Everyone is affected directly or indirectly by pesticide use and safety. The magnitude and perception of this effect depend on one's individual involvement or vantage point. The researcher seeks discovery and the entrepreneur goes after financial rewards. The general public wants food, health and safety. Pesticide toxicology is a core issue in these relationships. The three goals of toxicology research on pesticides are first to create new knowledge and chemicals, second to evaluate their effectiveness and safety and third to regulate their use. What amounts of pesticides are applied and do we really understand their biology and chemistry? This review addresses the ABCs of pesticide toxicology, i.e. their amounts, biology and chemistry.