Gemini VII still has the record!
The Gemini 7 mission in 1965 set a record for long-duration flight aboard a capsule, in which astronauts Frank Borman and James Lovell spent just short of 14 days in Earth orbit in a tin can with roughly the interior dimensions of a SMART PlusTwo, and no toilet. They were investigating the human body's ability to withstand spaceflight for the duration of an Apollo mission to the moon and back.
... The sanitary arrangements were crude, to say the least.
NASA are cagey about the precise details, but it's rumoured that Lovell and Borman went almost six days before one of them cracked and broke out the "defecation kit", which was basically a plastic bag the astronaut had to tape to their ass before taking a dump. They then had to use a finger cot -- basically a finger-sized condom -- to scrape any cling-ons into the bag, break a capsule of disinfectant inside it, and mix the contents thoroughly before storing it under the seat. And that's the system all the Apollo missions used.
Biting the hand that feeds IT
