sacramento (ap) | A rented donor list used by several charities mistakenly inserted recipients’ religious affiliations into their mailing addresses on envelopes, offending many of the recipients.

One fund-raising letter, from the Alliance for Retired Americans, was addressed to “Herbert Kaiser, Jewish.”

Kaiser, a World War II veteran who lives in Palo Alto, said seeing his religious designation on the envelope reminded him of past labels forced on Jews. “That’s the first thing that popped into my mind when I got that letter,” he told The New York Times. His complaint was first reported in The Washington Post.

The error was traced to a list of donors rented from the California-based United Farm Workers.

“We feel very badly about it,” UFW spokesman Marc Grossman told The Associated Press. “It’s unclear how many people were affected by it, but even if it was one that was offended — that’s too many.”

The UFW sent its donor database to Triplex, a data management and collection company that breaks down information so mailing lists can be shared with other companies and nonprofits. The database included designations such as “Catholic” and “Hindu.”

“Without those breakdowns, many other organizations would not be interested in exchanging or renting our list,” Grossman told the Times. “Jewish groups want to send mail to Jewish donors. Catholic groups want to send to Catholics.”

But he said the UFW has not done a mailing based on religion. “If we did, we certainly wouldn’t place such religious information on the address label,” he said.

Grossman said the union received a Dec. 10 e-mail message from Triplex, in which a company employee wrote that the database’s religious code was mistakenly moved into a field normally used for business names.

“We’ll take the blame for quality control, because we should have checked the mail before it went out, but we’re not the provider of the data,” said Fred Vakili, chief administrative officer of infoUSA, Triplex’s owner.