The food additive polyvinylpolypyrrolidone is approved for use as a filter aid. The water-soluble substances test of polyvinylpolypyrrolidone often shows poor reproducibility. The instruction “boil gently while stirring using a stirrer” was considered critical, and so this issue was examined. The results showed that the use of a combination of both an oil bath and a stirrer provided good reproducibility without decomposition or other problems.
This article provided a scientific basis for determining whether liver hypertrophy, a common change in the liver induced by xenobiotics in toxicological studies, is an adaptive or adverse event. To maintain homeostasis in the whole organism, the liver frequently responds to xenobiotic exposure by increasing metabolic capacity via nuclear receptor activation. The resuiting hepatic adaptive responses (hepatocellular hypertrophy and increased relative liver weight) are potentially beneficial to the organism in providing increased capacity to respond to chemical-induced stress. However, excessive responses should be recognized as adverse. Practically, hepatocellular hypertrophy leading to the following alterations should be considered adverse: 1) hepatocellular degeneration/ necrosis, whether or not accompanied with inflammatory reaction, 2) changes indicating damage to biliary tracts, 3) disruption of fat metabolism, 4) pigmentation, 5) deviation from typical localization or morphological features of hypertrophied hepatocytes.
We surveyed the concentration of radioactive cesium in foods purchased at markets in areas where possible contamination has been a concern after the Fukushima accident. In fiscal years 2012 and 2013, we surveyed 1,735 and 1,674 foods, respectively, using a NaI (Tl) scintillation spectrometer for the screening test and a γ-ray spectrometer with a germanium semiconductor detector for the final test. Only 3 and 4 samples (0.2% of our total samples) exceeded the regulatory limit (100 Bq/kg) for radioactive cesium in fiscal years 2012 and 2013, respectively. Our surveillance indicates that the pre-shipment monitoring of foods by local governments has been working effectively.
An interlaboratory study was performed to evaluate a migration test method of antimony (Sb) and germanium (Ge), based on the Japanese Food Sanitation Law for food- contact polyethylene terephthalate. Eighteen laboratories participated, and quantified Sb and Ge in three test solutions as blind duplicates using graphite furnace atomic absorption spectrometry (GF-AAS), inductively coupled plasma-optical emission spectrometry (ICP-OES) or induced coupled plasma-mass spectrometry (ICP-MS). Statistical analysis revealed that the trueness, repeatability and reproducibility were 98–107%, 1.7–7.5% and 2.0–18.8% by using GF-AAS and ICP-OES. The performance of these methods is sufficient for testing the specifications. The performance parameters of ICP-MS were 99–106%, 0.7–2.2% and 2.2–10.5%, respectively. ICP-MS is available as an alternative measuring method. However, in some laboratories, the quantitative values of Sb were higher than the addition levels. We found that Sb in working solutions is absorbed on glass vessels. Careful control of concentration in working solutions is required for Sb analysis.