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亞硝酸鹽中毒表現、治療原則
方法注解

亞硝酸鹽的快速檢測
(亞硝酸鹽速測管使用說明) 方法編號:CDC-1061

1. 食鹽中亞硝酸鹽的快速檢測及食鹽與亞硝酸鹽的快速鑒別: 用袋內附帶小勺取食鹽1平勺,加入到檢測管中,加入蒸餾水或純凈水至1ml刻度處,蓋上蓋,將固體部分搖溶,10分鐘后與標準色板對比,該色板上的數值乘上10即為食鹽中亞硝酸鹽的含量mg/ kg,(國標規定食鹽(精鹽)中亞硝酸鹽的限量衛生標準應≤2 mg/kg)。當樣品出現血紅色且有沉淀產生或很快退色變成黃色時,可判定亞硝酸鹽含量相當高,或樣品本身就是亞硝酸鹽。

2. 液體樣品檢測:
直接取澄清液體樣品1ml加入到檢測管中,蓋上蓋,將試劑搖溶,10分鐘后與標準色板對比,找出與檢測管中溶液顏色相同的色階,該色階上的數值即為樣品中亞硝酸鹽(以NaNO2計)的含量mg/L。如果亞硝酸鹽的含量是以氮(N)為計算單位(如飲用水或水源水等),讀取色階上的數值后除以5即可。如果亞硝酸鹽的含量是以亞硝酸根(NO2-)為計算單位(如礦泉水、瓶裝飲用純凈水等),讀取色階上的數值后除以3.28即可。

3. 乳濁樣品檢測:
牛乳及豆槳可直接取1ml加入到檢測管中,,蓋上蓋,將試劑搖溶,10分鐘后與標準色板對比,找出與檢測管中溶液顏色相同的色階,該色階上的數值乘以2即為樣品中亞硝酸鹽的近似含量mg/L。

4. 固體或半固體樣品檢測:
取粉碎均勻的樣品1.0g或1.0ml至10ml比色管中,加蒸餾水或去離子水(純凈水)至刻度,充分震搖后放置,取上清液(或過濾或離心得到的上清液)1.0ml加入到檢測管中,蓋上蓋,將試劑搖溶,10分鐘后與標準色板對比,該色板上的數值乘上10即為樣品中亞硝酸鹽的含量mg/ kg,L(以NaNO2計)。如果測試結果超出色板上的最高值,可定量稀釋后測定,并在計算結果時乘上稀釋倍數(如從10ml比色管中取出1.0mL轉入另一支10ml比色管中,加水至刻度,從中取1.0mL加入到檢測管中測定,測試結果乘上100(稀釋倍數)即為樣品中亞硝酸鹽的含量。

部分食品、飲用水中亞硝酸鹽的限量標準參考值(以NaNO2計)

品名 限量標準mg/kg 品名 限量標準mg/kg
食鹽(精鹽)、牛乳粉 ≤2 香腸(臘腸)香肚、醬腌菜、廣式臘肉、火腿 ≤20
鮮肉類、鮮魚類、糧食 ≤3 肉制品、火腿腸、灌腸類 ≤30
蔬菜 ≤4其 他肉類罐頭、其他腌制罐頭 ≤50
嬰兒配方乳粉、鮮蛋類 ≤5 西式蒸煮、煙熏火腿及罐頭、西式火腿罐頭 ≤70
以N-計:生活飲用水≤1mg/L
以NO2-計:礦泉水≤0.005 mg/L,瓶裝飲用純凈水≤0.002 mg/L

5 注意事項
5.1 亞硝酸鹽含量較高時,試劑顯紅色后不久會變為黃色,將黃色溶液再稀釋放 入另一新的速測管中又會顯出紅色,由此區分是亞硝酸鹽還是食用鹽。
5.2 當樣品反應后的顏色大于標準色板2.00mg/L色階時,應將樣品稀釋后再測, 計算結果時乘上稀釋倍數。
5.3 生活飲用水中常有亞硝酸鹽存在,不宜作為測定用稀釋液。

6 試劑質量控制
6.1 將0.025、0.1、0.25、0.5、1、2、5mg/LNaNO2標準溶液分別加入裝有固體格 林試劑的速測管,蓋蓋將試劑搖溶,10min后與標準色板進行對比,其含量與 色板上的色階標識含量應當相同或相近。
6.2 試劑常溫避光保存,有效期18個月。

7 參數
7.1 檢出限:0.05mg/L
7.2 線性范圍:0.05~5.0 mg/L

  
圖像1.水中的亞硝酸鹽    圖像2.牛乳中的亞硝酸鹽

Introduction for Nitrite Test Tubes
1. The rapid detection of nitrite salt: Take 1 spoon of sample to the test tube, add distilled water or purified water to 1ml scale office, sealed cover and shake the solid part of the dissolution, after 10 minutes with standard color contrast, the value of the color board shall be multiplied by 10, the salt content of nitrite in mg / kg, (national standard salt (salt) nitrite the limited health standards should be ≤ 2 mg / kg). When the sample appears red and there is precipitation in the blood or quickly fade into a yellow, it can determine a high nitrite content, or the sample itself is nitrite.

2. Liquid sample testing: Take clarify liquid sample 1ml to test tube, covered with lid, shake to dissolve reagents, standard color after 10 minutes, compared with the test tube to find the solution in the same color gamut, the Levels on the sample values shall nitrite (in NaNO2 dollars) content mg / L. If the content is based on nitrite nitrogen (N) as the unit (such as drinking water or water in the water, etc.), after reading the value on the color scale, the final number should be divided by 5. If the content of nitrite based on nitrite (NO2-) as the unit (such as mineral water, bottled drinking water, etc.), after reading the value on the color scale can be divided by 3.28.

3. Opaque sample test: milk and beans to take 1ml paddle directly to test tube, covered with lid, shake to dissolve reagents, standard color after 10 minutes, compared with the test tube to find the solution of the same color Levels of the color scale on the value shall be multiplied by 2, the approximate sample concentration of nitrite mg / L.

4. Solid or semi-solid sample test: take a uniform sample crushed 1.0g or 1.0ml to 10ml colorimetric tube, add distilled water or deionized water (pure water) to the mark placed after shaking, and the supernatant ( or filtration or centrifugation supernatant) 1.0ml added to the test tube, covered with lid, shake to dissolve reagents, 10 minutes compared with the standard color, the color board shall be the value multiplied by 10 samples in Central Asia Nitrate content mg / kg, L (to NaNO2 dollars). If the test results over the maximum value of outstanding board can be measured by dilution and multiplied in the calculation results of the dilution factor (eg, from 10ml remove 1.0mL cuvette into Another 10ml colorimetric tube, add water to scale in order to reap 1.0mL test tube to the determination of test results multiplied by 100 (dilution) is the nitrite content of the sample.

Description:
① there are small amounts of drinking water often can not be the determination of nitrite diluent.
② If the color of deep color and a precipitate produced or soon fade into pale yellow, indicating a high nitrite content of samples required to increase the dilution re-determination.
③ excessive sample should be repeated on the experiment, when sent to the laboratory conditions to accurate quantification.
④From light at room temperature for 18 months period, production date, see packaging.

京ICP備05027438號     2000年創刊-北京中衛食品衛生科技公司
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