The contamination in the central air conditioning duct system is the one of the principal contamination of the indoor air, it include inhalable particle and microorganism.

中央空调通风系统送风中的污染物是室内空气的主要污染源之一，主要的污染物是可吸入颗粒物和微生物。

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Under the intrude of the wastewater and particle power and mine gangue, the soil was suffered different level contamination, which did harm to agro-ecosystem and man health.

矿区土壤在矿山废水、粉尘以及矿山尾矿等的侵入下受到了不同程度的污染，给矿区的农业生态系统和人们的健康带来了危害。

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