Note 12 - Segment and Geographic Information (Tables)

9 Months Ended

May 31, 2025

Notes Tables

Reconciliation of Revenue from Segments to Consolidated [Table Text Block]

	Three Months Ended				Nine Months Ended
	May 31, 2025		May 31, 2024		May 31, 2025		May 31, 2024
ZERUST® net sales	$	15,728,637	$	14,837,235	$	45,316,457	$	45,461,075
Natur-Tec® net sales		5,779,926		5,848,962		16,602,565		16,249,335
Total net sales	$	21,508,563	$	20,686,197	$	61,919,022	$	61,710,410

Reconciliation of Cost of Goods Sold from Segments to Consolidated [Table Text Block]

	Three Months Ended										Nine Months Ended
	May 31, 2025		% of Product Sales*			May 31, 2024		% of Product Sales*			May 31, 2025		% of Product Sales*			May 31, 2024		% of Product Sales*
Direct cost of goods sold
ZERUST®	$	9,119,330		58.0	%	$	8,168,215		55.1	%	$	25,894,213		57.1	%	$	24,994,401		55.0	%
Natur-Tec®		3,557,167		61.5	%		3,768,921		64.4	%		10,484,204		63.1	%		10,566,223		65.0	%
Indirect cost of goods sold		572,626		—			855,967		—			2,322,628		—			2,583,254		—
Total net cost of goods sold	$	13,249,123				$	12,793,103				$	38,701,045				$	38,143,878

Schedule of Segment Reporting Information, by Segment [Table Text Block]

	Three Months Ended						Nine Months Ended
	May 31, 2025			May 31, 2024			May 31, 2025			May 31, 2024
ZERUST® gross profit	$	6,609,307		$	6,669,020		$	19,422,244		$	20,466,674
Natur-Tec® gross profit		2,222,759			2,080,041			6,118,361			5,683,112
Total segment gross profit		8,832,066			8,749,061			25,540,605			26,149,786
Indirect cost of goods sold		(572,626	)		(855,967	)		(2,322,628	)		(2,583,254	)
Total gross profit	$	8,259,440		$	7,893,094		$	23,217,977		$	23,566,532
Total joint venture operations		2,272,912			2,609,228			6,377,617			7,441,476
Selling expenses		(4,375,956	)		(4,232,887	)		(12,515,638	)		(12,053,839	)
General and administrative expenses		(4,150,966	)		(3,500,113	)		(11,668,492	)		(10,253,966	)
Research and development expenses		(1,138,243	)		(1,245,405	)		(3,770,539	)		(3,593,582	)
Interest income		37,821			23,744			273,544			99,396
Interest expense		(162,096	)		(59,939	)		(421,471	)		(248,835	)
Other income		—			—			1,139,756			—
Income before income tax expense	$	742,912		$	1,487,722		$	2,632,754		$	4,957,182

Schedule of Revenue from External Customers Attributed to Foreign Countries by Geographic Area [Table Text Block]

	Three Months Ended May 31,				Nine Months Ended May 31,
	2025		2024		2025		2024
Inside the U.S. to unaffiliated customers	$	7,341,392	$	7,086,859	$	21,492,193	$	21,160,095
Outside the U.S. to:
Joint ventures in which the Company is a shareholder directly and indirectly		630,653		441,067		1,802,906		1,904,444
Unaffiliated customers		13,536,518		13,158,271		38,623,923		38,645,871
	$	21,508,563	$	20,686,197	$	61,919,022	$	61,710,410

	Three Months Ended
	May 31, 2025		% of Total Fees for Services Provided to Joint Ventures			May 31, 2024		% of Total Fees for Services Provided to Joint Ventures
Poland	$	232,064		17.8	%	$	213,102		17.6	%
Germany		218,943		16.8	%		205,853		17.0	%
Japan		158,434		12.2	%		118,606		9.8	%
Sweden		111,138		8.5	%		110,542		9.1	%
Czech Republic		110,844		8.5	%		101,111		8.3	%
Finland		95,142		7.3	%		97,437		8.0	%
United Kingdom		93,108		7.1	%		96,872		8.0	%
Thailand		87,957		6.8	%		77,206		6.4	%
South Korea		83,697		6.4	%		58,732		4.8	%
France		76,459		5.9	%		47,206		3.9	%
Other		34,812		2.7	%		85,830		7.1	%
	$	1,302,598		100.0	%	$	1,212,497		100.0	%

	Nine Months Ended
	May 31, 2025		% of Total Fees for Services Provided to Joint Ventures			May 31, 2024		% of Total Fees for Services Provided to Joint Ventures
Poland	$	637,574		17.4	%	$	628,905		16.7	%
Germany		626,999		17.1	%		618,236		16.4	%
Japan		429,520		11.7	%		366,682		9.7	%
France		312,520		8.5	%		364,348		9.7	%
Sweden		295,873		8.1	%		324,062		8.6	%
Finland		276,028		7.5	%		296,929		7.9	%
Czech Republic		251,018		6.9	%		263,712		7.0	%
Thailand		242,212		6.6	%		246,908		6.6	%
United Kingdom		237,734		6.5	%		215,123		5.7	%
South Korea		217,668		6.0	%		197,070		5.2	%
Other		129,834		3.7	%		242,539		6.5	%
	$	3,656,980		100.0	%	$	3,764,514		100.0	%

Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block]

	At May 31, 2025		At August 31, 2024
China	$	5,367,112	$	5,627,202
Other		1,238,453		1,217,400
United States		8,853,664		9,421,051
Total property and equipment, net	$	15,459,229	$	16,265,653

Revenue from External Customers by Geographic Areas [Table Text Block]

	Three Months Ended				Nine Months Ended
	May 31, 2025		May 31, 2024		May 31, 2025		May 31, 2024
China	$	4,510,490	$	3,540,570	$	12,240,359	$	10,674,939
Brazil		1,517,904		1,508,680		4,418,778		4,365,170
India		5,684,908		5,814,829		16,600,711		16,401,624
Other		2,453,869		2,735,259		7,166,981		9,108,582
United States		7,341,392		7,086,859		21,492,193		21,160,095
Total net sales	$	21,508,563	$	20,686,197	$	61,919,022	$	61,710,410