Tissue free water tritium and organically bound tritium in the rice plant acutely exposed to atmospheric HTO vapor under semi-outdoor conditions

Tritium concentration in soybean plants exposed to atmospheric HTO during nighttime and daytime

“…Inside the box during each exposure, the means of relative humidity, temperatures, and solar radiations were in the range of 61.4-94.2 %, 25.1-34.8°C, and 234-678 W m -2 , respectively. It is indicated that the leaf TFWT concentration may reach equilibrium within 1 h at clear weather [12].…”

“…Recently, an increased interest of the fate of tritium in vegetation generated a series of dedicated tritium research because photosynthesis is the first necessary step for the production of organic matter [2,[10][11][12][13]. The existing studies mainly focus on the routine release and short atmospheric HTO exposure at daytime [4,[11][12][13][14][15][16][17][18][19][20][21][22][23][24].…”

“…The existing studies mainly focus on the routine release and short atmospheric HTO exposure at daytime [4,[11][12][13][14][15][16][17][18][19][20][21][22][23][24]. Little information is currently available regarding the tritium uptake and subsequent formation of organically bound tritium (OBT) in plants exposed to elevated levels of atmospheric tritium during the nighttime [24].…”

Apports de la surveillance du centre CEA-Valduc sur la connaissance des transferts de l’eau tritiée atmosphérique dans les différents compartiments de l’environnement

“…L'eau libre des feuilles se charge puis se décharge assez rapidement en tritium, avec une demi-vie biologique de l'ordre de quelques heures pendant la journée, lorsque les végétaux sont temporairement placés dans une atmosphère contenant de la vapeur d'eau tritiée (Kline et Stewart, 1974 ;Dinner et al, 1980 ;Guenot et Belot, 1984 ;Spencer, 1984 ;Choi et al, 2002 ;Davis et al, 2002). Ceci révèle une diffusion de l'eau de l'air vers l'eau contenue dans la plante, principalement à travers les stomates, malgré un flux d'eau essentiellement sortant.…”

Modeling Tritium Transport, Deposition and Re-Emission

“…(Murphy and Corey 1975). A small amount may become organically bound within the plant (Choi et al 2002;Ota and Nagai 2011) but this is small enough so as to be negligible (Sweet and Murphy 1984) and it can be assumed that nearly all absorbed HTO will be re-emitted. Brudenell et al (1997) estimated that this could occur within 48 hr.…”