"Nicotine Sulfate
Nicotine is extracted from tobacco or related Nicotiana species and is one of the oldest botanical insecticides in use today. It's also one of the most toxic to warm-blooded animals and it's readily absorbed through the skin. (Wear gloves when applying it, follow label directions and keep pets away from application areas.) It breaks down quickly, however, so it is legally acceptable to use on organically grown crops.
Nicotine sulfate is sold as a 40 percent nicotine sulfate concentrate under trade names that include Black Leaf 40 or Tender Leaf Plant Insect spray. Nicotine kills insects by interfering with the transmitter substance between nerves and muscles. It's commonly used to control aphids, thrips, spider mites and other sucking insecticides on most vegetables, some fruits, flowering plants and ornamental shrubs and trees. Roses are sensitive to nicotine. Choose alternate pest control measures when treating insects on roses.
Nicotine sulfate has a DANGER warning."