TOXICOLOGY OF MICROCYSTIN-LR
Report No FR0269

J K Fawell and H A James

March 1992

SUMMARY

I OBJECTIVES

To obtain data to allow preliminary risk assessment of the hazard to man of exposure to microcystin-LR, via the oral route.

II REASONS

Blue-green algal blooms have increased in prevalence in recent years. Currently, insufficient data exist to allow an assessment of the significance to human health of the toxins (which may be produced by these algae) following algal blooms in raw water storage reservoirs.

III RESUME OF CONTENTS

A contract has been placed with Toxicol Laboratories to undertake a programme of toxicity testing with microcystin-LR, which appears to be one of the most common blue-green algal toxins.

Initial results indicate that it is more than an order of magnitude less toxic to the mouse via the oral route than via the intra-peritoneal route, and that the mouse is more sensitive than the rat.

IV CONCLUSIONS

A programme of toxicity testing has been agreed, and work has begun. The mouse will be used both for the 90 day study and the teratogenicity study. These studies will be completed in September 1992.

Copies of the Report are available from FWR, price 15 less 20% to FWR Members.