With baby products, try to avoid plastics that contain toxic chemicals, like Bisphenol-A(BPA) and phthalates. Plastic #4 is low-density polyethylene or LDPE, and it's your safest bet, while plastic #3 is polyvinyl chloride (PVC). It's widely used because it's cheap, durable, and easy to assemble. PVC is less safe because it's made with vinyl chloride, which is cancer-causing. It also poses serious environmental and health threats at all stages of its lifecycle - from manufacturing to use to disposal.

The good news is that safer and cost-effective alternatives are already available for virtually every PVC product out there, including baby products. ( Source)

Here's a great spreadsheet with information on the more readily available brands and how they stack up from an environmental standpoint.

Go here: Diaper Graph.

Here's a couple other baby supply recipes from the Queen of Green: