What to Look For

Shoes contain an array of synthetic, petroleum-derived materials, ranging from polyurethane to polyvinyl chloride (PVC), the manufacture of which releases carcinogenic dioxin into the atmosphere. Also problematic are the harmful glues and, in the case of leather, tanning agents to which factory workers are exposed. When you're buying new shoes, try to find those made with more eco-friendly materials.

Hemp: Hemp requires few insecticides or herbicides, doesn't require a lot of water and is a fast-growing, renewable resource.

Recycled Materials: Recycled rubber is a popular, durable material, used in the soles of shoes and in more casual footwear, like sandals and flip-flops, and more and more shoe manufacturers are using recycled plastic.

Water-based glues: Traditional shoe-making requires glues that contain volatile solvents such as toluene (read more in The Backstory). Look for water-based glues when possible.

Vegan: For those concerned about using animal products and who wish to avoid leather, look for vegan shoes, which are made without leather or other animal products (but avoid cheap vegan shoes made from the toxic plastic PVC).

Shopping Tips

• Buy used. Thrift stores and vintage clothing shops often carry a wide selection of shoes for a small fraction of the price of a new pair.

• Repair, don't replace. Most shoes simply need a new heel or reinforced sole to last another season, and cobblers are easy to find in your local yellow pages.

• Try finding shoes made in the U.S. to reduce your chances of supporting sweatshop labor. Take it a step further and buy "Union Made" (find retailers at UnionLabel.org).

• Avoid shoes labeled "Made in the Mariana Islands, USA." Although U.S. commonwealth, the Northern Mariana Islands aren't required to pay the U.S. minimum wage, and nearly 90 percent of the garment workers there were lured from developing countries by false promises of well-paid work. Many have to pay high recruiting fees then work for years to pay them back on meager earnings—a form of indentured servitude.