Thomas Dixon tours the strange theories on tears proposed over the years:
[T]here is a traditional Yiddish phrase for crying that translates literally as ‘pissing from the eyes’. This old idea has been reinforced by modern science in the last century and a half. In recent decades, the most widely quoted theorist of tears has been the American biochemist William H Frey II who, since the 1980s, has been arguing that the metaphor of weeping as excretion should be taken quite literally. In an interview with The New York Times in 1982, Frey claimed that crying is ‘an exocrine process’ which, ‘like exhaling, urinating, defecating and sweating’ releases toxic substances from the body — in this case, so-called ‘stress hormones’.
It gets weirder:
In a couple of articles in the 1940s, the influential American Freudian Phyllis Greenacre put forward the view that neurotic weeping in women was to be understood as a displacement of urination. Involved in this theory was the idea of ‘body-phallus identification’ and the production of tears by women as an attempt to simulate male urination.