What is indicated by part per million?

Part per million (ppm) is a unit of measurement that expresses the concentration of a substance in a solution or mixture. Specifically, it indicates one part of a substance for every one million parts of the total solution or mixture. This means if you have a solution that contains a contaminant or chemical at a concentration of 10 ppm, there would be 10 grams of that substance in one million grams of the solution. This metric is particularly useful in environmental science, chemistry, and aquatics for assessing levels of pollutants or chemicals in water. Understanding ppm is essential in aquatic pest management to make informed decisions regarding the use of chemicals and treatments without negatively impacting the ecosystem.