Doctors’ advice on chemical risks; politics, science and the US EPA; safer flame retardants; and more // Recent news highlights (July 2014)July 9, 2014 at 10:55 am | Posted in 5&5 News & Science | Leave a comment
Tags: American College of Obstetricians and Gynecologists, EPA, risk assessment, toxic chemicals
Chemical news: recent
Education about chemical risks | Why doctors don’t talk to pregnant women about toxic chemicals. Reducing pregnant women’s exposure to environmental toxins was recently deemed “critical” by the American College of Obstetricians and Gynecologists to prevent birth defects and other fetal health problems. But a survey published this week of more than 2,500 physician members of that medical group found that fewer than one in five obstetrician-gynecologists ask their pregnant patients about any exposure they’ve had to unsafe levels of toxic chemicals. (Boston Globe)
Politics and risk assessment | How politics derailed EPA science on arsenic, endangering public health. The EPA has been prepared to say since 2008, based on its review of independent science, that arsenic is 17 times more potent as a carcinogen than the agency now reports. But can it formally complete its assessment of arsenic’s toxicity? No. (Center for Public Integrity).
More politics and risk assessment | Why 28 years have passed since the EPA’s last chemical risk review. The EPA’s in-depth report on trichloroethylene, released after a two-year analysis, shows that long-term exposure to TCE can cause cancer and other health issues, and recommends that workers take serious precautions if they must use TCE. The problem is, this is the first final risk assessment for a chemical issued by the EPA since 1986. (Al Jazeera)
Safer chemicals, flame retardants | Searching for safer chemicals: new EPA flame retardants report highlights the dilemmas. When a widely used chemical is identified as an environmental health hazard and targeted for phase-out and elimination, among the most challenging questions for those involved with using and making such a chemical are: What to use instead? and Will the replacement be safe? The US Environmental Protection Agency’s (EPA) report identifying alternatives to the flame retardant hexabromocyclododecane (HBCD) illustrates how difficult those questions can be to answer. (The Pump Handle)
Flame retardants | Kaiser will no longer buy furniture treated with flame-retardant chemicals. The decision applies to all Kaiser facilities across eight states, including Washington and Oregon, and the District of Columbia. “We want manufacturers to shift to new products that don’t contain harmful chemicals,” says Kathy Gerwig, a vice president and environmental stewardship officer for Kaiser. (The Columbian)
Higher PFOA, lower birth weight; abandoning gavage; and more // June science digest #2 (nonhuman and policy research)July 8, 2014 at 12:45 pm | Posted in 5&5 News & Science | Leave a comment
Tags: BPA, Foetal development, PFOA
June Science Digest #2:
Nonhuman and policy research
Foetal development, PFOA | Systematic Review of Nonhuman Evidence for PFOA Effects on Fetal Growth. Analysis of twenty-one studies yields an estimate that exposure of pregnant mice to increasing concentrations of PFOA is associated with a decrease in mean pup birth weight of -0.023g (95% CI: -0.029, -0.016) per 1-unit increase in dose (mg/kg BW/day), providing evidence that PFOA does affect foetal development in the animal model.
Research methods, EDCS | Should oral gavage be abandoned in toxicity testing of endocrine disruptors? Review enumerating several reasons why gavage is not appropriate for the assessment of EDCs using bisphenol A (BPA) as a main example. For example, whereas human dietary exposures interact with the oral mucosa, gavage exposures avoid these interactions, leading to dramatic differences in absorption, bioavailability and metabolism with implications for toxicokinetic assumptions and models.
Neural development, BPA | Newborn mice exposed prenatally to bisphenol A show hyperactivity and defective neocortical development. Observations of newborn mice prenatally exposed to 20 and 200 micrograms BPA kg/day revealed abnormal neuronal distribution and layer formation, hypoplasia of layer 6b, and abnormal dopaminergic neuronal projections in the neocortex. Further, the newborn mice exhibited hyperactivity. These findings suggest that prenatal BPA exposure induces neurobehavioral toxicity associated with abnormal dopaminergic neuronal projections, and abnormal corticogenesis and lamination.
Diabetes, BPA | Exposure to Bisphenol-A during Pregnancy Partially Mimics the Effects of a High-Fat Diet Altering Glucose Homeostasis and Gene Expression in Adult Male Mice. The group of mice exposed to BPA started to gain weight at 18 weeks old and caught up to the mice on a high-fat diet before week 28. The BPA group as well as the HFD and HFD-BPA ones presented fasting hyperglycemia, glucose intolerance and high levels of non-esterified fatty acids (NEFA) in plasma compared with the Control one. Glucose stimulated insulin release was disrupted, particularly in the HFD-BPA group.
PFCs and asthma, phthalate exposure and pre-term birth, plus more // June 2014 science digest #1 (human research)July 7, 2014 at 11:25 am | Posted in 5&5 News & Science | Leave a comment
Tags: asthma, autism, epidemiology, healthcare, pesticide exposure, PFCs, phthalates, premature birth
June Science Digest #1:
Neonatal phthalate exposure in healthcare environments | A Longitudinal Study of Urinary Phthalate Excretion in 58 Full-Term and 67 Preterm Infants from Birth through 14 Months. In this study of hospitalised neonates, the majority of PT (80%) infants and approximately one third of healthy FT newborns (30%) were exposed to phthalates during early life at a potentially harmful level according to EFSA’s recommended limits on daily exposure (a level set for adults).
Child phthalate exposure in educational environments | Phthalate Exposure and Risk Assessment in California Child Care Facilities. Approximately 13 million U.S. children less than 6 years old spend some time in early childhood education (ECE) facilities. The results of this risk assessment indicate that between 8 and 9 children out of 10 in California ECE facilities are exposed to dibutyl phthalate at levels exceeding reproductive health benchmarks, and about 1 in 10 children less than 2 years old are exposed to DEHP at levels exceeding cancer benchmarks.
Childhood asthma, PFCs | Perfluoroalkyl Chemicals and Asthma among Children 12-19 Years of Age: NHANES (1999-2008). This cross-sectional study provides some evidence for associations between exposure to PFCs and asthma-related outcomes in children: in multivariable adjusted models, PFOA was associated with higher odds of ever having received a diagnosis of asthma, whereas for PFOS there were inverse relationships with both asthma and wheezing..
Autism, pesticide exposure | Neurodevelopmental Disorders and Prenatal Residential Proximity to Agricultural Pesticides: The CHARGE Study. Gestational exposure to several common agricultural pesticides can induce developmental neurotoxicity in humans, and has been associated with developmental delay and autism. This study of ASD strengthens the evidence linking neurodevelopmental disorders with gestational pesticide exposures, and particularly, organophosphates and provides novel results of ASD and DD associations with, respectively, pyrethroids and carbamates. (Coverage in Scientific American.)
Pre-term birth, phthalates | Variability in urinary phthalate metabolite levels across pregnancy and sensitive windows of exposure for the risk of preterm birth. Urinary phthalate metabolite levels were moderately variable over pregnancy. Nonetheless, levels measured at various time points were associated with increased odds of preterm birth, the strongest associations being measured at the beginning of the third trimester.