To test the validity of these categories, ProPublica paid $30 to digitally pander to them with three "Promoted Posts".
The advertisements were purchased through its self-service tool, which allows buyers to independently purchase and target ads, often without human interaction on Facebook's side of the transaction.
Facebook addressed the issue in an interview with Bloomberg, stating that it is "removing these self-reported targeting fields until we have the right processes in place to help prevent this issue".
Facebooksaid last week an operation based in Russian Federation spent $100,000 (€84,000) on thousands of United States ads promoting social and political messages over a two-year period through May, fuelling concerns about foreign meddling in USA elections.
The categories were available to advertisers buying ads through the firm's self-service function, and journalists were able to use the system to target almost 2,300 users who had previously searched by such terms and phrases.
Jonathan Greenblatt, CEO of the Anti-Defamation League, commended Facebook for taking action but said he'd follow up with the social network.
In ProPublica's investigation, 2,274 people fell under the "Jew hater" demographic, while other categories included "German Schutzstaffel", "NaziParty", and "Hitler did nothing wrong".
The data informing the advertising categories on Facebook was generated automatically, said the ProPublica reporters, and was created from content people explicitly shared on the site as well as by what they revealed via their activity. It is also considering adding an extra review step to make sure interests that amount to hate speech don't make it onto the ad platform. The Jewish community has been raising concerns for years about reporting that celebrates the Holocaust, claims that Jews rule the economy, and evoking blood libel, and receiving back notifications that such content "doesn't violate our community standards".
He said it was building "guardrails" into its processes to stop offensive self-reported profile traits being used as ad categories.
Because targeted ads are not sold for such small groups, the automated system suggested the category "Second Amendment" - the right under the US Constitution to bear arms - as an additional category.
Facebook removed controversial topics from its ad system following the report from ProPublica.
The problem occurred because people were listing "jew hater" and the like in their "field of study" category, which is of course a good one for guessing what a person might be interested in: meteorology, social sciences, etc.
Facebook has a lot "more work to do" indeed, because a follow-up investigation by Slate shows that its algorithm also recognizes "Kill Muslimic Radicals" and "Ku-Klux-Klan" as valid ad categories.