1 For a thinner stitch, less material is woven together.  Elasticity - Stitches on your knee need to be more elastic than those on your forearm, because your knee must be able to bend. Without proper elasticity, the stitches can snap and come out, or even tear the wound and delay healing.
1 Through the 1950s and 1960s, the use of exterior lead-based paint declined significantly, and ended by the early 1970s. 2  In 1971, the federal Lead Poisoning Prevention Act was passed.  In 1978, the federal government banned consumer uses of lead paint.
Since the Clean Air Act was implemented on 1 January 1996, the sale of leaded fuel has been banned for on-the-road vehicles in the United States, with possession or usage subject to high fines. Other countries have been following this example.