SB499 is a senate bill that would mandate schools in California to replace materials that get hot easily, such as cement, asphalt, sand, rubber, and artificial turf, with materials that do not get hot easily, such as natural grass, shrubs, trees, wood chips, and cool pavement technologies, to make school environments safer. 

Heat trapping surfaces such as artificial turf and asphalt can reach dangerously high temperatures, up to 180 degrees Fahrenheit compared to grass which rarely goes above 100 degrees. In fact, UC Davis had to cancel commencement because some people passed out from heat exhaustion on the artificial turf field. 

Of the materials that must be replaced, artificial turf is a particularly important one. In addition to the dangerous "heat island" effect, artificial turf is very toxic to humans and the environment. Artificial turf is made from PFAS, per and polyfluoroalkyls or better known as forever chemicals, which do not biodegrade and have been linked to numerous negative health impacts on humans, including, but not limited to, various cancers, liver and thyroid and kidney damage, autoimmune diseases, and birth defects. Because artificial turf and other artificial materials are water impermeable surfaces, water runoff polluted by toxic forever chemicals often flows into groundwater supplies, reservoirs, and other bodies of water, poisoning people and wildlife. 

Natural systems that will replace the artificial materials have many benefits besides cooling surfaces and eliminating a major source of toxic forever chemicals. There are mental health and academic benefits as well:  Adults and students have been found to have improved attention and increased collaborative social interactions.