More packages of frozen shrimp potentially affected by radioactive contamination have been recalled, federal officials said last week.

California-based Southwind Foods recalled frozen shrimp sold under the brands Sand Bar, Arctic Shores, Best Yet, Great American and First Street. The bagged products were distributed between July 17 and Aug. 8 to stores and wholesalers in nine states: Alabama, Arizona, California, Massachusetts, Minnesota, Pennsylvania, Utah, Virginia and Washington.

The products have the potential to be contaminated with Cesium-137, a radioactive isotope that is a byproduct of nuclear reactions.

Walmart last week recalled packages of Great Value frozen raw shrimp sold in 13 states because of potential radioactive contamination.

The U.S. Food and Drug Administration issued a safety alert after federal officials detected Cesium-137 in shipping containers sent to four American ports and in a sample of frozen breaded shrimp imported by BMS Foods of Indonesia.

The FDA advises consumers not to eat the recalled products.  The primary health risk is through long-term, repeated low-dose exposure, which can increase the risk of cancer.