Many people assume that the chemicals in their detergents, floor cleaners, and other household products have undergone rigorous safety testing. But little is known about the potential risks associated with most of the estimated 80,000 chemicals in commerce today.

While industry tries to dispel links to illnesses that go beyond what science can prove, the public is skeptical because companies have a financial stake in showing their products are safe. This leads both sides to look to the federal government for help.

The agency charged with overseeing the safety of chemicals in the marketplace is the Environmental Protection Agency. EPA has the authority to require industry to provide extensive toxicity data for pesticides. But for most other chemicals, EPA must show that a substance is likely to be a risk to human health or the environment in order to require industry to provide safety data. Manufacturers don't often give toxicity data to EPA voluntarily, nor does the agency have the resources to assess tens of thousands of chemicals using traditional in vivo rodent-based studies.

Instead, EPA has turned to computational modeling. One ambitious effort, called ToxCast, aims to screen thousands of chemicals for biological activity using about 600 high-throughput biochemical and cell-based assays. The data are then integrated with existing in vivo animal toxicity data and structure-activity information to predict toxicity.

While all areas of human activity have an impact on the environment, the chemicals industry is often singled out as a particularly poor environmental performer, associated with high energy consumption and the generation of large quantities of toxic waste products.

Thus, as chemical production continues to increase, the global industry faces both economic and environmental pressures, and growing regulatory constraints. Much of the concern revolves around the widespread use of powerful and dangerous solvents.

EU project AQUACHEM ("Transition metal chemistry and catalysis in aqueous media") was established to examine the substitution of dangerous solvents with chemical catalytic processes compatible with water-based media -- and also to provide young scientists with more experience in the field.

The network, led by Italy's National Research Council, is allowing scientists, including those just starting their careers, to conduct research at some of Europe's top laboratories. The project also included labs in the UK, France, Germany, Spain, Hungary and Israel.

Background: The metabolic disruptor hypothesis postulates that environmental pollutants may be risk factors for metabolic diseases. Because insulin resistance is involved in most metabolic diseases and current health care prevention programs predominantly target insulin resistance or risk factors thereof, a critical analysis of the role of pollutants in insulin resistance might be important for future management of metabolic diseases.

Objectives: We aim at critically reviewing the available information linking pollutant exposure to insulin resistance and intend to open the discussion on future perspectives for metabolic disruptor identification and prioritization strategies.

Methods: PubMed and Web of Science were searched for experimental studies reporting on linkages between environmental pollutants and insulin resistance. A total of 23 studies were identified as the prime literature.

Discussion and conclusions: Recent studies specifically designed to investigate the effect of pollutants on insulin sensitivity show a potential causation of insulin resistance. Based on these studies, a table of viable test systems and endpoints can be composed which allows ... insight into what is missing and what is needed to create a standardized insulin resistance toxicity testing strategy. It is clear that current research predominantly relies on top-down identification of insulin resistance-inducing metabolic disruptors and that one of the major future research needs is the development of dedicated in vitro or ex vivo screens to allow animal sparing and time- and cost-effective bottom-up screening.

Using X-ray crystallography to visualize the three-dimensional structure of an enzyme associated with regulating levels of estrogen, a team of National Institutes of Health scientists have discovered new information on how flame retardants may alter estrogen metabolism. Their results suggest one way in which these chemicals may disrupt the body's endocrine system.

Flame retardants are added to foam, textiles, electronics, building materials, and other items to reduce flammability. The new research focuses on tetrabromobisphenol A (TBBPA), currently the most heavily produced flame retardant in the world, and 3-OH-BDE-47, a metabolite of the Penta bromodiphenyl ethers (PentaBDEs), which were widely used prior to 2004 and remain in many long-lived consumer goods. . . .

The new research shows how both TBBPA and 3-OH-BDE-47 can bind to an enzyme known as estrogen sulfotransferase (SULT1E1). This enzyme's job is to bind the major endogenous estrogen 17β-estradiol and add a sulfate molecule to it; the sulfated estradiol is more readily eliminated from the body. "Basically, the flame retardants are going to compete with estradiol for binding to the sulfotransferase," says coauthor Linda Birnbaum, director of the National Institute of Environmental Health Sciences (NIEHS). The result may be to raise levels of estradiol in the body, explains corresponding author, Lars Pedersen of the NIEHS Laboratory of Structural Biology.

The North American river otter (Lontra canadensis) is a biomonitor for organohalogenated compounds (OHCs) associated with a wide range of deleterious health effects in wildlife and humans. We determined concentrations of twenty OHCs in livers of 23 river otters salvaged by the Illinois Department of Natural Resources from 2009 to 2011, determined sex-dependent distribution of OHCs, and compared our results to the reported concentrations of four OHCs in Illinois river otters from 1984 to 1989. Since these contaminants have been banned for over 30 years, we predicted smaller mean concentrations than those previously reported in Illinois otters. We detected eleven of twenty OHCs; PCBs (polychlorinated biphenyls), dieldrin, and 4,4'-DDE (dichlorodiphenyldichloroethylene) were present in the greatest mean concentrations. We report the largest mean concentration of dieldrin to date in the liver of North American river otters (mean: 174, range: 14.4-534 parts per billion wet wt [ppb]). Mean PCB concentrations were significantly higher in males (mean: 851; range: 30-3450 ppb) than females (mean: 282; range: 40-850 ppb; p=0.04). Mean concentrations of dieldrin were greater than those detected in otters from 1984 to 1989 (mean: 90; range: 30-130 ppb; p<0.05). Our results suggest OHC exposure remains a concern. Future research in Illinois should focus on evaluating OHCs exposures, particularly dieldrin, at the watershed level.

The concept of the wet blasting process in parts cleaning and surface finishing is straightforward enough: combine abrasive media with water to form a special slurry, then add regulated compressed air to control the pressure as it is discharged over a surface.

It is a dust-free and static-free process that removes burrs, scale, oxidation and rust, marks, paint, and coatings. It can also remove oils and grease while performing other functions such as preparing the surface for other coatings or processes.

Today, matte finishes are a popular choice for parts-often for both practical and cosmetic reasons. Automated slurry-blasting machines are a great choice for achieving fine, non-directional matte finishes in a single operation. Depending on the application, profiles of less than 4 Ra are possible, and users can choose from various media, including glass beads, ceramic or plastics.

The slurry-blast process virtually eliminates embedded media issues commonly found in dry blasting systems. The water and slurry are recirculated, requiring no drain hookup. The process does not create dust, and chemicals are not required, adding to its appeal for manufacturers committed to limiting their environmental impact.

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See also from Products Finishing, Progress in Replacing Decorative Electroplating Chrome Coatings on Plastics with Physical Vapor Deposition Coatings.