A sticky story on the glue you lick to seal envelopes

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

There is an interesting article by Joe Schwarcz at the McGill Office for Science and Society on March 26, 2025 titled A Sticky Story. He states that:

 

“The adhesives that are used on envelopes and stamps have very stringent safety requirements. That shouldn’t be surprising. After all, some of the stuff may be swallowed, so it has to be regulated as a food. Gum arabic from the acacia tree, dextrin from corn starch and the water-soluble resin, polyvinyl alcohol are the adhesives most commonly used. There are also additives for flexibility and spreading quality which include glycerin, corn syrup, various glycols, urea, sodium silicate and emulsified waxes. Preservatives such as sodium benzoate, quaternary ammonium compounds and phenols are also included. These substances may not taste great, but they are not poisons.”

 

The final episode from the 1995 season of Seinfeld titled The Invitations is not realistic:

 

“Disregarding George's suggestion to use glue for the wedding invitations since the adhesive in the envelopes takes a lot of moisture to work, Susan keeps licking envelopes until she passes out. George returns to his apartment, finds that Susan has collapsed, and takes her to the hospital. After the examination, a doctor informs George that Susan is dead from licking the envelopes, since the adhesive is toxic.”