Compostable plastic packaging and foodware is commonly marketed as a more eco-friendly alternative to conventional plastic. It's used for single-use utensils, straws, bin liners, takeout containers, and cups, and is made from renewable sources like sugar cane and corn as well as fossil fuels.

While designed to break down into carbon dioxide and water under specific conditions, growing research shows that compostable plastics often don't break down as advertised and pose real risks to soil health, public health, and our waste management system. The proliferation of this material is undermining California's climate and environmental goals, misleading consumers, and placing undue burdens on composters, local governments, and businesses.

The Problem with "Compostable Plastics"

They often don't get composted — and can prevent food scraps from being composted too

Just because a product is labeled "compostable" doesn't mean it actually gets composted. Most compost facilities can't tell compostable from conventional plastic, so they remove both.

  • Composters remove any plastic-like material manually or with equipment if available.
  • Compostable bags are often opaque, making it difficult to identify the contents. They're frequently removed with food scraps still inside, sending both to landfill.
  • Removed compostable plastics end up in the landfill, where they release methane — a harmful greenhouse gas.
  • While compostable plastics might help get more food scraps into the green bin, they often don't result in more material actually being made into compost.

They leave microplastic pollution in soil

When compostable plastics are sent to commercial compost facilities, they don't always fully degrade. Increasing research finds they leave behind microplastics — tiny plastic particles that linger in soil for years and can enter our food system and waterways.

  • These microplastics are too small to screen out of finished compost and contaminate soil, water, and food.
  • Research shows compostable microplastics can be just as harmful — or worse — than conventional microplastics. Toxic additives used to make compostable products function effectively remain in the fragments.
  • Even "certified compostable" standards only require 90% biodegradation, leaving unwanted small plastics in finished compost.
  • Farmers use compost as a soil amendment to grow food and don't want microplastics of any kind in the final product.

They perpetuate "throw-away" culture

Switching from conventional to compostable plastic doesn't solve the bigger problem: our single-use culture.

  • Like their traditional counterparts, compostable plastic items can still become litter in waterways and oceans where they do not decompose.
  • Whether made from plants or petroleum, all compostable plastic items have an environmental cost — from farming and manufacturing to transporting and disposal.
  • Replacing one disposable product with another doesn't reduce waste — it just changes the material.
  • Single-use is still single-use, no matter what it's made of.

They cost more and don't work well

Compostable plastic products are often more expensive than conventional ones — and less effective.

  • A case of 1,000 compostable cups can cost 2–3 times more than standard disposable cups.
  • Compostable bin liners tend to leak or break, requiring extra cleanup and additional liners.
  • Marketing often persuades consumers they need compostable bags for food scraps, even though these bags create challenges for compost facilities and can result in food scraps being sent to landfill.

A Better Path Forward

The best solution is upstream — avoiding single-use disposables of any kind and opting for reusables whenever possible to reduce plastic pollution, prevent soil contamination, and protect health.

For Residents

  • Dine in when you can — it almost always generates less waste. When ordering takeout, opt out of items you already have, like napkins, utensils, and straws.
  • For parties and gatherings, use reusable plates, cups, and utensils. If reusables aren't an option, choose unlined paper products, which can be composted.
  • Recyclable foodware can work too, especially when containers stay clean. Plastic cups labeled #1, #2, or #5 are recyclable in most California cities. Check your city here.
  • Collect food scraps without a compostable bag — use a bowl, paper bag, or cardboard box. The soiled paper bag or box can go in the green bin with your food scraps. For kitchen pail liners, try a paper towel, newspaper, or none at all and toss scraps directly into your curbside bin. Liners are not mandatory for food scrap collection.
  • For pet waste, use conventional plastic bags and put it in the garbage. Animal waste should never go in the green bin.

For Businesses

  • Provide reusable foodware for on-site dining. Replacing disposable foodware with reusables reduces costs, saves resources, and prevents litter.
  • Encourage customers to bring their own reusable cups and containers. It's safe and allowed by the health code.
  • When disposables are necessary, opt for natural fiber or paper options for plates, utensils, cups, bowls, and straws. Paper and wood products can be composted — just make sure items are not lined with plastic.
  • For bin liners, paper bags work for indoor bins, and many cities allow clear plastic bags (leave them untied so the compost facility can empty and remove the bag).
  • Recyclable foodware is also an option when containers stay relatively clean. Plastic cups labeled #1, #2, or #5 are recyclable in most California cities. Check your city here.

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