BS ISO 7086-1:2019 pdf download – Glass hollowware in contact with food — Release of lead and cadmium Part 1: Test method
5.1.2 Acetic acid, (CH3COOH), glacial, ρ = 1,05 g/ml.
5.1.3 Acetic acid test solution, with a volume fraction of 4 %.
Add 40 ml of acetic acid (5.1.2) to water (5.1.1) with a one-mark pipette (6.2.4) and dilute to 1 l in a onemark volumetric flask (6.2.5). This solution shall be freshly prepared for use. Proportionately greater
quantities may be prepared.
5.2 Materials and supplies
5.2.1 Paraffin wax with a melting point in the range 56 °C to 58 °C.
5.2.2 Washing agent, commercially available non-acidic manual dishwashing detergent in dilution recommended by a manufacturer.
5.2.3 Silicone sealant, capable of forming a ribbon of sealant approximately 6 mm in diameter.
This sealant shall not leach acetic acid, cadmium or lead to the test solution.
6.1 Analytical techniques
ICP-MS, FAAS and inductively coupled plasma optic emission spectrometry (ICP-OES) are described in Annexes A, B and C, respectively.
GFAAS is also a permitted option.
6.2.1 Assorted laboratory ware, as required, made of borosilicate glass as specified in ISO 3585.
6.2.2 Burette, of capacity 25 ml, graduated in divisions of 0,05 ml, conforming with ISO 385 class B or better.
6.2.3 Covers for the articles under test, for example plates, watch-glasses or Petri dishes of various sizes. Covers shall be opaque if a darkroom is not available.
6.2.4 One-mark pipettes, of capacities 10 ml and 100 ml, conforming with ISO 648, class B or better.
Other sizes as required.
6.2.5 One-mark volumetric flasks, of capacities 100 ml and 1 000 ml, conforming with ISO 1042,class B or better. Other sizes as required.
6.2.6 Precision piston pipettes, typically 1 000 µl and 500 µl.
6.2.7 Straight edge and depth gauge, calibrated in millimetres.
7.1 Priority When selecting samples from a mixed lot of foodware, articles that have the highest surface area/ volume ratio should be prioritized. 7.2 Sample size At least four items shall be measured. Each of the articles shall be identical in size, shape, colour and decoration.
7.3 Preparation and preservation of test samples Samples of ware shall be clean and free from grease or other matter likely to affect the test. Briefly wash the specimens in an aqueous solution at (40 ± 5) °C at hand-hot temperature using tap water containing 1 ml/l of a non-acidic domestic detergent. Rinse in tap water and then in water (5.1.1). Drain and dry either at a temperature of (40 ± 5) °C in a drying oven or by wiping with a new piece of filter paper. Do not use any sample that shows residual staining. Do not handle the surfaces to be tested after cleaning. 8 Procedures
8.1.1 Extraction temperature Conduct the extraction at a temperature of (22 ± 2) °C in the dark.
8.1.2 Leaching Fill each specimen with test solution to 1 mm from overflowing, as measured vertically. Cover the specimen. Leach for (24 ± 0,5) h, or (2 ± 0,1) h depending on the case studied.
8.1.3 Sampling of the extraction solution for analysis Prior to sampling, mix the extraction solution by stirring or another appropriate method that avoids loss of the extraction solution or abrasion of the surface. Remove the amount of the extraction solution required by the considered analytical method with a pipette and transfer it to a suitable storage container. Analyse the extraction solution as soon as possible since there is a risk of adsorption of lead or cadmium on to the walls of the storage container, particularly when Pb and Cd are present in low concentrations.
8.1.4 Drinking rim The drinking rims of glass hollowware shall be tested by marking each of four units (20 ± 1) mm below the rim on the outside. Each item is placed inverted in a suitable laboratory glassware container with a diameter between 1,25 and 2 times that of the item. Add sufficient test solution (5.1.3) to the glassware container to fill to the 20 mm mark on the item. Leave to stand for (24 ± 0,5) h, or (2 ± 0,1) h depending on the considered case, at (22 ± 2) °C (in the dark for cadmium determinations) and protect from excessive evaporation. Carefully cover the portion of the external surface of the article that is not to be tested with melted paraffin wax. Cover any handle present in the drinking rim region to be tested in the same way.BS ISO 7086-1 pdf download.