Cadbury's US business has been hit by an unusual lawsuit from three of the company's taste testers who claim to have been seriously injured trying a new product.

The three testers, all women from Morris County in New Jersey, accuse Cadbury Adams of exacerbating their injuries, which they sustained in spring, by delaying the disclosure to a dentist of the ingredients in the offending sample.

The women themselves still do not know the make-up of the sweetener according to Robyne D LaGrotta, their lawyer.

According to their lawsuits, Maureen Zuccarini, of Parsippany, New Jersey, felt her mouth burning and had injuries to her tongue as she took receipt of the additive. Stefanie Bonfiglio, of Whippany, New Jersey, says that she felt burning in her mouth and lower gum, as her lip swelled up and her heart raced.

Donna Magliaro, of Denville, New Jersey, reported a reaction on her lower lip and an irregular heartbeat.

The women claim that their employer's conduct has resulted in permanent injuries and claim that it failed to maintain a safe workplace, as required by New Jersey law.

Ms LaGrotta claims Ms Magliaro was sacked after suffering her injuries after being “told she was asking questions and making others uncomfortable”.

The other two testers then quit, she added, because “they no longer felt safe doing this”. Ms LaGrotta added: “The company disclosed they had reactions, which is protected health information, and they were viewed by others as troublemakers.”

The three women are seeking unspecified monetary damages for medical expenses and suffering.

They have also sued Spherion Atlantic Enterprises, the agency which hired them to work at Cadbury Adams for $10 (£5) an hour.

A spokeswoman for Spherion said: “We take these allegations very seriously and are conducting a thorough investigation.”

A spokeswoman for Cadbury Adams said: “We take the health and safety of our colleagues very, very seriously and are sorry if they experienced any adverse reaction.

"We have not yet been served the papers but when we are, we will review them very carefully and take the appropriate action.”

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