What test procedure should the laboratory perform to determine compliance with toxics in packaging laws?
It is important to note that the goal of analytical testing is to determine the total concentration of the four regulated metals. For any analytical method to accurately measure the total concentration of metal, the metal must be completely liberated from the matrix. To achieve this, the matrix must be completely digested, dissolved, or broken down. Therefore, proper sample preparation is critical to obtain meaningful results. The choice of sample preparation depends on the type of sample (matrix). All methods used must carefully document the amount of sample digestion, with 100% dissolution as the goal. Sample Preparation Methods Plastics, Some Inks: Many labs use EPA Methods 3050B or 3051 for sample preparation. These methods are described as providing “total metals;” however, the methods were designed for hazardous waste and site characterizations. For the purposes of product or package component testing, the goal is to determine the true presence and total concentration of metals i
