THE DEVELOPMENT OF IMMUNOASSAY KITS FOR THE ANALYSIS OF PESTICIDES AND OTHER ORGANICS IN WATER
Report No FR0444

P GALE, B HEGARTY, K WILSON AND C D WATTS

APRIL 1994

SUMMARY

I BENEFITS

An up-to-date review is provided of commercially available kits and new developments for enzyme immunoassay of organics in potable and raw waters enabling Water Industry staff to make informed judgements on the utility of these simple, inexpensive procedures for their monitoring requirements.

II OBJECTIVES

To review the availability of enzyme immunoassay kits for analysis of pesticides and other substances of concern to the water industry. To evaluate the kits in relation to water industry requirements and conventional analytical methods. To stimulate the development of appropriate kits by discussion of the water industry' s requirements with the leading enzyme immunoassay kit manufacturers. To report on the kits developed for the analysis of atrazine and uron pesticides.

III REASONS

Conventional methods for the analysis of pesticides and other organic chemicals in water often use techniques such as high-performance liquid chromatography and gas chromatography. This requires the use of relatively expensive instrumentation and genera lly does not produce rapid results. Methods based on immunoassay have the potential to provide an inexpensive and rapid analytical technique for water quality monitoring and to provide support to existing monitoring. For substances that are relatively difficult to measure and require frequent monitoring by the water industry, immunoassay methods can provide a cheap, quick and simple approach. Atrazine and isoproturon are herbicides that would benefit from such methodology.

IV CONCLUSIONS

The two main manufacturers of immunoassay kits, J T Baker (Ohmicron) and Millipore (Immunosystems) have been made aware of the performance required for their kits to comply with the Drinking Water Directive guidelines. Both manufacturers have kits for a trazine which with improvements underway should achieve this performance and a small UK manufacturer, Guildhay, has developed kits for atrazine and isoproturon with funding from FWR which achieve this performance. Many other kits are available for organic chemicals which offer inadequate performance for drinking water, but if the atrazine and isoproturon kits are commercially successful then further high performance enzyme immunoassays will be developed by the manufacturers.

V RECOMMENDATIONS

The discussions with manufacturers on water industry requirements should be continued and they should be encouraged to submit their data to the DoE's Standing Committee of Analysts (Panel 6.3 - Pesticides) for production of a `Blue Book' for atrazine and isoproturon based on enzyme immunoassay methods. The high performance kits for atrazine and isoproturon, which achieve results comparable with conventional analytical techniques, are recommended for use in laboratories as a rapid and inexpensive screening method in support of slower and more sophisticated conventional techniques such as GC and HPLC.

VI RESUME OF CONTENTS

The performance required of enzyme immunoassay kits to meet the Drinking Water Inspectorate's (DWI) guidelines for analysis of pesticides in water is discussed and a draft `Blue Book' style specification and comments on this from DWI are presented.

The report reviews commercially available and new developments in enzyme immunoassay kits for analysis of pesticides and other organic chemicals in water in the light of DWI requirements. Information is given on the development and performance of kits for atrazine and isoproturon funded by this contract.

Copies of the Report are available from FWR, price 25.00 less 20% to FWR Members