The chemical properties of shower gel are a closely guarded secret, not normally revealed by manufacturers. Obviously its sticky, glue-like qualities are what makes it so useful. Although some artificial gel products are on the market, the best selling products are still entirely natural. Vast forests of sap producing trees are maintained on gel farms, for producing the large amounts of shower gel sold worldwide. Sap extracting robots have been developed to speed production.
Retail prices vary widely, but the industry is considered to be quite profitable.
As far as safety goes, the product has had virtually no problems since gaining widespread popularity worldwide at the start of the 20th century. The only incident worth recalling was the case in 1937 of the woman in New Hampshire, USA, who placed a large amount of gel over her closed eyes, and left it there after finishing her shower. She left it on for 30 minutes, and it set, leaving her temporarily blinded until it could be removed using cutting equipment. I trust this information proves useful, and thanks again for allowing me to write to you concerning a subject about which I know nothing at all. I await her reply with interest.