filtration
I'm not certain about plastic or metal toys, but I found this great article about safe paints for wooden toys that might be helpful. http://woodentoys.xanga.com/733196515/wooden-toy-finishes---paints-and-sealents/
you mean from wooden to plastic? it's cheaper to make in plastic
Plastic patio benches are more weather resistant than wooden ones. Wooden can rot. Plastic won't deteriorate in any weather.
wooden
Many of the wooden pallets are treated with industrial pesticides. This is a concern for many. This is one reason why plastic pallets are beneficial as compared with wooden ones; they aren't treated with insecticides. Also Wooden pallets are often constructed out of wood that has lots of spliters. Caution must be used when handling them. This is another benefit of plastic pallets over wooden pallets-no spliters. A plastic pallet is water proof compared to a wooden one. In adddition, a plastic pallet generally lasts about 2 to 3 years longer than wooden pallet.
wood
The oboe is made of ebony. Most oboes are wooden, but some are black plastic. Wooden oboes cost up to double the amount of plastic ones.
One major benefit over plastic shades is the wooden ones are far less likely to warp or fade with the heat of the sunshine on them. Wooden shades also keep out more light because they are not translucent like plastic shades.
Plastic
wooden by far is the best...you get such a better beat with them.
Wooden sandboxes usually look nicer and are sturdier and more ecologically friendly, but plastic sandboxes are typically cheaper, are fun, and are more low maintenance that wooden ones.
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