ASTM E951-94(2006)

The ED50 test provides an estimate of the amount of repellent that must be applied to the skin to produce a given level of effectiveness against the mosquito test population. The levels of effectiveness that are usually of interest are the 50 % level (for comparative purposes) and the 95 % level (for practical purposes). The ED50 test method is used to determine the effectiveness of a repellent against different kinds of mosquitoes or to compare the effectiveness of different repellents against any particular kind of mosquito. It may also be used to establish the dosages needed to provide protection under special conditions of climate, weather, activity, etc.

1.1 These test methods apply to repellent compounds and formulations that can be appropriately diluted with ethanol, acetone, or a similar inert carrier for test purposes. The test methods described are not suitable for testing powders, sticks or other solid formulations, or for testing thixotropic or other fluids whose physical properties would be modified by dilution.

1.2 These test methods are designed and intended for use as a research standard to develop data on the efficacy of repellents applied to the skin of humans against laboratory-reared or field-collected mosquitoes. The use of these test methods will provide for the development of a data base whereby all investigators generate comparable data. Modifications of the equipment or procedures, or both, may be needed for tests against other kinds of biting arthropods.

1.3 The test methods are intended for use in testing materials that are in an advanced stage of development, for which human-use trials can be fully justified on scientific and ethical grounds. The test methods are not designed for the testing of commercial formulations where registration or advertising claims data are required.

1.3.1 A repellent should not be considered for testing on humans before its efficacy has been demonstrated in in vitro, animal, or other nonhuman test systems.

1.3.2 A repellent should not be applied to the skin before its safety has been established in appropriate toxicological tests on animals or other test organisms.

1.3.3 No repellent should be tested on humans without the written consent of the test subjects and prior approval of competent authority, as designated in the applicable laws and regulations governing experimentation on humans.

1.4 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.

This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.