These manufacturers say that the packaging of this product is biodegradable, and once mixed with other substances, they will naturally disappear or support biological growth. Researchers believe that real biodegradable substances can decompose under aerobic conditions Into carbon dioxide and water, they can decompose into methane and carbon dioxide under anaerobic conditions; however, every product tested by them can not degrade or meet the above standards. This passage mainly supports such a view:. ["This manufacturer's statement is exaggerated.", 'The manufacturer\'s "biodegradation \'" is unclear.', '"Biodegradation" can be understood differently in reality.', 'The product cannot be broken down into methane and carbon dioxide.']