Melamine cyanurate, also known as melamine–cyanuric acid adduct or melamine–cyanuric acid complex, is a

crystal A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macros ...

line

complex Complex commonly refers to: * Complexity, the behaviour of a system whose components interact in multiple ways so possible interactions are difficult to describe ** Complex system, a system composed of many components which may interact with each ...

formed from a 1:1 mixture of

melamine Melamine is an organic compound with the formula C3H6N6. This white solid is a trimer of cyanamide, with a 1,3,5-triazine skeleton. Like cyanamide, it contains 67% nitrogen by mass, and its derivatives have fire retardant properties due t ...

and

cyanuric acid Cyanuric acid or 1,3,5-triazine-2,4,6-triol is a chemical compound with the formula (CNOH)3. Like many industrially useful chemicals, this triazine has many synonyms. This white, odorless solid finds use as a precursor or a component of bleaches ...

. The substance is not a

salt Salt is a mineral composed primarily of sodium chloride (NaCl), a chemical compound belonging to the larger class of salts; salt in the form of a natural crystalline mineral is known as rock salt or halite. Salt is present in vast quantitie ...

despite its non-systematic name ''melamine cyanurate''. The complex is held together by an extensive two-dimensional network of

hydrogen bond In chemistry, a hydrogen bond (or H-bond) is a primarily electrostatic force of attraction between a hydrogen (H) atom which is covalently bound to a more electronegative "donor" atom or group (Dn), and another electronegative atom bearing a ...

s between the two compounds, reminiscent of the

guanine Guanine () ( symbol G or Gua) is one of the four main nucleobases found in the nucleic acids DNA and RNA, the others being adenine, cytosine, and thymine (uracil in RNA). In DNA, guanine is paired with cytosine. The guanine nucleoside is called ...

–

cytosine Cytosine () ( symbol C or Cyt) is one of the four nucleobases found in DNA and RNA, along with adenine, guanine, and thymine (uracil in RNA). It is a pyrimidine derivative, with a heterocyclic aromatic ring and two substituents attached (an am ...

base pair A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA ...

s found in DNA. Melamine cyanurate forms spoke-like

s from aqueous solutions and has been implicated as a causative agent for toxicity seen in the

Chinese protein export contamination In China, the adulteration and contamination of several food and feed ingredients with inexpensive melamine and other compounds, such as cyanuric acid, ammeline and ammelide, are common practice. These adulterants can be used to inflate the ap ...

and the 2007 pet food recall.

Chemistry

The substance is best described as a melamine-cyanuric acid

, or non-covalent

adduct An adduct (from the Latin ''adductus'', "drawn toward" alternatively, a contraction of "addition product") is a product of a direct addition of two or more distinct molecules, resulting in a single reaction product containing all atoms of all co ...

. The two compounds do not form a

as suggested by its colloquial name ''melamine cyanurate''.

Uses

Melamine cyanurate is used as a

flame retardant The term flame retardants subsumes a diverse group of chemicals that are added to manufactured materials, such as plastics and textiles, and surface finishes and coatings. Flame retardants are activated by the presence of an ignition source a ...

, most commonly in

polybutylene terephthalate Polybutylene terephthalate (PBT) is a thermoplastic engineering polymer that is used as an insulator in the electrical and electronics industries. It is a thermoplastic (semi-)crystalline polymer, and a type of polyester. PBT resists solvents, s ...

(PBT),

polyamide 6 Nylon 6 or polycaprolactam is a polymer, in particular semicrystalline polyamide. Unlike most other nylons, nylon 6 is not a condensation polymer, but instead is formed by ring-opening polymerization; this makes it a special case in the comparis ...

(nylon 6) and

polyamide 6,6 Nylon 66 (loosely written nylon 6-6, nylon 6/6, nylon 6,6, or nylon 6:6) is a type of polyamide or nylon. It, and nylon 6, are the two most common for textile and plastic industries. Nylon 66 is made of two monomers each containing 6 carbon atoms, ...

(nylon 6:6).

Toxicity

It has been considered to be more toxic than either melamine or cyanuric acid alone. in rats and mice (ingested): * 4.1 g/kg – Melamine cyanurate * 6.0 g/kg – Melamine * 7.7 g/kg – Cyanuric acid A toxicology study conducted after recent pet food recalls concluded that the combination of melamine and cyanuric acid in diet does lead to

acute kidney injury Acute kidney injury (AKI), previously called acute renal failure (ARF), is a sudden decrease in kidney function that develops within 7 days, as shown by an increase in serum creatinine or a decrease in urine output, or both. Causes of AKI are cla ...

in cats.Puschner et al. (November 2007). Assessment of melamine and cyanuric acid toxicity in cats. Journal of Veterinary Diagnostic Investigation. Retrieved on 2007-11-16. A 2008 study produced similar experimental results in rats and characterized the melamine and cyanuric acid in contaminated pet food from the 2007 outbreak.

References

{{Reflist Amines Triazines Nephrotoxins Triketones Flame retardants

Chemistry

Uses

Toxicity

See also

References