Diatomaceous earth is an inexpensive and effective tool to use as a dry powder on pet's fur. Apply lightly. Don't use it regularly because it's very drying to their skin.
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Regarding the different manufacturers, check the label to make sure that it does not contain Piperonyl butoxide (PBO). There are dozens of registrations of DE with the EPA for various insecticidal and food supplement uses. Piperonyl butoxide (PBO) is a synthetic synergist that is added to increase the killing power of the product. It affects the liver and should never be used. Pyrethrum products in general should be avoided.
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