Olivares, director of the Racial Economic Justice Program at the Texas Civil Rights Project, says dozens of people are coming into the U.S. through the Texas border, in particular, without documentation. In many of those cases, he says, their children are promptly being taken away before officials determine whether they qualify for asylum.

“Before any of that is decided, their children are being taken away without the parent being informed of where the children are going, where they may see them again, and what the conditions are being detained in,” Olivares told reporters during a conference call last week.

Health care advocates say this practice, which has been going on for months, will likely result in lasting health issues. Dr. Nadine Burke Harris, the CEO and founder of the Center for Youth Wellness, says the policy is "a recipe for toxic stress."

"When kids are going through stressful situations, being kept together with their parents or their caregivers is actually critically important to prevent these long-term health problems," she says.

Harris says toxic stress is the result of the "absence of a buffering caregiver who can help the child be able to regulate their stress response." That can take an emotional and physical toll on a child.

"We are talking about double the risk for asthma," she says. "We are talking about increase risk of learning and developmental problems, increase risk for infections, autoimmune disease. And over the long term, we are talking about increase risk of heart disease, stroke, cancer, Alzheimer’s, mental health issues – all kinds of health conditions."

Besides the toll this takes on the individual child, Harris says, this policy comes with a considerable public health cost.

The American Academy of Pediatrics released a statement last month warning about the effects of stress on those children, some of whom are very young.

“In fact, highly stressful experiences, like family separation, can cause irreparable harm, disrupting a child's brain architecture and affecting his or her short- and long-term health,” says Dr. Colleen Kraft, the group's president.

KUT's Ashley Lopez reports

In an article in The New England Journal of Medicine published in June 2017, physicians warned about the possible health effects of the Trump administration’s then-proposed policy to separate families.

“If children are unnecessarily and traumatically removed from their parents, their physical and mental health and well-being will suffer,” authors of the article wrote. “The effects of traumatic experiences — especially in children who have already faced serious adversity — are unlikely to be short lived: cumulative adversity can last a lifetime, even increasing the risk of early death.”

The Trump administration has said the policy is aimed at deterring people from entering the U.S. without documentation. In the meantime, officials are sending those children to live with other families.

“The children will be taken care of — put into foster care or whatever," President Trump's chief of staff, Gen. John Kelly, told NPR last month. "But the big point is they elected to come illegally into the United States and this is a technique that no one hopes will be used extensively or for very long."

Harris says, however, that sending those children to live with strangers will not "mitigate the damage of being separated from their parent or caregiver."

"That strongest bond is between parent and child," she says. "There is no replacement for that healthy bond between parent and child."