HOWELL, Mich. (AP) — The maker of Pepsi is encouraging customers to return certain 16.9-ounce bottles of Pepsi-Cola that were sold in Michigan earlier this year.

Pepsico says there’s no safety issue. But the company says it received 18 complaints of a metallic taste, from late February to early April.

An investigation found minute particles of iron and chromium in bottles due to a parts failure in the manufacturing process. In March, Pepsico removed the cola from nearly 200 Michigan stores. Other Pepsi products are not affected.

Pepsico says bottles with product codes HC022373 and HC022473 should be returned to stores. Anyone with questions can call (866) 433-2652.