US Environmental Protection Agency (in English, Spanish and Chinese):

The site of the EPA contains constantly updated data. A "must read" for those affected by the pollution of the environment, outside (air, waterways, soil), and inside (home, workplace, etc..), and its possible effect on human health.

Also contains an educational section for children, to teach them to respect their environment, but also to warn of the dangers of domestic pesticide products, including flea collars for dogs and cats.

This Agency also reviews the dangers of chemical insecticides sold for pets once authorized and available on the market. Which leads to tighter regulations for their labeling and use, including most spot-on products.

Agricultural Research Service (USDA) (in English and Spanish):

This part of the U.S. Department of Agriculture website collects information on all living species on the planet. It contains highly technical data, especially about plants and their contents.

The Essential Oils DataBases (in English).

Those are databases which contain information on the various compositions of essential oils, based on species, and other factors, such as location.

From the Farm to the Fork:

For professionals, it is the site of the EC which includes regulatory provisions regarding foods intended for humans and animals. It should inform you, based on your activities, about the ability to use specific alternative products in your production methods. Also refer to the specifications of the various "organic" certification bodies for producers who obtained a label.

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