Melamine is a triamine compound that was first discovered and synthesized in the early 1800s. It is deaminated to the oxytriazine structural analogues Ammeline, Ammelide, and cyanuric acid. Melamine is a chemical compound used in a variety of materials used in cleaning products, dry wipe boards and plastics, among other applications. Melamine is synthesized from urea, requires several purification steps, and is marketed in various purities, the lowest of which is contaminated with oxytriazine. Problems with melamine and oxytriazine contamination in food have been linked to rapid and unregulated production.

Between 2003 and 2008, several major pet food and human food safety incidents involving melamine occurred worldwide, leading to significant increases in morbidity and mortality among children, cats, dogs, poultry and pigs. Melamine and other nitrogen-rich oxytriazine compounds are added to feed ingredients to falsely boost apparent protein levels, and are used not only in pet food but also in livestock and fish feed. Major pet food companies have recalled more than 1,000 types of commercial pet food worldwide. During an outbreak of kidney failure in dogs and cats in the United States in 2007, veterinary diagnostic laboratories found melamine and triazine in many suspect foods. Later tests showed the presence of melamine in vegetable powder, milk powder, adhesives and goods. Melamine and cyanuric acid have been shown to cause acute renal failure in cats and dogs in many previous cases.

Melamine poisoning, such as the recent incident in animals, is characterized by acute renal failure, uremia, anorexia, anuria, polydipsia, lethargy and occasional vomiting, accompanied by azotemia and hyperphosphatemia.

Melamine produces similar effects in mammals with certain species-specific mutations. In dogs, the kidneys are green and there are green uroliths in the renal pelvis or bladder. Histologically, crystals are present in the intraluminal space of the renal tubules and in the urine and renal touchmarks. Melamine-associated crystals are brown or green and have a rough surface, but the crystals are round and have a common radial layered orientation called windmill radiation fringe. The fan-shaped crystals exhibit bright birefringence when viewed under cross-polarized light.

There is no known antidote to melamine poisoning. Treatment includes discontinuation of problematic feed, liquid diuresis, alkalized urine and other supportive therapies. MPP has a significant barrier effect in the condensed phase by diluting the vapor phase with fuel. Its combination with AlPi results in carbonization and better barrier effect. These effects are ameliorated by the presence of ZnB due to the formation of aluminum borophosphate rather than aluminum phosphate, say the authors.