4.INVENTORIES

Inventories consist of the following:

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The Company capitalizes inventory that has been produced for commercial sale and has been determined to have a probable future economic benefit. The determination of whether or not the inventory has a future economic benefit requires estimates by management. To the extent that inventory is expected to expire prior to being sold or used for research and development or used for samples, the Company will write down the value of inventory. The decrease in inventory as of June 30, 2021 of $139,773 to $828,220 from $967,993 as of September 30, 2020 is primarily attributed to an inventory obsolescence charge for shelf-life and product to be used for research and development and samples partially offset by an increase in costs to complete the manufacturing process.