Vol.3 No.2 2010

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Report : Knowledge for interdisciplinary consilience−174−Synthesiology - English edition Vol.3 No.2 (2010) process, I think I was able to organize my way of thinking at the time I was doing research, and I caught myself saying, “Oh, so that’s what I was thinking!”My research is risk assessment of chemical substances. I had to think of a way to rank the risk reduction measures in Japan according to priority for about 100 thousand industrial chemical substances. To do so, I had to compare the magnitude of the risks of various chemical substances.Risk can be expressed by multiplying the level of exposure and the strength of toxicity. Combining the two data for the distribution of exposure level for all Japanese, and how much increase there is in the incidence rate when the exposure level increases, and then looking at the size of risk of each chemical substance, these become the “necessary information”. However, it was found that the “available information” amongst the “necessary information” were way insufficient.For exposure level, there are several examples of people exposed to extremely high concentrations. For example, there are many examples of extremely high measurements of formaldehyde concentration in a newly built house and short-term daily average values. However, there was hardly any data on long-term annual average values that we wanted to obtain, nor was there data showing the seasonal changes. For toxicity, there were data for no-observed-adverse-effect level of “concentration below which no adverse effect will occur”, but there was no data for dose response function showing “this much incidence rate will occur if there is this much exposure”. Therefore, the current elemental technologies could not be used, and we had to on our own develop and modify the elemental technology.The “existing elemental technologies” that we determined to be “useless”, while they include the ones I recognized after I wrote the paper, were the ones for the risk assessment of chemical substances reflecting the initial demands in society. These elemental technologies were selected when conducting a chemical substance screening, which involved the elimination of no-risk substances amongst the milliard chemical substances. Therefore, the method to achieve that objective was pursued. The elemental technology was developed to find the level that was safe for high concentration exposure, and it was optimized for the work of saying “if this substance is okay at high concentration, then it is safe at ordinary concentration”.The elemental technology thus developed was established by repeated practice. Guidelines and manuals were written, became routine, and the methodology for the initial risk assessment for chemical substances was established.However, what we were trying to do was “risk comparison for several types of chemical substances”, and in a sense, it was a new social demand. The existing elemental technology was inappropriate for this purpose. The existing elemental technology was for a different social demand, because it was a part of the set of elemental technologies optimized for screening assessment. Therefore, we became aware of the gap where we could not use the risk assessment technology for the new demand.We returned to the origin, and started looking at the methodology of which elemental technology was necessary to enable the “comparison of different types of risks” that was the new social demand. This is called “re-synthesis” in “synthesiology”. Rather than measuring only the people with high exposure concentration, we looked at the distribution of annual average values of the individual exposure estimate and the distribution of the environmental concentration estimates in Japan. Rather than looking at one value where anything below it is safe, we looked at the whole picture, and saw that there were various elemental technologies that must be optimized. Development of these elemental technologies is the “strategic development of elemental technologies”. Next, the elemental technologies developed are integrated and synthesized. Then, we enter the phase of “integration and synthesis of various elemental technologies” where we establish the new methodology and put them in practice.The essence of the paper written for Synthesiology was to develop a new methodology and to conduct risk assessment to compare the various types of risks.When I was doing this, I thought about “the trap of the fields of specialty”. It may be extravagant, but the currently existing specialty and research topics were always derived from some past social demands. The “fields of specialties” that were formed became divorced from their origins and went through their unique evolution. For example, they generated academic societies, specialists, guidelines, journals, courses, and textbooks, and became autonomous. However, social demands and societal values are ever changing. In modern society where changes occur dramatically, the specialties fall into autotelism, and I Comparison of different risksScreening assessmentChanges in issues to be solved by risk assessmentof chemical substancesIntegration, synthesisHomeward boundOutward boundStrategic selectionElemental technology aResearchobjective(products)Problem setting(scope)Elemental technology bElemental technology cElemental technology dElemental technology aElemental technology bElemental technology cElemental technology dStrategicselectionIntegration, synthesisResearchobjective(parts)Researchobjective(parts)Researchobjective(parts)Researchobjective(parts)Issuesto besolvedChanges in issues to be solved by risk assessment of chemical substances

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