(Reuters) - A federal appeals court on Monday handed manufacturing groups a victory by ruling that a consumer-safety commission "procedurally erred" when passing a rule that prohibits children's toys containing too much of a type of chemical used to make plastics.

A unanimous three-judge panel of the 5th U.S. Circuit Court of Appeals remanded to the U.S. Consumer Product Safety Commission (CPSC) its rule prohibiting the manufacturing and sale of children's toys and care articles containing concentrations of five types of phthalates exceeding 0.1%. The panel agreed with the plaintiffs, including the National Association of Manufacturers (NAM), that the agency failed to give the public an adequate chance to comment on the rulemaking after it changed its scientific justification for the regulation from data organized in percentiles to another methodology, namely randomly collected data.

CPSC spokeswoman Karla Crosswhite-Chigbue said the agency declined to comment. The Department of Justice declined to comment, said its spokeswoman Gail Montenegro.

Neither NAM nor the plaintiffs' attorneys at Baker Botts immediately responded to requests for comment.

Phthalates are a family of chemical compounds. Some phthalates can suppress the production of testosterone and normal mental and physical development, the ruling says.

Writing for the panel, Chief U.S. Circuit Judge Priscilla Owen agreed with the manufacturers that when CPSC issued its final rule in 2017, it didn't carry out the Administrative Procedure Act's notice-and-comment procedure.

The judge said that, when the agency changed the data it relied on to justify the rule, it failed to clearly invite comments on its use of the newer data to supplant the older, "statistically unstable" one.

The judge was joined by U.S. Circuit Judges Leslie Southwick and Stephen Higginson.

The case is Texas Association of Manufacturers v. CPSC, 5th U.S. Circuit Court of Appeals, No. 17-60836.

For Texas Association of Manufacturers: Aaron Street of Baker Botts

For CPSC: Scott McIntosh, U.S. Department of Justice