Барбитуру ты у нас у любой бабки за 70 найдешь, комбинированные препараты фенобарбитала у нас без рецепта отпускают.

Ну это вроде не частое явление, да, но тут кое-кто это подтверждал.
https://www.reddit.com/r/canada/comments/1sc6zc/this_is_what_happens_to_a_20_dollar_bill_at_30/

"I've had a number of bills snap in half. I left my wallet in my car at -36 last winter, opened it up, and had to bring 6 half bills into the bank to swap out.
The new plastic money is hilariously not designed for Canadian weather."

"A friend in Calgary had this in his jacket pocket while outside. The bill got very stiff in the cold and that corner broke off. The bills are not made of Tyvek, it is a proprietary polymer made just for currency."

Не факт, что для России подойдут. Канадский опыт говорит, что на морозе они могут трескаться.