As biodegradable products break down in landfills, they release methane, a greenhouse gas that can harm the environment if it escapes into the atmosphere.
Only about 35% of municipal solid waste goes to landfills that capture methane for energy, according to the EPA. Another 34% of landfills capture methane and burn it on-site, but the remaining 31% allow the methane to escape.
Man-made biodegradable materials break down rapidly, a reflection of FTC guidelines calling for products labeled as biodegradable to decompose within a "reasonably short period of time." However, this quick decomposition means much of the methane in the materials will be released before a methane collection system is installed, because federal regulations allow landfills that collect methane two years to install gas collection systems.