ABEL-TOX ™ On-line Toxicity Monitoring System
ABEL-TOX™ is an on-line toxicity monitor for real-time continuous monitoring of industrial effluent at the site of discharge as well as from a water course into which effluent is discharged.
ABEL-TOX™ patented on-line toxicity monitoring system is based on the continuous culture of bioluminescent micro-organisms which are continuously mixed, in one line with a reference liquid and in another with a stream of liquid of unknown toxic content. In the presence of toxic materials, the light emitted by the micro-organisms is decreased in proportion to the amount of toxic material present. A third line containing liquid passes through a delay coil and back into the stream unless toxicity is detected; in such an event a valve switches the stream for collection in security sealed and time coded containers.
Bioluminescent micro-organisms are grown in a continuous culture system and are continuously mixed with a reference stream of known toxicity and one or more streams of liquid (in different lines) of unknown toxicity. The micro-organisms can be naturally occurring marine bacteria, for example, or bioluminescent micro-organisms produced by genetic engineering; cells transfected with luminescent genes can also be used in the system.
Light emitted from the micro-organisms is detected in an online dual monitoring luminometer as it passes through twin flow cells. Any significant difference in the amount of light detected from the reference and monitoring streams will lead to a number of programmable events: an alarm can be programmed, a valve can switch to collect samples for further analysis from a third line containing samples in a delay coil which would normally be passed back into the sampling stream. The samples collected for further analysis (or for prosecution purposes) are security sealed and time coded.
More than one sampling line can be run from one continuous culture or more than one culture (with bioluminescent micro-organisms with different properties) can be used to screen for toxicity. Matching the appropriate micro-organism for the type of liquid stream to be monitored with regard to sensitivity for a particular analyte or for the type of effluent being monitored is essential as a micro-organism which was very sensitive would be suitable for assessing drinking water while being unsuitable for industrial effluent, where much higher toxic loads are permitted.
As the system produces excess micro-organisms samples of bioluminescent micro-organisms can be obtained from a on-way tap enabling additional toxicity testing, at no extra cost per test, to be performed with a portable luminometer designed for manual sampling; such an instrument will be available as an optional extra and will be especially useful to identify places where further lines might be added for continuous monitoring.
Other parameters: pH, temperature, osmolality, colour can also be measured on line. The whole system can built with replaceable disposable components to reduce the need for skilled maintenance.
The continuous culture of bioluminescent micro-organisms producing steady light output and used for monitoring toxicity is the main innovation of this system. The ability to monitor continuously and in real-time is another innovation allowing for 24 hour continuous monitoring at very low cost. The ability to cultivate native and/or recombinant micro-organisms with specific characteristics to allow monitoring of a wide range of analytes and at different concentrations is also innovative. In this way a particular system can be set up in a manufacturing plant, for example, to screen for particular analytes or micro-organisms can be grown which are suitable for assessing toxicity of drinking-water quality (very sensitive) or other less sensitive micro-organisms used to assess the toxic effect of industrial effluent on the micro-organisms in the sewage system when the effluent is discharged into a water course.
