This article presents nuclide-specific organ dose rate coefficients for environmental external exposures due to soil contamination assumed as a planar source at a depth of 0.5 g cm⁻² in the soil and submersion to contaminated air, for a pregnant female and its fetus at the 24th week of gestation. Furthermore, air kerma free-in-air coefficient rates are listed. The coefficients relate the organ equivalent dose rates (Sv s⁻¹) to the activity concentration of environmental sources, in Bq m⁻² or Bq m⁻³, allowing to time-integrate over a particular exposure period. The environmental radiation fields were simulated with the Monte Carlo radiation transport codes PHITS and YURI. Monoenergetic organ dose rate coefficients were calculated employing the Monte Carlo code EGSnrc simulating the photon transport in the voxel phantom of a pregnant female and fetus. Photons of initial energies of 0.015–10 MeV were considered including bremsstrahlung. By folding the monoenergetic dose coefficients with the nuclide decay data, nuclide-specific organ doses were obtained. The results of this work can be employed for estimating the doses from external exposures to pregnant women and their fetus, until more precise data are available which include coefficients obtained for phantoms at different stages of pregnancy.

本文提出了由于土壤污染假设为土壤中0.5 g cm ^-2深度的平面源并淹没在污染空气中而导致的环境外照射的核素特异性器官剂量率系数，对于怀孕的女性及其胎儿来说怀孕第24周。此外，还列出了空气比释动系数率。这些系数将器官当量剂量率 (Sv s ^-1 ) 与环境源的活动浓度（以 Bq m ^-2或 Bq m ^-3为单位）联系起来，允许在特定暴露期间进行时间积分。使用蒙特卡罗辐射传输代码 PHITS 和 YURI 模拟环境辐射场。使用蒙特卡罗代码 EGSnrc 模拟怀孕女性和胎儿体素体模中的光子传输，计算单能器官剂量率系数。初始能量为 0.015-10 MeV 的光子被认为包括轫致辐射。通过将单能剂量系数与核素衰变数据折叠，获得核素特异性器官剂量。这项工作的结果可用于估计孕妇及其胎儿的外部暴露剂量，直到获得更精确的数据，其中包括针对怀孕不同阶段的体模获得的系数。