Prop 65 does not limit the types or amounts of chemicals that can be put into products, as long as the warning is given. It does set a “safe harbor” exposure level for about a third of the listed chemicals, below which no warning is required. However, the cost and complexity of performing an exposure analysis to determine whether the concentration of the listed chemical is below the “safe” level is significant. As a result, many companies find it more cost-effective to simply label their products if they believe any level of a listed chemical may be present. So even the impact of labeling could be seen as marginal.