A new report estimates at least 2.2 million children had been affected by the opioid crisis in the United States by 2017.

That number is likely to increase, according to the report by the United Hospital Fund, a health policy nonprofit. Many of the children are living with a parent addicted to opioids or have been removed from their home, according to U.S. News & World Report. The report found 170,000 children had opioid use disorder themselves, or had accidentally ingested opioids.

There could be 4.3 million children affected by the opioid crisis by 2030, at a cost of $400 billion, the report estimated.

“This report shines a light on a population affected by opioids that is often hidden from view,” study co-author Suzanne Brundage said in a news release. “But these estimates should not cause despair. Instead, they highlight the urgent need to take action now to help these children and their families.”