Extraction methods, effects potency

Many plant metabolites marketed as natural pesticides are in fact more toxic than their synthesized competitors for example, rotenone (extracted from the roots of certain members of the bean plant family) has been used as a crop insecticide since the mid-19th century to control leafeating caterpillars, but is six times more toxic to mammals on a strictly comparable basis than carbaryl, a synthetic chemical also effective for caterpillar control. Nicotine sulfate is extracted from tobacco by steam distillation or solvent extraction and has been used as a pesticide since the early 20th century it is six times more toxic than diazinon, a widely available synthetic insecticide sold for control of many of the same pests. The best known work in this area (Ames 1990, 1990a, 1997) used the Ames test (Ames 1973, 1973a) to compare potencies of natural and synthetic pesticide compounds with respect to mutagenicity in special bacterial strains. While some of the conclusions of this work are controversial (Tomatis 2001), it does at least emphasize the importance of development of analytical methods for natural as well as synthetic compounds in foodstuffs. In this section an example of each is considered. 

---