Development of Analytical Method and Surveillance ofGibberellic Acid in Banana, Cherry, and Kiwi Fruit.

Gibberellic acid (GA) is commonly used as a plant growth regulator in many food crops owing to its essential signaling functions during plant growth and development. In Japan, a threshold for administrative action for GA content of 0.3 mg/kg applies in produce in which maximum residue limits have not been established.

[Estimation of the Distribution of Dietary Exposure to Lead Using Two-Dimensional Monte Carlo Simulation: An Attempt to Apply to Total Diet Samples].

The average dietary exposure to lead (Pb) in male and female Japanese individuals >1 year of age was estimated using 280 total diet samples representing 14 food groups from 10 areas over a two-year period. A probabilistic exposure estimation was performed using a two-dimensional Monte Carlo simulation (2D-MCS) with a Bayesian estimation that consided the uncertainty of the estimation process. The Bayesian estimation was performed using the likelihood function with cumulative distribution function between the lower and upper boundary values for no-detected values.

Quantification of progesterone in beef with marbling using liquid chromatography-tandem mass spectrometry with stable isotope-labelled standards.

Progesterone (P4) is contained naturally in animal tissue, and it is also used as a veterinary drug in cattle for treatment purposes. To assess the risk from P4 residues in beef derived from treated cattle, it is essential to quantify the P4 contained naturally in cattle tissue (endogenous P4). Therefore, we performed a method validation for the quantification of endogenous P4 (method quantification limit = 0.

Behavior of isoprothiolane and fipronil in paddy water, soil, and rice plants after nursery-box or submerged applications.

We investigated the behavior of isoprothiolane and fipronil after nursery-box application and that of isoprothiolane after submerged application in an experimental paddy field. The concentrations of the pesticides and their metabolites were monitored in paddy water, soil, and rice plants. The distribution profile for isoprothiolane mass in the field differed greatly between the nursery-box and submerged applications.

Improved PADDY-Large model including lateral seepage loss from paddy fields to predict pesticide behavior in river basins.

We developed an improved simulation model for predicting pesticide concentrations in river basins based on PADDY-Large, which includes lateral seepage loss of pesticides from paddy fields. Based on the structure of typical Japanese paddy fields, pesticide transport process due to lateral seepage through bunds was modeled as a compartment system consisting of pore water and soil particle. The model was validated with concentrations measured by monitoring paddy pesticides in a tributary of the Sakura River in Japan.