GBZ/T 317.1-2018Determination of cadmium in blood -- Part 1: Graphite furnace atomic absorption spectrometry method (English PDF)

Foreword

This standard is formulated in accordance with the Law of the People's Republic GBZ/T 317 "Determination of Cadmium in Blood" is divided into two parts.

-- Part 1. Graphite furnace atomic absorption spectrometry.

-- Part 2. Inductively coupled plasma mass spectrometry.

This part is the first part of GBZ/T 317.

This part is drafted in accordance with the rules given in GB/T 1.1-2009.

This section replaces WS/T 34-1996 "Method for the determination of cadmium in blood by graphite furnace atomic absorption spectrometry".

The main changes compared to WS/T 34-1996 are as follows.

-- Improved standard formulation and sample handling methods.

This section is mainly drafted by. China Center for Disease Control and Prevention, Occupational Health and Poison Control Institute, Guangdong Provincial Occupational Disease Prevention and Treatment Institute, Jiangsu Provincial Center for Disease Control and Prevention, Shandong Institute of Occupational Health and Occupational Diseases.

1 Scope

This part of GBZ/T 317 specifies graphite furnace atomic absorption spectrometry for the determination of cadmium in blood.

This section applies to the determination of cadmium and its compounds in the blood of occupational contacts.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only the dated version applies to this document.

For undated references, the latest edition (including all amendments) applies to this document.

GBZ/T 295 General rules for occupational health biological monitoring

3 Principle

Blood samples (hereinafter referred to as blood samples) were extracted with a nitric acid solution and determined by graphite furnace atomic absorption spectrometry at a wavelength of 228.8 nm.

The concentration of cadmium.

4 Instruments

4.1 Blood collection supplies. disposable blood collection needle, sterile cotton swab, lithium heparin (sodium) vacuum blood collection tube, etc.

4.2 Volumetric flask. 5mL.

4.3 stoppered polyethylene centrifuge tube. 1.5mL.

4.4 Vortex mixer.

4.5 Centrifuge. The speed is greater than 10000r/min.

4.6 Micropipette. The range is 20µL~200µL and 100µL~1000µL.

4.7 Atomic Absorption Spectrometer. with graphite furnace, cadmium hollow cathode lamp and background correction device. Refer to Table 1 for instrument operation reference conditions.

Table 1 Instrument operation reference conditions

step

temperature

Heating time

Residence time

Carrier gas flow

mL/min

Drying 110 5 10 250

Drying 130 10 20 250 Ashing 500 20 30 250 Atomic 1800 0 3 0 Clear 2300 1 5 250 Note. The above conditions are provided for the convenience of standard users. If the conditions are changed, the same effect should be achieved.

5 Reagent

5.1 Deionized water, medical alcohol.

5.2 Nitric acid, excellent grade pure, rho20=1.42g/mL.

5.3 Nitric acid solution, 0.2% (volume fraction).

5.4 Nitric acid solution, 1% (volume fraction).

5.5 Nitric acid solution, 5% (volume fraction).

5.6 Heparin anticoagulated bovine blood, stored at -20 ° C, shake to room temperature when used. Heparin anticoagulated sheep blood can also be used. Background cadmium content should be Less than 0.2 µg/L.

5.7 Standard solution. Nationally approved cadmium monolith standard solution.

6 Sample collection, transportation and storage

6.1 Environmental conditions. The blood collection site should be clean and tidy, and there is no source of cadmium pollution.

6.2 Personnel requirements. After rigorous training and familiarity with the blood collection process, wear powder-free latex gloves.

6.3 Sample collection. Sample collection is performed according to GBZ/T 295. Clean blood with 0.2% nitric acid solution, deionized water and medical alcohol for the skin of the site, the blood sample should be collected more than 2 mL, and shake immediately to prevent clot formation in the blood. Collect duplicate samples if necessary, One copy as a backup sample.

6.4 Sample blank. randomly take 2 parts of the blood collection container with the same batch number as the sample collection, and use the same batch of blood collection needle to extract 2.0 mL of deionized water.

In the blood collection tube, it is used as a sample blank.

6.5 Sample transportation. Store the collected samples and sample blanks in a clean container for refrigerated transport.

6.6 Sample storage. The sample can be stored for half a year at -20 °C.

7 Analysis steps

8 Calculation

Calculate the concentration of cadmium in the blood sample according to formula (1).

C = C0 (1)

In the formula.

C - concentration of cadmium in blood in micrograms per liter (µg/L);

C0 - Concentration of cadmium in blood samples obtained from the working curve or regression equation in micrograms per liter (µg/L).

9 Description

9.1 The detection limit of this method is 0.24 µg/L, the lower limit of quantification is 0.70 µg/L; the measurement range is 0.70 µg/L to 12.0 µg/L. relatively the standard deviation ranges from 2.1% to 5.2% (n=6).

9.2 The injection volume of this method can be determined according to the specific conditions of the instrument, generally choose 10 µL ~ 20 µL.

9.3 In this method, the matrix has an influence on the measurement. The sample should be treated in the same way as the working curve series solution. If the cadmium concentration in the sample is super After the measurement range, the blood cadmium working curve range can be increased to 24.0 µg/L, and the standard series and samples are treated by the 10-fold dilution method.

The measurement was carried out by taking 0.10 mL of blood and adding 0.90 mL of a 5% nitric acid solution.

9.4 Disposable articles such as vacuum blood collection tubes, stoppered polyethylene centrifuge tubes and micro-pump tips should also be tested by background sampling.

For use, the sampling amount of each batch number shall not be less than 10. The volumetric flask and other supplies should be soaked in the nitric acid solution of 1..1 overnight, followed by tap water, the background is detected by deionized water cleaning and the method of adding 1% nitric acid solution as the liquid to be tested, and the detection result should be less than the detection limit.

9.5 EDTA anticoagulation tubes cannot be used for blood collection tubes.

9.6 The quality control of the testing process shall be carried out in accordance with the requirements of GBZ/T 295.