1. Scope

1.1 This test method is designed to quantify the amount of total extractable accelerators in natural rubber latex (NRL) and nitrile gloves. Three common classes of rubber accelerators, the mercaptobenzothiazole (MBT), thiuram, and thiocarbamate type compounds can be detected and quantified by this method. If the specific rubber accelerator(s) present in the glove material is not known, quantification is based on zinc dibutyldithiocarbamate (ZDBC) equivalents. This method will not detect all potential rubber accelerators, including mercaptobenzothiazole disulfide, dimorpholine, thioureas and diphenyl diamine.

1.2 For the purpose of this test method, the range of chemical accelerator measurement is based on the limit of detection (LOD) established in the performing laboratory.

1.3 This test method should be performed by experienced analysts or under the supervision of those experienced in the use of spectroscopy and working with organic solvents.

1.4 This test method has not been validated for measurement of long chain dithiocarbamates or accelerators from other rubber products, such as lubricated condoms (1).2 Although this assay has been reported in the literature for the evaluation of accelerator levels in condoms, further validation for accelerator measurement from other rubber products is required by the testing laboratory prior to use.

1.5 This test method is not designed to evaluate the potential of rubber materials to induce or elicit Type IV skin sensitization reactions (for Type IV skin sensitization reactions see Test Method D6355). Total extractable accelerator content does not reflect bioavailablity of individual accelerators that are detected and measured by this method. This test method should be used to test and measure the total residual chemical accelerator level in NRL and nitrile gloves under controlled laboratory conditions, and should not be used to describe, appraise, or assess the hazard or risk of these materials or products under actual in-use conditions.

1.6 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.7 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.8 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

ASTM D7558 - 09(2024)

Standard Test Method for Colorimetric/Spectrophotometric Procedure to Quantify Extractable Chemical Dialkyldithiocarbamate, Thiuram, and Mercaptobenzothiazole Accelerators in Natural Rubber Latex and Nitrile Gloves

Current

Published:

1 Sep 2024