Pistachio nuts can spontaneously combust when shipped in large batches. The nut's high oil content and low water content mean that large batches can self-heat to the point where they catch on fire. Pistachios also absorb oxygen and put out carbon dioxide, so they can be a health hazard when they are in large amounts in enclosed areas, such as in cargo ships or delivery trucks. This is why pistachio nuts have to be shipped under very careful conditions and must be regularly monitored for temperature during the shipping process.

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