Avoid burning or heating film at home; that can create unpleasant or potentially hazardous fumes and isn’t necessary.

Practical options mentioned were:

1. Bleach: Ordinary household bleach can destroy the image because the picture is held in a thin gelatin emulsion layer. Bleach can lift/separate that emulsion from the film base, making the image unreadable.

2. Secure shredding: A basic paper strip shredder is usually not enough. For film, you want very small particles—look for a shredder meeting DIN 66399 F-2 or higher (roughly similar cut size to P-5 paper security), so the pieces are too small to reconstruct usefully. A secure document/data destruction service may also handle this.

3. Blender/food processor dedicated to the task: An old thrift-store blender can chop film into tiny pieces. Don’t use one you plan to use for food afterward.

If using a home shredder, running the pieces through multiple times can help, though there’s a limit to how small they’ll get.

For safety and simplicity, the best home methods are bleach or mechanical destruction into very small pieces.