chemistry Chemistry is the scientific study of the properties and behavior of matter. It is a natural science that covers the elements that make up matter to the compounds made of atoms, molecules and ions: their composition, structure, proper ...

, chemical purity is the measurement of the amount of

impurities In chemistry and materials science, impurities are chemical substances inside a confined amount of liquid, gas, or solid, which differ from the chemical composition of the material or compound. Firstly, a pure chemical should appear thermodynami ...

found in a

sample Sample or samples may refer to: Base meaning * Sample (statistics), a subset of a population – complete data set * Sample (signal), a digital discrete sample of a continuous analog signal * Sample (material), a specimen or small quantity of ...

. Several grades of purity are used by the scientific, pharmaceutical, and industrial communities. Some of the commonly used grades of purity include: * ACS grade is the highest level of purity, and meets the standards set by the

American Chemical Society The American Chemical Society (ACS) is a scientific society based in the United States that supports scientific inquiry in the field of chemistry. Founded in 1876 at New York University, the ACS currently has more than 155,000 members at all ...

(ACS). The official descriptions of the ACS levels of purity is documented in the '' Reagent Chemicals'' publication, issued by the ACS. It is suitable for food and laboratory uses. * Reagent grade is almost as stringent as the ACS grade. * USP grade meets the purity levels set by the

United States Pharmacopeia The ''United States Pharmacopeia'' (''USP'') is a pharmacopeia (compendium of drug information) for the United States published annually by the United States Pharmacopeial Convention (usually also called the USP), a nonprofit organization that ...

(USP). USP grade is equivalent to the ACS grade for many drugs. * NF grade is a purity grade set by the

National Formulary A formulary is a list of pharmaceutical drugs, often decided upon by a group of people, for various reasons such as insurance coverage or use at a medical facility. Traditionally, a formulary contained a collection of formulas for the compounding ...

(NF). NF grade is equivalent to the ACS grade for many drugs. * British Pharmacopoeia: Meets or exceeds requirements set by the

British Pharmacopoeia The ''British Pharmacopoeia'' (''BP'') is the national pharmacopoeia of the United Kingdom. It is an annually published collection of quality standards for medicinal substances in the UK, which is used by individuals and organisations involv ...

(BP). Can be used for food, drug, and medical purposes, and also for most laboratory purposes. *Japanese Pharmacopeia: Meets or exceeds requirements set by the

Japanese Pharmacopoeia The is the official pharmacopoeia of Japan. It is published by the . The first edition was published on 25 June 1886, with revisions being issued from time to time. The current revision is number 18, issued electronically on 7 June 2021. An offi ...

(JP). Can be used for food, drug, and medical purposes, and also for most laboratory purposes. * Laboratory grade is suitable for use in educational settings, but is not acceptable for food or drug use. * Purified grade is not precisely defined, and it is not suitable for drug or food usage. * Technical grade is suitable for industrial applications, but is not acceptable for food or drug use.

References

{{reflist Materials Chemical tests Environmental chemistry Adulteration Harm reduction