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2. 2. ISO Guide 34, “General Requirements for the Competence of Reference Material Producers”, 2009, ISO, Geneva.
3. 3. ISO/IEC 17025, “General Requirements for the Competence of Calibration and Testing Laboratories”, 2005, ISO/IEC, Geneva.
4. 4. Preventing Disease through Healthy Environments, “Action is Needed on Chemicals of Major Public Health Concern”, 2010, WHO, Geneva.
5. Urban population exposure to lead and cadmium in east and south-east Asia