Recently few carrier bags are available in the market just like poly bags, but they claim these bags are biodegradable. Is there any validated method to identify whether they biodegradable or not?
An experienced customer can feel the difference between a polypropylene and a polylactide bag in the supermarket, simply touching or crumpling it by hand. A more reliable way is IR spectrophotometry for the chemical substance the bag is made of. Once the substance identified, you can look up in the literature whether it is biodegradable or not. (In the above example, polylactide is, while polypropylene is not.)