LEGO bricks are made from a special plastic that can last for over 50 years without losing its shape or color.

LEGO started using Acrylonitrile Butadiene Styrene (ABS) in 1963. Before this, they used a plastic called cellulose acetate that warped over time. ABS is a thermoplastic polymer that is very tough and resists impacts.This plastic can handle a lot of pressure before it cracks. It stays solid until it reaches about 105 degrees Celsius or 221 degrees Fahrenheit. This means the bricks will not melt or soften in a hot car or under a lamp.Safety experts at labs like TÜV Rheinland test these bricks. They make sure the plastic is non-toxic and safe for children to handle. The material meets strict international toy safety rules.Researchers have studied how these bricks age over time. One study in 2017 showed that the plastic resists damage from sunlight. Bricks kept for decades still fit together perfectly because the material does not shrink or grow.