Ellen Richardson went to Pearson airport on Monday full of joy about flying to New York City and from there going on a 10-day Caribbean cruise for which she’d paid about $6,000.

But a U.S. Customs and Border Protection agent with the Department of Homeland Security killed that dream when he denied her entry.

“I was turned away, I was told, because I had a hospitalization in the summer of 2012 for clinical depression,’’ said Richardson, who is a paraplegic and set up her cruise in collaboration with a March of Dimes group of about 12 others.

More than a dozen Canadians have told the Psychiatric Patient Advocate Office in Toronto within the past year that they were blocked from entering the United States after their records of mental illness were shared with the U.S. Department of Homeland Security.

Lois Kamenitz, 65, of Toronto contacted the office last fall, after U.S. customs officials at Pearson International Airport prevented her from boarding a flight to Los Angeles on the basis of her suicide attempt four years earlier.

Kamenitz says she was stopped at customs after showing her passport and asked to go to a secondary screening. There, a Customs and Border Protection officer told Kamenitz that he had information that police had attended her home in 2006.

Kamenitz was eventually allowed to board a plane to Los Angeles, four days after missing her initial flight. But in order to do so, she had to submit her medical records to the U.S. and get clearance from a Homeland Security-approved doctor in Toronto, who charged her $250 for the service.

Benson says the response from the U.S. Customs and Border Patrol officers in Kamenitz's case was fairly typical. "Now that the note from her doctor is on her records," he says, "I wouldn't expect her to have any more problems."

Included in the Homeland Security forms Kamenitz was required to fill out were questions about whether she had a history of substance abuse and whether she had diseases, such as AIDS or tuberculosis.

"These are private and personal medical records that I’m now handing over to a foreign government," she says.

Brad Benson from the U.S. Department of Homeland Security says medical records aren't shared between countries. However, "if you have an arrest record, Canada would share that with us," he says.

If a police encounter includes information about mental health, Benson says front-line officers can use it.

"Mental illness is actually under our law as a reason that you may not get admitted," he says. "The issue is always going to be: could someone be a danger to someone [else]?"