ORLANDO, Fla. — The multimillion-dollar Florida medical marijuana industry is flourishing, with new dispensaries opening at a rapid pace. But one fundamental challenge has emerged: Where to put the cash?

• Florida now has 212,000 registered medical marijuana users
• Financial institutions are afraid they'll lose insurance protections
• State officials pushing Congress, White House for "safe harbor"

For all intents and purposes, the medical marijuana industry in Florida — which now has 212,000 registered users — is considered an “all cash” business, and it faces growing difficulty to hold that cash in traditional bank and credit union accounts.

“Banks are afraid to deposit money, because they have a fiduciary responsibly to take care of their accounts,” state Chief Financial Officer Jimmy Patronis said.

The issue at hand is that although Florida may allow medical marijuana, it is still an illicit drug in the eyes of the federal government. So most banks and credit unions fear they could lose federal insurance protections carried on individual accounts if they accept "illegal" drug money.

“The idea is that any money derived from drug business is really fruit of the poisonous tree. You can’t touch it,” said Jared Ross, senior vice president of the League of Southeastern Credit Unions.

It is for these similar reasons that then-Agriculture Commissioner candidate Nikki Fried said that multiple campaign accounts were shut down by banks, because her campaign accepted donations from medical marijuana companies.

Jeff Sharkey, founder of the Medical Marijuana Business Association of Florida, said his group was notified by SunTrust that its accounts would also be shut down for receiving money from the marijuana industry.

“The real challenge has been on the banking side,” Sharkey said. “Most banks today are not willing to spend the time, energy, and money, because it’s expensive to do, (to) take the risk... or (risk) the potential (that) it may not be in compliance over something. That’s been the challenge.”

There have been various efforts at the state and federal levels to create protections for the banking industry to allow it to expand access to medical marijuana companies.

Patronis said he's made multiple pleas to the White House, asking President Donald Trump sign an order granting Florida "safe harbor."

"The White House has already said, ‘We got your letter; we’re working on a response,' " Patronis said. "Seventy percent of Florida voters voted for it, but it’s moving the needle in how it’s scheduled."

U.S. Rep. Darren Soto (D-Kissimmee) is moving a measure through Congress called the Safe Banking Act.

“This bill would give safe harbor to these banks and give safe harbor to these business and accounts if they are legal under state law,” Soto said. “This is about state rights, this is about respecting the voters, and it’s really about eliminating a potential for crimes to happen, because when you have an all-cash business, you can have problems."

Both Soto and Patronis have expressed concern about crimes that could range from robbery to money laundering in an all-cash business.

The medical-marijuana companies, for their part, say they have taken extreme measures to ensure security in their operations.

While customers must pay for prescriptions using cash, some of the major dispensary companies operating in Florida have come up with short-term workarounds. Curaleaf, for example, has accounts with Denver-based Partner Colorado Credit Union, which has a safe harbor cannabis banking program.

Curaleaf and Knox parent-company Cansortium, Inc., also rely on apps such as CanPay, which touts itself as the world’s first debit payment app for cannabis retailers.

The issue of the companies not being able to hold accounts with financial institutions will likely only change with an act of Congress or a presidential approval providing safe harbor.