[6][5] Noticing that there were six pills missing, she turned the bottle over to investigator Nick Pishos and reported her suspicion that it was related to the Janus' deaths.
[7] A multi-agency investigation found the tampered pills to have been sold or on the shelves at a variety of stores in the Chicago area, including two different Jewel Foods locations (one in Arlington Heights, one in Elk Grove Village); an Osco Drug store (in Schaumburg); a Walgreens and a Dominick's (both in Chicago); and a Frank's Finer Foods (in Winfield).
[12] The company also advertised in the national media for individuals not to consume any of its products that contained acetaminophen after it was determined that only these capsules had been tampered with.
[2] In early 1983, at the FBI's request, Chicago Tribune columnist Bob Greene published the address and grave location of the first and youngest victim, Mary Kellerman.
The story, written with the Kellerman family's consent, was proposed by FBI criminal analyst John Douglas on the theory that the perpetrator might visit the house or gravesite if they were made aware of their locations.
Upon his arrest, Lewis told authorities how the person behind the attacks may have carried out the killings—by buying Tylenol, adding cyanide to the bottles, and returning them to the store shelves.
[18] Lewis was also found to have previously possessed a poisoning book, and, according to a confidential law-enforcement document, his fingerprints were discovered on pages related to cyanide.
[19] Court documents released in early 2009 "show Department of Justice investigators concluded Lewis was responsible for the poisonings, despite the fact that they did not have enough evidence to charge him".
[26] Police also investigated a second man, Roger Arnold, a dock worker at a Jewel-Osco in Melrose Park, who told officers that he possessed potassium cyanide.
[28] A copy of The Poor Man's James Bond, which contained instructions on making potassium cyanide, was found in Arnold's home.
In a written statement,[35] the FBI explained, This review was prompted, in part, by the recent 25th anniversary of this crime and the resulting publicity.
[37] Hundreds of copycat attacks involving Tylenol, other over-the-counter medications, and other products also took place around the United States immediately following the Chicago deaths.
[42] That same year, Procter & Gamble's Encaprin was recalled after a spiking hoax in Chicago and Detroit that resulted in a precipitous sales drop and a withdrawal of the pain reliever from the market.
[43] In 1991 in Washington state, Kathleen Daneker and Stanley McWhorter were killed from two cyanide-tainted boxes of Sudafed, and Jennifer Meling went into a coma from a similar poisoning but recovered shortly thereafter.
[49] In addition to issuing the recall, the company established relations with the Chicago Police Department, the FBI, and the Food and Drug Administration.
[52] McNeil sued again in court, further contending that the language of its excess liability insurance policy covered the recall and recall-related expenses.
[55] The 1982 incident inspired the pharmaceutical, food, and consumer product industries to develop tamper-resistant packaging, such as induction seals and improved quality control methods.
[56] The new laws resulted in Stella Nickell's conviction in the Excedrin tampering case, for which she was sentenced to 90 years in prison.
[42] Additionally, the incident prompted the pharmaceutical industry to move away from capsules, which were easy to contaminate as a foreign substance could be placed inside without obvious signs of tampering.
[2] While poisoned candy being given to trick-or-treaters at Halloween is rare, the Tylenol incident, which unfolded across October 1982, raised renewed fears of it.