What is melamine, and can dairy products containing melamine be used to make organic fertilizer?

Melamine dealt a severe blow to dairy products, and the public dared not consume them. If tainted milk powder is used as fertilizer, will it be absorbed by crops and affect human health? Melamine is a nitrogen-containing organic compound produced from urea as a raw material; it is biodegradable, and after being decomposed into urea by microorganisms, it does not harm plants.

The Council of Agriculture, Executive Yuan, stated that farmers use dairy products as organic fertilizer when cultivating cash crops because dairy products are high in nitrogen and high in phosphorus; they are blended with various plant seed meals, such as soybean meal and peanut meal, and fermented to make organic liquid fertilizer. When farmers use milk powder as organic fertilizer, even if the milk powder contains melamine, it will not be absorbed by plants, so the public can rest assured.

Tsai Ching-chiang, deputy director-general of the Agriculture and Food Agency, stated that when farmers use milk powder as organic fertilizer, even if it contains melamine, its large molecular weight prevents it from passing through the "membrane pores" of plant root hair cells; therefore, melamine will not be absorbed by plants, and the public can consume vegetables and fruits with confidence.

The Agriculture and Food Agency explained that melamine is a nitrogen-containing heterocyclic organic compound containing 66% nitrogen; in soil, it binds with calcium, iron, and aluminum, or with components of other organic materials, to form colloidal polymers, its structure is destroyed, and its toxic effect also disappears.