Soft plastic toys, or any plastic containing PVC, are the worst ones for children, since they leach the most harmful chemicals, such as lead and pthalates. However, it is best to avoid plastic toys of any kind considering their environmental impact from start (plastic is made from nonrenewable petroleum products) to finish (when they end up in landfills and oceans).

The safest playthings are made of solid wood (not pressed, which contains formaldehyde) or organic fibers. Look for organic cotton, hemp and wool, made without the pesticides and chemical fertilizers that are dangerous for kids to chew on and major water pollutants.

If you want to finish a wooden toy, use a natural oil such as nut oil or beeswax. Mineral oil, linseed oil, and any plant-based oil with a strong smell are not recommended on the toys of children under age three.