Ecological risk assessment for perfluorooctanoic acid in soil using a species sensitivity approach.

Perfluorooctanoic acid (PFOA) is one of the persistent organic pollutants that has been listed in Annex A of the Stockholm Convention and has attracted attention owing to its endocrine-disrupting properties. However, there is currently little information available regarding the soil ecotoxicity of PFOA and the associated ecological risks. Accordingly, in this study, we sought to assess the soil ecological risk of PFOA based on a probabilistic approach using data obtained from multispecies bioassays and soil toxicity assessments, from which we generated soil species sensitivity distributions and estimated soil protective concentrations for PFOA. Using the latter distributions, we also undertook a probabilistic ecological risk assessment. On the basis of acute and chronic toxicity estimates obtained from bioassays involving eight soil-associated organisms from six diverse taxonomic groups, we could deduce that PFOA poses a negligible risk to soil ecosystems. However, we also found that this chemical may be more toxic than some of the established endocrine-disrupting chemicals such as bisphenol A, nonylphenol, and methylparaben, thereby indicating that further in-depth studies would be necessary to obtain a better understanding of the toxic potential of this chemical in the soil environment.

Do the Emotions of Middle-Income Mothers Affect Fetal Development More Than Those of High-Income Mothers?-The Association between Maternal Emotion and Fetal Development.

This study examines the relationship between the emotions of mothers and fetal development and explores the modifying effect that family income has on this relationship. Socio-demographic information, maternal depression, stress, positive and negative emotions, and maternal-fetal attachment data were collected at 16-20 weeks of pregnancy. Data on fetal body weight and biparietal diameter indicating fetal development were collected at 33-35 weeks to observe the longitudinal effects of mothers' emotions on fetal development. We divided subjects into two groups: those with more than 150% of the median income were classified as the high-income group and less than 150% as the middle-income group. T-test, correlation analysis, and multiple regression analysis on maternal emotional status and fetal development were performed for each group. A positive correlation was found between maternal-fetal attachment and negative emotion that was associated with the biparietal diameter and fetal body weight only in the middle-income group. Results of the multiple regression analysis were statistically significant, indicating that maternal-fetal attachment was associated with fetal weight. These results show that the management of subjective emotion is associated with healthy development of the fetus and contributes to health equity.

Changes in intracranial volume and cranial shape in modern Koreans over four decades.

OBJECTIVES: This study investigated whether there was any secular change in cranial vault morphology among Koreans born between the 1930s and 1970s, a period of dramatic shift in Korea's socioeconomic conditions. MATERIALS AND METHODS: Using three-dimensional MRI volumetry, we obtained the intracranial volume (ICV) and craniometric measurements of 115 healthy Koreans: 58 individuals (32 males and 26 females) born in the 1930s (1926-1936) and 57 (28 males and 29 females) born in the 1970s (1972-1979). RESULTS: The intracranial volume of males was 1502.3 ± 110.3 cm3 for the 1930s group and 1594.1 ± 99.5 cm3 for the 1970s group, and for females, it was 1336.0 ± 53.0 cm3 for the 1930s group and 1425.9 ± 79.6 cm3 for the 1970s group. On average, ICV increased by 94 cm3 in males and by 90 cm3 in females. Cranial measurements for the 1970s group were significantly larger than the 1930s group for both sexes except in female cranial length. Each measurement was significantly correlated with ICV [cranial height (R = 0.720), breadth (R = 0.706), and length (R = 0.531)]. The cephalic index decreased from 0.846 to 0.828 in males, indicating the cranium became narrower relative to the cranial length. In females, the cephalic index increased from 0.831 to 0.850. Sex and birthyear were marginally interrelated in cephalic indices. DISCUSSION: From the 1930s to 1970s, the Korean Peninsula experienced important historical shifts, and we speculate that the consequent shift in socioeconomic status is the most likely factor responsible for Koreans' cranial vault remodeling.