The Ziploc bags lawsuit, filed in April 2025 by California consumer Linda Cheslow, was voluntarily dismissed with prejudice in August 2025, meaning the claims cannot be refiled. The case alleged that S.C. Johnson’s “Microwave Safe” and freezer-use labeling concealed that the bags and containers shed microplastics and nanoplastics into food. The court never ruled on whether that was true; the plaintiff dropped the case before the judge decided S.C. Johnson’s motion to dismiss.
What the Lawsuit Claimed
Cheslow filed Cheslow v. S.C. Johnson & Son, Inc. on April 25, 2025, in the U.S. District Court for the Northern District of California under case number 3:25-cv-03655.1ClassAction.org. Cheslow v. S.C. Johnson and Son Inc., Complaint The complaint covered a wide slice of the Ziploc line: freezer bags in pint, quart, and gallon sizes, slider freezer and storage bags, and Ziploc containers.2ClassAction.org. Ziploc Lawsuit Claims Microwave Safe Storage Freezer Bags Containers Leach Microplastics Into Food
The core theory was a “Material Omission.” According to the complaint, Ziploc products are made from polyethylene and polypropylene, plastics that shed microplastics and nanoplastics when heated in a microwave or frozen, and the “Microwave Safe” and freezer-safe labeling created a false impression of safety by not disclosing that risk.1ClassAction.org. Cheslow v. S.C. Johnson and Son Inc., Complaint To support the science, Cheslow pointed to a 2023 study in Environmental Science & Technology reporting that some plastic containers released up to 4.22 million microplastic and 2.11 billion nanoplastic particles per square centimeter after three minutes of microwave heating.3American Chemical Society. Assessing the Release of Microplastics and Nanoplastics From Plastic Containers and Reusable Food Pouches The complaint also cited research linking ingested microplastics to potential harm to the digestive, immune, and reproductive systems.4NationofChange. New Lawsuit Claims Ziploc Brand Products Misleading, Increases Risk of Exposure to Microplastics
Cheslow brought four claims under California law: violations of the Unfair Competition Law, the False Advertising Law, the Consumers Legal Remedies Act, and unjust enrichment.1ClassAction.org. Cheslow v. S.C. Johnson and Son Inc., Complaint She sought federal jurisdiction under the Class Action Fairness Act, alleging a proposed class of more than 100 members and an amount in controversy above $5 million. The proposed class would have covered U.S. residents who bought the products for personal use during the statute of limitations period, with a four-year window for California buyers. The relief requested included an order barring S.C. Johnson from continuing the microwave-safe and freezer-safe advertising, restitution for the price premium consumers allegedly paid, and punitive penalties.5NBC Bay Area. Ziploc Lawsuit Undisclosed Microplastics
How S.C. Johnson Responded
S.C. Johnson denied the allegations. In a statement to USA Today, the company said it believes “Ziploc products are safe when used as directed and the claims in this lawsuit are without merit.”6Tyson & Mendes. Ziplock Bags the Plastic Canary in the Coal Mine The company said its products meet FDA safety requirements for the temperatures involved in defrosting and reheating food in microwaves, and for room, refrigerator, and freezer temperatures.7SC Johnson. Statement No Migration Dioxins From SC Johnson Plastic Products S.C. Johnson moved to dismiss on July 1, 2025.8PACER Monitor. Cheslow v. S.C. Johnson and Son Inc.
Why the Case Was Dismissed
Cheslow filed a stipulation of dismissal on August 19, 2025, and Judge William H. Orrick signed the order ending the case the next day.8PACER Monitor. Cheslow v. S.C. Johnson and Son Inc. The dismissal was voluntary and with prejudice, so the same claims cannot be brought again.9Mealey’s Litigation. Microplastic Leaching Suit Against Ziploc Maker Voluntarily Dismissed Because Cheslow dropped the case rather than litigate the motion to dismiss, the court never reached the scientific claims on the merits.
Coverage of the dismissal pointed to one central weakness: the complaint had no product-specific testing. It relied on general research about polyethylene and polypropylene and on studies of other brands’ containers, rather than data showing that Ziploc products themselves released microplastics at harmful levels under the conditions of use printed on the packaging.10Lawsuits Journal. Ziploc Lawsuit
What the Dismissal Does and Doesn’t Settle
The outcome closes Cheslow’s case, but it is not a court finding that Ziploc products are safe or unsafe. No judge weighed the evidence.
The regulatory picture is what it was before the suit. The FDA states that “current scientific evidence does not demonstrate that levels of microplastics or nanoplastics detected in foods pose a risk to human health” and that there is “not sufficient scientific evidence to show that microplastics and nanoplastics from plastic food packaging migrate into foods and beverages.”11U.S. Food and Drug Administration. Microplastics and Nanoplastics in Foods The FDA has not issued specific rules for microwave use of food packaging, though food-contact materials must be suitable for their intended conditions of use under its general requirements.12PackagingLaw.com. What Are FDAs Regulations Food Packaging and Microwave Use
The underlying research is still developing. The 2023 University of Nebraska study found that microwaving certain containers released billions of nanoplastic particles and that 77% of cultured kidney cells died after exposure to those particles in laboratory conditions.13University of Nebraska-Lincoln. Nebraska Study Finds Billions of Nanoplastics Released When Microwaving In October 2025, the European Food Safety Authority acknowledged that micro- and nanoplastics are released from food-contact materials during normal use but concluded there is still no sufficient basis to estimate human exposure levels from such use.14Food Packaging Forum. EFSA Publishes Report on Micro and Nanoplastics From FCMs A June 2025 systematic review in Nature identified food-contact articles as a confirmed source of microplastics but noted that only seven of the 103 studies it examined were “highly reliable,” and current regulations do not require microplastic migration testing for food packaging.15Nature. Assessing the Release of Microplastics and Nanoplastics From Food Contact Articles
The gap between concerning laboratory findings on plastics in general and the absence of Ziploc-specific data or a regulatory standard is where the case fell short. Without testing tying Ziploc products to unsafe migration levels, the general science was not enough to carry the claims.
The Canadian Case
A parallel class action was filed in Quebec on May 26, 2025, by the law firm Lambert Avocats against S.C. Johnson & Sons, Limited in the Superior Court of Quebec, case number 500-06-001380-258. It raised similar microplastic-release allegations. On September 29, 2025, the Quebec court authorized the withdrawal of the application. The plaintiff acknowledged that the scientific evidence did not support the microplastic-release allegations and that S.C. Johnson had implemented measures ensuring product safety for their intended uses. The withdrawal specifically cited the Cheslow dismissal as confirming the insufficiency of the claims’ scientific basis.16Lambert Avocats. Class Action Ziploc As in the U.S., the court did not reach the merits; the case was pulled before certification.