“I’m about to have a cup of dangerous coffee. Safe tea first though”

“Safety first” is a slogan that has been used since the early 1900s. “Safe-Tea First” is a pun that was used in Ridgways Tea advertisments from October 1914.
 
A jocular saying was posted on Twitter on July 16, 2011:
 
“I’m about to have a cup of dangerous coffee. Safe tea first though.”
   
 
30 October 1914, San Francisco (CA) Chronicle, pg. 3, col. 5 ad:
SAFE-TEA FIRST
DRINK
Ridgways Tea
 
Chronicling America
12 December 1914, Richmond (VA) Times-Dispatch, pg. 7, col. 6 ad:
SAFE-TEA FIRST
DRINK
Ridgways Tea
 
Google Books
May 1915, Country Life in America, pg. 33, col. 2 ad:
“SAFE-TEA” FIRST
Ridgways Tea
 
Twitter
Eoin Rogers
‏@erogers89
@PaulieCummins I’m about to have a cup of dangerous coffee.Safe tea first though.
6:39 PM - 16 Jul 2011
 
Twitter
PAULIEBOY#IHOW
‏@PaulieboyIHOW
I’m about to have a cup of dangerous coffee.Safe tea first though.
7:42 PM - 16 Jul 2011
 
Twitter
Rich H
‏@Stamford_Grinch
I’m about to have a cup of dangerous coffee.Safe tea first though.
2:09 AM - 17 Jul 2011 from Bexley, England
   
18 July 2011, The Sun (London, UK), pg. 20:
I’M about to have some dangerous coffee. Safe tea first though.
 
Google Books
5,000 Great One Liners
Compiled by Grant Tucker
London: Biteback Publishing
2012
Pg. ?:
I’m about to have a cup of dangerous coffee. Safe tea first though.
   
Twitter
Bad Joke Cat
‏@BadJokeCat
I’m about to have a cup of dangerous coffee. Safe tea first though.
5:03 PM - 29 Sep 2014
 
Twitter
Shit Jokes
‏@ShitJokes
I’m about to have a cup of dangerous coffee.
Safe tea first though.
1:26 PM - 24 Jan 2016