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In disaster response of water-soaked objects,microbial contamination by bacteria and fungi is a serious problem, especially with objects that are left for a long time before recovery. Early response is the best way for the rescue of affected objects,but in the severe tsunami damage over extremely vast areas affected by the Great East Japan Earthquake in March 2011,many paper-based objects including paintings had been left for a month or occasionally for months before they were rescued. In some cases, there was much fungal damage on such objects, although, as a whole, seawater-soaked paper objects seemed to have less fungal damage than those soaked in fresh (rain or river)water. But there were cases in which severe fungal infestation was seen on paintings that had been left for months. As such objects were occasionally contaminated by wastes, treatments with germicides (which also have fungicidal effects) such as EO (ethylene oxide) or PO (propylene oxide)were considered. However, it was expected that such fumigants might react with water or chloride which is included in seawater to generate highly toxic ethylene chlorohydrin (ECH) or glycols which can attract water. Therefore the risk of generation of such chemical residues in seawater-soaked paper objects and books was investigated, partly with those actually affected by tsunami in Iwate prefecture. Some samples were dried before fumigation while others were kept wet.Consequently, ethylene chlorohydrin (ECH)and propylene chlorohydrin (PCH)were under detection level in most of the dried paper samples. But 20-50ppm of ECH was detected in books which were EO-fumigated in wet condition, and 10-20ppm of PCH was detected after POfumigation in wet condition. About 40-70ppm of glycols (ethylene glycol (EG)or propylene glycol (PG))were detected even in samples fumigated in dried condition, and much more glycols (100-400ppm of EG or 250-600ppm of PG)were detected in books fumigated in wet condition. As a whole,generation of chlorohydrin and glycols was less in samples fumigated in dried condition and the residual levels of the chemicals did not seem to be highly risky compared to the recommended residual limits set by FDA, US (1978). Therefore, it is recommended to fumigate objects in well-dried condition if such sterilization is necessary.