A recent University of Michigan study has reportedly suggested that phthalates and bisphenol A (BPA) could affect thyroid functioning in humans. John Meeker and Kelly Ferguson, “Relationship Between Urinary Phthalate and Bisphenol A Concentrations and Serum Thyroid Measures in U.S. Adults and Adolescents from NHANES 2007-08,” Environmental Health Perspectives, July 11, 2011. Researchers apparently used thyroid serum measures from 1346 adults and 329 adolescents enrolled in the U.S. National Health and Nutrition Examination Survey to determine that “[g]enerally speaking, greater concentrations of urinary phthalate metabolites and BPA were associated with greater impacts on serum thyroid measures.” In particular, the study found that as urinary metabolite concentrations for di(2-ethylhexyl) phthalate (DEHP) and BPA increased, certain thyroid hormones decreased. “The current study showed the strongest relationship between thyroid disruption and DEHP,” explained a July 12, 2011, University of Michigan press release, which noted that “urine samples in the highest 20 percent of exposure…
Category Archives Scientific/Technical Items
In 2007, a study published in The New England Journal of Medicine generated widespread media coverage for its claims that obesity can be transmitted via social networks, such as friendship, familial relationship or marriage. Details about the study appear in Issue 225 of this Update. The authors wrote additional papers on other personal characteristics, including smoking cessation, happiness and loneliness, concluding in each that a process of contagion or infection within the social network transmits the characteristics and that the transmission occurs up to three steps in the network, thus providing evidence of a “’three degrees of influence’ rule of social network contagion.” A new study published in a lesser-known journal, contends that the authors’ statistical analyses do not support their conclusions. Russell Lyons, “The Spread of Evidence-Poor Medicine via Flawed Social-Network Analysis,” Statistics, Politics, & Policy, Vol. 2, Issue 1 (2011). According to Russell Lyons, an Indiana University mathematician, the 2007…
University of Missouri scientists have reportedly published the first study to examine “serum BPA [bisphenol A] concentrations in an animal model exposed to this chemical via the diet,” as opposed to oral bolus exposure. Paizlee Sieli, et al., “Comparison of Serum Bisphenol A Concentrations in Mice Exposed to Bisphenol A through the Diet Versus Oral Bolus Exposure,” Environmental Health Perspectives, June 6, 2011. After comparing BPA serum concentrations in adult female mice after oral bolus administration or ad libitum feeding, researchers concluded that bolus administration “underestimates bioavailable serum BPA concentrations in animals and therefore, presumably humans than would result from dietary exposure.” According to the study, these results suggest that “exposure via diet is a more natural continuous exposure route than oral bolus exposure, and thus, a better predictor of BPA concentrations in chronically exposed animals and humans.”
The World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) has issued a colorectal cancer report allegedly concluding “that red and processed meat increase risk of the disease.” Part of the groups’ Continuous Update Project, which in 2007 covered 749 papers on colorectal cancer, the 2011 report reviews 263 additional papers examining “the links between colorectal cancer risk and diet, physical activity and weight.” According to a May 23, 2011, press release, the findings provide “convincing evidence that both red and processed meat increase colorectal cancer risk,” while “foods containing fiber offer protection.” Billed by WCRF/AICR as “the most comprehensive and authoritative report on colorectal cancer risk ever published,” the meta-analysis also suggested that “ounce for ounce, consuming processed meat increases risk twice as much as consuming red meat.” WCRF/AICR recommends that “people limit consumption to 18 ounces (cooked weight) of red meat a week – roughly the equivalent of…
A recent study examining national salt-reduction strategies around the world has concluded that such programs are “likely to be one of the simplest and most cost-effective ways of improving public health.” Jacqueline Webster, et al., “Salt Reduction Initiatives Around the World,” Journal of Hypertension, June 2011. The study used existing reviews, literature and relevant websites to identify 32 national salt-reduction initiatives, finding that “the majority of the activity was in Europe.” Twenty-six of the 32 strategies “were led by government, five by nongovernment, and one by industry,” and some were “multifaceted including food reformulation, consumer awareness initiatives and labeling actions.” Of the countries identified as having a salt-reduction strategy, (i) 27 “had maximum population salt intake targets, ranging from 5 to 8 g/person per day,” (ii) 28 “had some baseline data on salt consumption and 18 had data on sodium levels in foods,” (iii) 28 “were working with the food…
Canadian researchers have allegedly detected the presence of Cry1Ab toxin in human blood, raising questions about whether “pesticides associated to genetically modified [GM] foods (PAGMF)” break down during digestion as previously claimed. Aziz Aris and Samuel Leblanc, “Maternal and fetal exposure to pesticides associated to genetically modified foods in Eastern Townships of Quebec, Canada,” Reproductive Toxicology, 2011. The study apparently focused on 30 pregnant and 39 non-pregnant women with no direct or indirect contact with pesticides. The findings evidently showed Cry1Ab toxin—“an insecticidal protein produced by the naturally occurring soil bacterium Bacillus thuringiensis [bt]” and used in GM maize—“in 93% and 80% of maternal and fetal blood samples, respectively and in 69% of tested blood samples from non-pregnant women.” According to the study’s authors, these results suggest “(1) that these toxins may not be effectively eliminated in humans and (2) there may be a high risk of exposure through consumption…
A study presented at the 2011 Pediatric Academic Societies meeting in Denver, Colorado, has evidently suggested an association between prenatal bisphenol A (BPA) exposure and wheezing in childhood. According to a May 1, 2011, press release, researchers followed 367 pairs of mothers and infants, measuring BPA levels in the urine of pregnant woman “at 16 and 26 weeks’ gestation as well as when they delivered their babies,” and asking mothers “every six months for three years… whether their child wheezed.” Although “99 percent of children were born to mothers who had detectable BPA in their urine at some point during pregnancy,” those infants “whose mothers had high levels of BPA during pregnancy were twice as likely to wheeze as babies whose mothers had low levels of BPA.” The researchers noted, however, that the association held true in the youngest group of children only, with no differences in wheezing rates by…
A European study has reportedly raised questions about the impact of low-sodium diets on heart health, finding that people who apparently consumed the least amount of salt did not lower their risk for high blood pressure and, contrary to expectations, increased their risk of death from cardiovascular disease (CVD). Katarzyna Stolarz-Skrzypek, et al., “Fatal and Nonfatal Outcomes, Incidence of Hypertension, and Blood Pressure Changes in Relation to Urinary Sodium Excretion,” Journal of the American Medical Association, May 4, 2011. Researchers based their results on 24-hour sodium excretion measurements taken over a median 7.9 years from 3,700 subjects “randomly enrolled in the Flemish Study on Genes, Environment, and Health Outcomes (1985-2004) or in the European Project on Genes in Hypertension (1999-2001).” The findings from this cohort evidently indicated that while higher sodium excretion aligned with an increase in systolic blood pressure, “this association did not translate into a higher risk of…
A Fred Hutchinson Cancer Research Center study has reportedly found that men with the highest blood percentages of the omega-3 fatty acid known as docosahexaenoic acid (DHA) “have two-and-a-half-times the risk of developing aggressive, high-grade prostate cancer compared to men with the lowest DHA levels,” according to an April 25, 2011, press release. Theodore Brasky, “Serum Phospholipid Fatty Acids and Prostate Cancer Risk: Results From the Prostate Cancer Prevention Trial,” American Journal of Epidemiology, April 2011. Based on data from 3,400 men enrolled in the Prostate Cancer Prevention Trial, the study has also claimed that, contrary to expectations, “men with the highest blood ratios of trans-fatty acids . . . had a 50 percent reduction in the risk of high-grade prostate cancer.” The findings evidently surprised researchers, who expected that the anti-inflammatory properties of omega-3 fatty acids would reduce prostate cancer risk, while trans-fatty acids and the omega-6 fatty acids commonly…
A recent study by the Arizona-based Translational Genomics Research Institute (TGRI) has reportedly identified Staphylococcus aureus in 47 percent of meat and poultry samples obtained from retail stores, with 52 percent of the contaminated samples testing positive for multidrug-resistant S. aureus. Andrew Waters, et al., “Multidrug-Resistant Staphylococcus aureus in U.S. Meat and Poultry,” Clinical Infectious Diseases, April 2011. According to a summary of the study, which received funding from the Pew Charitable Trusts, researchers collected 136 samples of ground beef, chicken breasts and thighs, ground pork and pork chops, and ground turkey and turkey cutlets from 26 retail stores in Chicago, Washington, D.C., Fort Lauderdale, Los Angeles, and Flagstaff. The results purportedly indicated that S. aureus contaminated “a substantial portion of samples from all meat and poultry types (37-77%), with a notable 52% of isolates being multidrug resistant” to antimicrobials such as tetracycline, ampicillin, penicillin, and erythromycin, among others. “The…
