Quality assurance of imposex and intersex measurements in marine snails

Collaboration between the QUASIMEME and BEQUALM projects has proved to be an effective mechanism to further the development of quality assurance procedures for the measurement of the biological effects of tributyltin (imposex and intersex) to meet the requirements of international and national marine monitoring programmes. The data arising from the Laboratory Performance Studies are demonstrating the level of agreement between laboratories, suggesting factors leading to differences between laboratories, and guiding the development of QA procedures.