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水里亚硝酸盐多少正常
更新时间: 2020-11-02 00:00:00  

我国桶装水的卫生标准规定,水中亚硝酸盐的含量不得超过2微克/每升。通常水里的亚硝酸盐不会凭空产生,一般是由水中原有的硝酸盐转化而来。合格的饮用水中,硝酸盐很少;但如果水源被含氮有机物污染,硝酸盐含量就可能增加。通常来说,饮水反复加热导致亚硝酸盐增加的原因,主要是水蒸发浓缩,亚硝酸盐浓度增加,但总量并不增加;另一种可能是,某些硝酸盐受热分解成亚硝酸盐。

关键词: 亚硝酸盐 多少 正常

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