Zinc pest

[1] While impurities of the alloy are the primary cause of the problem, environmental conditions such as high humidity (greater than 65%) may accelerate the process.

[2] Affected objects may show surface irregularities such as small cracks and fractures, blisters or pitting.

Zinc pest is dreaded by collectors of vintage die-cast model trains, toys, or radios, because rare or otherwise valuable items can inescapably be rendered worthless as the process of zinc pest destroys them.

Since the 1940s, some model railroad hobbyists have claimed,[citation needed] with varying degrees of success, that a method of "pickling" zinc alloy parts by soaking them in vinegar or oxalic acid solution for several minutes before painting and assembling them could prevent or delay the effects of zinc pest.

Engine parts of older vehicles or airplanes, and military medals made of zinc alloys, may also be affected.