The presence of bacterial endotoxins in different media, solutions and laboratory materials can be determined by utilising the limulus amebocyte lysate test. Lisa Komski at Fujifilm explains that, for routine testing in the quality control laboratory, it remains of vital importance to establish a reliable and reproducible method of testing so that any reaction can be examined to determine if the cause is indeed due to endotoxin or to the presence of (1,3)-?-D-glucan.