HarmoNIES No.1

"The NIES CRM program will continue to support the accuracy of environmental analysis by providing a wide range of environmental CRMs. " 

 
What if Measurement Scales Differed Depending on the Person?

 
Seven Team Members Producing Environmental CRMs

The environmental CRMs are produced by various research institutes around the world including NIES. All institutes pursue to improve the accuracy of chemical analysis of environmental samples but the largest difference between NIES and others might be the size of the team – the NIES CRM program comprises only seven members. 
  The program runs with a small number of staff paying close attention to the CRMs’ entire production processes from material selection and sampling; material processing (i.e., drying, powdering, sieving, blending, bottling, statistical progressing); and ending with certification in accordance with ISO 17034 (see column). No wonder it takes at least three years to complete this entire process! The CRMs program also takes advantage of obtaining valuable information from experts inside and outside NIES to produce variety of environmental CRMs — NIES has many experts from various disciplines in the field of environmental research. 

Characteristics of NIES CRMs – Pursuing Nearly Natural CRMs

On the contrast to highly-pure reagent containing specific elements and compounds, environmental samples are often complicated mixtures of elements and compounds requiring  appropriate measurement approaches depending on the analytical purposes. For example, hair contains both organic and inorganic mercury species that have become entrapped via different mechanisms. If concentrated chemical is added during the material processing of CRM production, it will not be entrapped to the CRM as in the nature, and the data obtained using the CRM may be incorrect even when measured in a defined approach. In this respect, it is important that CRMs are closer to natural substances and this is why NIES uses only natural substances to prepare CRMs that have been adapted for domestic and international environmental regulations.
  All CRMs are prepared to meet the global standards (International Organization for Standardization, ISO) and are registered to the international reference materials database (COde d'indexation des MAtériaux de Référence, COMAR). The CRM program has such an uncompromising approach for producing CRMs ensuring the accuracy control and traceability of environmental analyses. The following paragraphs describes two of distinctive NIES CRMs, "Rice Flour-Unpolished" and "Typical Japanese Diet", and how they obtain nearly natural samples.

 
Rice Raised at NIES

NIES CRM No.27 Typical Japanese Diet is of great importance for research on chemical substances accumulated into human body from the diet. The dietary intake of contaminant elements, such as arsenic, cadmium, and lead, has been assessed in various research. Japan has a rich food culture that varies considerably by geographical area from the North to the South, from the coast and river to the mountainous inland. To produce the CRM, 29 households from 23 prefectures, from Hokkaido to Okinawa, were selected taking into consideration age and gender. Each household prepared meals in duplicate diet method over three days each in spring and autumn. The households prepared total of 522 meals weighing 60kg including miso soup, grilled fish, sushi, deep-fried pork, snacks, beverages and drinking water. These were all sent to NIES in frozen state to have them freeze-dryed to grind and homogenize, and then bottled. 

 Future Insights

 Forty years have passed since the start of the CRM program, and their scientific challenge continues pursuing to improve the accuracy on chemical analysis of environmental samples and to develop new CRMs.
  The demand for environmental CRMs diversifies as the environment and social conditions changes and as analytical technologies advances. The CRMs are also expected to have a greater variety and values, such as isotopic compositions. The NIES CRM program will continue to support the accuracy of environmental analysis by providing a wide range of environmental CRMs.

 *Reference: Ministry of Health, Labour and Welfare (MHLW) (2010) Partial Revision of Specification and Standards for Food, Food Additives, etc. (Department of Food Safety, 0408 No.2) (in Japanese)