The use of synthetic pesticides continues to be permitted for farmers and professionals registered to work in the gardening business.
Synthetic pesticides are “a substance that is formulated or manufactured by a chemical process or by a process that chemically changes a substance extracted from naturally occurring plant, animal, or mineral sources.” Synthetic pesticides are often referred to as conventional pesticides.
Of course natural products can be equally as harmful if used excessively or in concentrated form. For example salt, vinegar, detergents and even Jeyes fluid are often promoted as being natural but all can and will cause serious environmental harm.
Natural products that have been approved can be found on this PDF list.