A study claiming that low doses of bisphenol A (BPA) and bisphenol S (BPS) increased brain-cell growth in embryonic zebrafish—which later exhibited hyperactive behaviors as larvae—has urged health authorities to reconsider the use of linear dose-response relationships to set tolerable daily intake levels. Cassandra Kinch, et al., “Low-dose exposure to bisphenol A and replacement bisphenol S induces precocious hypothalamic neurogenesis in embryonic zebrafish,” Proceedings of the National Academy of Sciences, January 2015. After exposing embryonic zebrafish to the two substances at levels (0.0068 µM) similar to those found in rivers that supply two major urban centers, University of Calgary researchers reported that BPA and BPS caused “180% and 240% increases, respectively, in neuronal birth (neurogenesis) within the hypothalamus, a highly conserved brain region involved in hyperactivity.” This increased neurogenesis apparently relied not on estrogen receptors as predicted, but on “androgen receptor-mediated up-regulation of aromatase.” Based on these results, the study’s authors…
Category Archives Scientific/Technical Items
Researchers with the University of California, San Diego, have reportedly linked a sugar molecule found in red meat to the development of spontaneous cancers. Annie N. Samraj, et al., “A red meat-derived glycan promotes inflammation and cancer progression,” Proceedings of the National Academy of Sciences, January 2015. According to a December 29, 2014, press release, N-glycolylneuraminic acid (Neu5Gc) is present in most mammals but not humans, who consume bio-available forms of the molecule from beef, pork and lamb. Building on previous work hypothesizing that Neu5Gc can cause chronic inflammation when absorbed by the human body, the study authors fed the sugar molecule to mice genetically engineered to suppress Neu5Gc. The results not only showed that these mice developed antibodies to Neu5Gc that contributed to systemic inflammation, but that the incidence of spontaneous tumor formation increased fivefold, with Neu5Gc accumulating in the tumors. “Until now, all of our evidence linking Neu5Gc to…
A University of Utah study has reportedly claimed that female mice fed fructose and glucose monosaccharides in proportions similar to the amount of high-fructose corn syrup (HFCS) in human diets “had death rates 1.87 times higher than females on [a] sucrose diet” and “produced 26.4% fewer offspring.” James Ruff, et al., “Compared to Sucrose, Previous Consumption of Fructose and Glucose Monosaccharides Reduces Survival and Fitness of Female Mice,” The Journal of Nutrition, March 2015. Funded by the National Institutes of Health and the National Science Foundation, the study apparently builds on 2013 research concluding that “when mice were fed either a diet with 25 percent calories in the form of added fructose and glucose monosaccharides or 25 percent calories from starch, females died at twice the normal rate and males were a quarter less likely to hold territory and reproduce.” Although the new study did not find any differences in male mice…
A University of California, San Diego, study has reportedly claimed that the brains of obese children “literally light up differently when tasting sugar,” according to a December 11, 2014, press release. Kerri Boutelle, et al., “Increased brain response to appetitive tastes in the insula and amygdala in obese compared to healthy weight children when sated,” International Journal of Obesity, December 2014. Researchers apparently scanned the brains of 10 obese and 13 healthy weight children “while they tasted one-fifth of a teaspoon of water mixed with sucrose (table sugar).” The results evidently showed that the obese children “had heightened activity in the insular cortex and amygdala, regions of the brain involved in perception, emotion, awareness, taste, motivation and reward.” As the lead author explained, “The take-home message is that obese children, compared to healthy weight children, have enhanced responses in their brain to sugar. That we can detect these differences in…
A recent study has claimed that children born to women whose urinary phthalate levels during pregnancy were in the top quartile of their study cohort had lower intelligence-quotient (IQ) test scores at age 7 than their peers born to women in the quartile with the lowest exposure. Pam Factor-Litvak, et al., “Persistent Associations between Maternal Prenatal Exposure to Phthalates on Child IQ at Age 7 Years,” PLoS ONE, December 2014. According to Columbia University researchers, who analyzed data from 328 women and their 7-year-old children from the Columbia Center for Children’s Environmental Health (CCCEH) longitudinal birth cohort, “child full-scale IQ was inversely associated with prenatal urinary metabolite concentrations of DnBP [di-n-butyl phthalate] and DiBP [di-isobutyl phthalate].” Using the fourth edition Weschler Intelligence Scale for Children, the study purportedly found “significant inverse associations… between maternal prenatal metabolite concentrations of DnBP and DiBP and child processing speed, perceptual reasoning and working memory;…
Researchers with Seoul National University have published a study allegedly finding that people who drank soy milk from cans containing bisphenol A (BPA) exhibited a statistically significant increase in blood pressure. Sanghyuk Bae and Yun-Chul Hong, “Exposure to Bisphenol A From Drinking Canned Beverage Increases Blood Pressure,” Hypertension, December 2014. Involving 60 adults older than age 60, the study tracked blood pressure and urinary BPA levels over the course of three visits, during which participants consumed soy milk from either two glass bottles, two cans or one glass bottle and one can. Not only did urinary BPA increase by approximately 1600 percent in volunteers who consumed canned soy milk as opposed to soy milk from glass bottles, but systolic blood pressure also increased by approximately 4.5 mm Hg. “Because these results confirm findings from other studies, doctors and patients, particularly those with high blood pressure or heart disease, should be…
A study led by University of California, Davis, toxicologist Michael Denison and CertiChem, Inc. founder George Bittner has allegedly found that some hard, clear thermoplastic resins made without bisphenol A (BPA) still release chemicals with estrogenic activity (EA). George Bittner, et al., “Chemicals having estrogenic activity can be released from some bisphenol a-free, hard and clear, thermoplastic resins,” Environmental Health, December 2014. According to the study, which used in vitro assays “to quantify the EA of chemicals leached into ethanol or water/saline extracts of fourteen unstressed or stressed (autoclaving, microwaving, UV radiation) thermoplastic resins,” four types of resin “leached chemicals having significant levels of EA.” In particular, the authors noted that UV radiation increased the probability that certain thermoplastic resins would leach chemicals with detectable EA levels. However, the study stopped short of assigning any human health effects to the consumption of these chemicals, as no scientists or other entities “have…
A new study has purportedly found that “urinary phthalate metabolites were associated with increased oxidative stress biomarkers” in a population of 482 pregnant women. Kelly Ferguson, et al., “Urinary Phthalate Metabolites and Biomarkers of Oxidative Stress in Pregnant Women: A Repeated Measures Analysis,” Environmental Health Perspectives, November 2014. In addition to measuring nine phthalate metabolites at 10, 18, 26, and 35 weeks gestation as well as delivery, researchers with the University of Michigan and Harvard Medical School analyzed urinary levels of 8-hydroxydeoxyguanosine (8- OHdG) and 8-isoprostane as biomarkers of oxidative stress. According to the results, “all phthalate metabolites were associated with higher concentrations of both biomarkers,” with mono-benzyl phthalate (MBzP), mono-n-butyl phthalate (MBP), and mono-isobutyl phthalate (MiBP) showing the strongest association with both outcome measures. “Increases in oxidative stress biomarkers in pregnant women have been associated with pregnancy loss, preeclampsia, preterm birth, and fetal growth restriction,” note the study’s authors. “These…
University of California, San Diego, researchers have presented a study at the American Heart Association’s Scientific Sessions 2014, claiming that working-age men who consumed higher amounts of trans fat “had significantly reduced ability to recall words.” According to a November 18, 2014, press release, the study analyzed dietary data from 1,000 healthy men younger than age 45 and asked them to complete a word memory test. The results evidently showed that “each additional gram a day of trans fats consumed was associated with an estimated 0.76 fewer words correctly recalled.” Participants who consumed the most trans fat remembered 11 fewer words than adults who ate the least trans fat, a 10 percent reduction in words remembered. “Trans fats were most strongly linked to worse memory, in young and middle-aged men, during their working and career-building years,” the lead author was quoted as saying. “From a health standpoint, trans fat consumption…
A study of national poison control center data has reported that public and health care providers filed 5,156 incidents of energy drink exposure between October 2010 and September 2013, with 40 percent of cases involving children younger than age 6. Presented at the American Heart Association’s Scientific Sessions 2014, the new research warned that among cases with major outcomes, “cardiovascular effects (including an abnormal heart rhythm and conduction abnormalities) were reported in 57 percent of cases, and neurologic effects (seizures, including status epilepticus) in 55 percent.” The study also identified moderate or major health outcomes in 42 percent of cases involving energy drinks mixed with alcohol and 19 percent of cases involving alcohol-free energy drinks. Based on these findings, the researchers have evidently called for additional labeling to educate consumers about “energy drinks’ high caffeine content and subsequent health consequences.” “The reported data probably represent the tip of the iceberg,” said…
