ASTM C927-80 Standard Test Method for Lead and Cadmium Removal from the Lip and Mouth Area of ​​Glass Cups Externally Decorated with Ceramic Glass Enamel

The American Society for Testing and Materials (ASTM) standard "ASTM C927-80 Standard Test Method for Lead and Cadmium Extraction from the Lip and Mouth Area of ​​Glassware Decorated with Ceramic Glass Enamel on the Exterior" describes a test method for determining lead and cadmium extracted by acetic acid from the lip and mouth area of ​​glassware decorated with ceramic glass enamel on the exterior and used for drinking purposes. The extraction procedure can be expected to accelerate the release of lead and cadmium from the decorated area and, therefore, to serve as a severe test that is unlikely to be matched under actual conditions of use of such glassware. This test method is specific for lead and cadmium.

For the purposes of this standard, the following terms and definitions apply:

• Ceramic glass decorations refer to ceramic glass enamels fused to glassware at temperatures above 425 degrees to create a decoration.
• Ceramic glass enamels (also ceramic enamels or glass enamels) are predominantly colored, silicate glass fluxes used to decorate glassware.
• The lip and mouth area is that part of a drinking vessel that extends 20 mm below the mouth on the outside of the specimen.

In performing the test, lead and cadmium are removed from the lip and edge region of the article under test by infiltration with a 20 percent acetic acid solution for 24 hours at 24 to 4 degrees and measured by atomic absorption spectrophotometry using special hollow cathode or electrodeless discharge lamps for lead and cadmium, respectively. The results are reported as micrograms per milliliter (ppm) removed relative to the internal volume of the glass article.

The heavy metals, lead and cadmium, are known to cause serious health effects in humans when consumed in excess. Therefore, it is important to measure the amount that can be removed from an area of ​​a glass drinking vessel that comes into contact with the lip. Although the amount of lead and cadmium removed by this test method is by no means representative of the amount of metals removed by actual lip contact, the relative magnitude of metals removed from one test sample relative to another test sample provides an effective means of discrimination.

There is no interference since special hollow cathode lamps or electrodeless discharge lamps are used for lead and cadmium.

The following equipment is mainly used in these tests:

• The atomic absorption spectrophotometer is equipped with a 102 mm single-slot or Boling burner head and a digital concentration readout, if available. This instrument should have a sensitivity of approximately 1 µg/mL lead for 0,5 percent absorbance and approximately 1 µg/mL cadmium for 0,025 percent absorbance. Operating conditions specified in the instrument manufacturer's analytical methods manual are used.
• Hollow cathode or electrodeless discharge lead lamp tuned to 283,3 nm.
• Hollow cathode or electrodeless discharge cadmium lamp tuned to 228,8 nm.
• Glassware made of chemically resistant borosilicate glass for use in preparing and storing reagents and solutions and as test sample containers.
• The detection limits for lead and cadmium should be determined and reported for each instrument. In this test method, the detection limit is defined as twice the mean noise level at 0 µg/mL. Representative detection limits should be approximately 0,01 to 0,03 µg/mL for lead and 0,0005 to 0,0010 µg/mL for cadmium.

In preparing the sample, six identical units are taken and each is rinsed with detergent water. They are then rinsed with tap water, then with distilled water and air dried. Each unit is marked 7 mm below the mouth. The internal volume of each substance is recorded in millilitres by filling it through a graduated cylinder so that it overflows by about 6 to 7 mm. Each substance is marked 20 mm below the mouth, preferably in an undecorated area. The substance is inverted into a suitable laboratory glassware container whose diameter is not less than 1,25 and not more than 2,0 times the diameter of the test specimen at the mouth. A solution of 20 per cent acetic acid is carefully added through a graduated cylinder to the 4 mm mark. The volume of solution used is recorded. If possible, the glassware containers are covered to prevent evaporation and to protect them from contamination. They are left in the dark at room temperature (20 to 24 degrees) for 24 hours. After a 24-hour filtration period, the article is removed and lead and cadmium are determined by atomic absorption. The lead and cadmium found are recorded in micrograms per millilitre.

There is a possibility of significant evaporation. Before the material is removed, it should be determined whether acetic acid seepage is significantly below the 20 mm mark. If so, sufficient acetic acid solution should be added to bring the seepage solution back to the 20 mm mark.

Our organization has a strong staff that closely follows the developments in the world in the field of science and technology and constantly improves itself. Among the numerous test, measurement, analysis and evaluation studies provided for businesses in various sectors, there are also test services in accordance with the standard "ASTM C927-80 Standard test method for lead and cadmium removed from the lip and mouth area of ​​glass cups decorated externally with ceramic glass enamel".