One kilogram of a pesticide is not necessarily equal to a kilogram of a different pesticide. This issue can be significant. Whether it is depends on the use to which pesticide-use data are put. While kilograms of pesticide is the most common way of measuring agricultural chemical use, the type of analysis will generally define what measure of chemical use is best. Quantifying the risk from the exposure to pesticides, for example, typically requires weighing usage or residues by acute or chronic health and environmental toxicity coefficients and subsequently estimating human or environmental exposure to such hazards. The interferences one draws concerning pesticide use can vary substantially depending on the measure considered.