ESV

E. S. I. Environmental Sensors Inc. ("ESI" or the "Company") (TSX VENTURE: ESV) is pleased to announce that a new SDI-12 version of the GroPoint™ Lite soil moisture sensor is now available. This new SDI-12 output will appeal to markets for existing and new irrigation systems, as well as OEM sellers. ESI is now working with key accounts to establish 2011 product needs and requirements.

ESI's GroPoint™ Lite soil moisture sensor has been available since 2009, however, the Company has previously only offered three output options: a 0 to 5 mA (milliamp), a 4 to 20 mA (high current) and a 0 to 2.5 V (voltage) output. The new SDI-12 output version of the GroPoint™ Lite soil moisture sensor will be identical in all other respects offering the same accurate, reliable and robust sensor. The small, sleek, light-weight design is extremely easy to install. This new SDI-12 version of the GroPoint™ Lite will meet the input requirements of newer irrigation controllers now being offered by several manufacturers.

SDI-12 stands for serial/digital interface at 1200 baud and is intended for applications with the following requirements: battery powered operation with minimal current drain, low system costs, use of a single data recorder with multiple sensors on one cable, and up to 200 feet of cable between a sensor and a data recorder.

This new version of GroPoint™ Lite is an analog sensor with a SDI-12 interface and output, offering a host of advantages to potential users:

--  Sensors can be interchanged without reprogramming data recorders with
    calibration or other information
--  Power is supplied to sensors through the interface
--  The use of a standard serial interface eliminates significant complexity
    in the design of data recorders
--  Data recorders can be designed and produced independently of future
    sensor development
--  Sensors can interface with any SDI-12 data recorder
--  Sensors will work with data recorders using earlier versions of SDI-12

For further information on the GroPoint™ line of soil moisture sensors, please contact the Company directly or visit our website: www.esica.com.

The next evolution in ESI's GroPoint™ soil moisture sensor development will be the development of a range of profiling sensors using both the GroPoint™ Lite and GroPoint™ Pro soil moisture sensor technologies. Using SDI-12 technology allows for multiple sensor data points on a single recorder and communication pathway, lending the two sensor technologies to relatively simple and scalable development of future profiling sensors. This presents a unique opportunity for ESI to be the only sensor company offering a highly accurate TDT-based (time domain transmissiometry) profiling sensor to the market.

In addition, the Company would like to announce the granting of 1,820,000 stock options to employees and contractors, including 1,600,000 to the Company's new President and C.E.O., Ingvard Find. Options will be priced at $0.10 per common share and will expire three years from the date of grant. Options for contractors will vest immediately, while the options for Mr. Find will vest over two years.

On September 8, 2010, the Company previously announced a grant of 1,800,000 incentive stock options priced at $0.05 per common share, which was the market price of the Company's common shares at the time of the grant. To-date, none of these incentive stock options have been exercised. TSX Venture Exchange (the "Exchange") Policy dictates that the minimum exercise price for an incentive stock option is $0.10. The Company has recently discovered this conflict and has contacted the Exchange in order to remedy the oversight. All options granted on September 8, 2010 will be retracted and re-issued at an exercise price of $0.10.

About ESI

ESI is a leading manufacturer of patented and proprietary solutions for environments where understanding the presence, movement, and/or amount of water are important. Major market sectors include: agriculture, golf and turf, scientific research, civil engineering, mining, environmental monitoring and crude oil production. ESI solutions have been successfully introduced into more than 40 countries to enable customers to optimize their operations by monitoring the presence and movement of water, managing irrigation systems, and monitoring the integrity of landfill covers. In addition, ESI's FloPoint™ instrument has been deployed in the oil industry to measure the volumetric presence of water pumped during crude oil extraction for characterization and optimization of the process. ESI differentiates itself by translating the best technology and science available into practical, easy to use solutions. Irrigation managers, reservoir engineers, and scientists have adopted ESI's products for their accuracy, ease of use, repeatability, and ability to operate in challenging environments. ESI is publicly traded on the TSX Venture Exchange under the symbol "ESV". Further information about ESI may be obtained through the Company's website at www.esica.com.

The TSX Venture Exchange has not reviewed and does not accept responsibility for the adequacy or accuracy of this release.

Contacts: E.S.I. Environmental Sensors Inc. Bernard M. Beauchesne Media and Investor Relations Contact 250.655.3211 or 1.800.799.6324 bbeauchesne@esica.com www.esica.com