OAKVILLE, Ontario, October 8, 2003 - ZENON Environmental Inc.  announced that the company today filed a patent infringement lawsuit against US Filter Corporation.   ZENON is seeking damages and an injunction to stop the sale, manufacture and use of US Filter's MemJet and CFM-S products that infringe ZENON's intellectual property, protected by patents issued in the United States.

The lawsuit, filed in the United States District Court for the Southern District of California, alleges that US Filter's MemJet and CMF-S immersed membrane products infringe ZENON's United States Patent Nos. 6,245,239 and 6,550,747 relating to the use of air cycling to keep membranes clean and its United States Patent No. 6,620 319 relating to membrane module configuration.

"The growing need for better, faster and cheaper water filtration and wastewater management solutions requires a steady stream of innovation," said Andrew Benedek, Chairman and CEO of ZENON.  "While we welcome innovators to the market, ZENON has an obligation to protect the investment made in our technology by shareholders, partners and customers."

"Protecting innovation is something companies across industries do in order to ensure continued innovation," said Lisa Bolton, ZENON General Counsel.  "Our industry is no different.  We do not take this step lightly.  But, we are confident in our decision to proceed with this lawsuit and will take action as necessary to protect our intellectual property."

Dr. Benedek added, "ZENON is dedicating our company to business as usual throughout the litigation process.  We are successful because of our focus on developing, selling and supporting advanced immersed membrane technologies in the market.   Customers will see no change in that regard."

ZENON manufactures advanced membrane products and services for water purification, wastewater treatment and water reuse to municipalities and industries worldwide.