The products, marketed by Spin Master Ltd. of Toronto, sold for $17 to $30 and were available at stores including Toys "R" Us, Wal-Mart Stores Inc. and Target Corp. from April through this month, the Consumer Product Safety Commission said late Wednesday.

A coating on the beads that causes them to stick to each other when water is added contains a chemical that can turn toxic when many are ingested, the agency said.

"Children who swallow the beads can become comatose, develop respiratory depression or have seizures," it said.

The agency said it received two reports of children swallowing Aqua Dots.

A 20-month-old child who swallowed several dozen beads became dizzy and vomited several times before slipping into "a comatose state," the agency said. He was hospitalized and has since fully recovered.

A second child also vomited and slipped into a comatose state and was hospitalized for five days before recovering, the agency said.

Consumers should immediately take the recalled toy away from children and contact Spin Master to return it for free replacement beads or a toy of equal value, the agency said.

For more information, contact Spin Master at (800) 622-8339 between 9 a.m. and 6 p.m. EST Monday through Friday or visit the firm’s Web site at www.aquadotsrecall.com.