CHICAGO, May 5 (Reuters) - Tyson Foods ( TSN ) has been

"proactively reformulating" food products containing

petroleum-based synthetic dyes and plans to finish work to

eliminate them from its production process by the end of May,

CEO Donnie King said on Monday.

Most of the meat company's retail-branded products,

including Tyson chicken nuggets, do not contain those types of

dyes, King said on an earnings call.

U.S. Health Secretary Robert F. Kennedy Jr. and FDA

Commissioner Marty Makary said last month that the agency plans

to remove synthetic food dyes from the U.S. food supply by

revoking authorizations of some and working with the industry to

voluntarily remove others.

Kennedy said that the efforts to remove additives from

food were necessary to address chronic diseases in children and,

without evidence, suggested that it would address rising rates

of conditions ranging from ADHD to food allergies.

No products that Tyson offers in school nutrition

programs include petroleum-based synthetic dyes, King said.