Bontan Corporation Inc. Declines an Option to Participate in a Joint Venture


TORONTO, July 21, 2004 (PRIMEZONE) -- Bontan Corporation Inc. (OTCBB:BNTNF) through its wholly owned subsidiary, Bontan Diamond Corporation ("BDC"), has decided not to exercise its previously announced option to acquire 50% working interest in a joint venture to explore and mine diamonds from the alluvium of the valley of the Paranaiba River in the Coromandel region of Minas Gerais state of Brazil. The decision was made by the Chief Geologist of BDC on the basis of newly available adverse technical data concerning the location of the joint venture.

Mr. Guardia, Chief geologist, commented, "While we are disappointed at not being able to proceed with this project as planned, we are glad that technical problems were identified at an early stage that saved our company valuable time and resources that will now be better used on other opportunities."

Mr. Kam Shah, CEO commented, "Although it is disappointing, we are encouraged by the effectiveness of our due diligence and control procedures which prevented an unprofitable financial commitment. We believe that our resident team of geologists in Brazil are now in a better position to negotiate new deals."

About Bontan Corporation Inc.:

Bontan Corporation Inc. is a diversified natural resource Company seeking high returns with minimal risks. Bontan operates, backs and invests in major exploration and exploitation plays run and organized by highly regarded geologists, geophysicists and executives.

Through its wholly owned subsidiaries, Bontan seeks highly visible opportunities in countries around the globe with a history of natural resource production that offer exciting and attractive propositions. The company will seek to minimize risk by bringing in either joint venture, carried or working interest partners, depending on the size and scale of the project.

Bontan currently has business interests in Brazil and Papua New Guinea.

For further information, please contact Kam Shah, CEO & CFO at 416-860-0175. Visit www.bontancorporation.com for more information.

For Media Relations, contact Rob Kennedy at Current Capital Corp. at 416-860-0211 or visit their website at www.currentcapital.com.

No regulatory authority has approved nor disapproved the content of this release.

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995 (the "Act"). In particular, when used in the preceding discussion, the words "plans," "confident that," "believe," "expect," or "intend to," and similar conditional expressions are intended to identify forward-looking statements within the meaning of the Act and are subject to the safe harbor created by the Act. Such statements are subject to certain risks and uncertainties and actual results could differ materially from those expressed in any of the forward-looking statements.