Tag Archives: endocrine disruptors

BADGE, made from BPA, reacts with food.

BADGE, made from BPA, reacts with food.

Jul 19, 2010

Coulier, L, EL Bradley, RC Bas, KCM Verhoeck, M Driffield, N Harmer and L Castle  2010.  Analysis of reaction products of food contaminants and ingredients: Bisphenol A diglycidyl ether (BADGE) in canned foods. Journal of Agricultural and Food Chemistry 58:4873-4882.

Synopsis by Evan Beach

Leftover residues of a compound made from bisphenol A (BPA) for use in food can linings reacts with sugars, proteins and other parts of food to form new molecules, researchers report.

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A main component of food can linings forms new chemicals when it reacts with different parts of food, according to research published in the Journal of Agricultural and Food Chemistry.

BADGE – which is short for bisphenol A diglycidyl ether – is manfactured from bisphenol A and is a building block of certain types of resins that coat food and drink cans. Like its parent compound, BADGE has endocrine disrupting properties.

The researchers from The Netherlands and Great Britain found that BADGE residue left over from manufacturing of the can coating can react with sugars, proteins and other small molecules – for example ethanol in beer.

The findings show how critical it is to understand the extent of chemical migration from resin linings into the can’s contents and what happens to the compounds once they interact with the food and beverage.

This is important because of the implications for food safety. The European Union bases its regulations for how much BADGE can migrate from food primarily on the reaction between BADGE and water.

However, the study’s authors found that the BADGE-water reaction only accounted for as much as 26 percent of the “disappearing” BADGE  they added to samples of canned tuna, apple puree and beer. Some of the remaining BADGE could be detected as BADGE-glucose and BADGE-amino acid reaction products. Even when the additional BADGE products were considered, it was still not possible to account for all of the BADGE added to the food.

The researchers suspect that BADGE can form products with larger, high-molecular-weight carbohydrates, fibers and proteins that would be difficult to detect directly with the methods they used. This was the case for proteins. When the authors mixed BADGE with insulin, a large protein, the BADGE was effectively invisible. But when they broke down the protein into its component parts, then the BADGE products could be detected.

Although large molecules like the insulin-BADGE product would probably be too large to be absorbed by the body at first, it is possible that after they break down into smaller molecules in the stomach, then exposure to BADGE would be likely.

The BPA-like chemical backbone of BADGE was not changed by reactions with food molecules. The authors did not discuss whether the structural similarity of these products to BADGE and BPA might lead to similar harmful effects attributed to BPA or if the BADGE products might be related to levels of BPA that have been detected in most of the U.S. population.

For the study, BADGE was added to two types of canned food – tuna in sunflower oil and apple puree – and three drinks – an ale, a stout, and a lager. Spiked and nonspiked controls were recanned, homogenized and then analyzed three weeks later using liquid chromotagraphy.

Mice moms, sons end up diabetic after short BPA exposure during pregnancy.

Mice moms, sons end up diabetic after short BPA exposure during pregnancy.

Jul 01, 2010

Alonso-Magdalena, P, E Vieira, S Soriano, L Menes, D Burks, I Quesada and A Nadal. Bisphenol-A exposure during pregnancy disrupts glucose homeostasis in mothers and adult male offspring. Environmental Health Perspectives http://dx.doi.org/10.1289/ehp.1001993.


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2010-0630bloodsugarmeter
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Brief exposure to low levels of bisphenol A during pregnancy may contribute to diabetic symptoms in the mother and her sons – but not daughters – finds a study with mice. BPA, which acts like estrogen and can interfere with normal hormone activity, caused changes in the mothers that resembled gestational diabetes. The mothers gained weight and could not properly regulate insulin, sugars and fats, even four months after the pregnancy. Their male pups showed similar deficits in metabolism, even though they had only been indirectly exposed for a brief period as fetuses.

Context

Intricate body systems process and store energy from food. When needed, sugars and fats are released. These mechanisms are delicately balanced. When they go awry, metabolic problems such as diabetes and obesity can occur. At no time are these systems more vulnerable than during pregnancy, when the energetic demands of the fetus compete with the mother’s regulation of her own body (Haig 1993).

Normally, insulin release causes sugars to be stored in cells for later use. During pregnancy, the body becomes increasingly resistant to insulin. This ensures that enough sugar remains in circulation to feed the growing fetus. Typically, the mother compensates by secreting more insulin so that blood sugar levels are kept in check.

These check and balance systems are easily derailed. When the mother’s body fails to adjust its insulin release, gestational diabetes – which afflicts up to 10 percent of pregnant women – may occur. Most cases of gestational diabetes resolve soon after birth, but many serious consequences may remain for both the mother and child. The children are often dangerously large at birth, and both mothers and offspring may find themselves at increased risk of obesity and Type II diabetes.

Because estrogen may play an important role in regulating the normal changes in metabolism during pregnancy (Nadal et al. 2009), anything that disrupts the body’s normal estrogenic activity may also throw the blood sugar regulation systems into upheaval, causing metabolic symptoms, and possibly contributing to diabetes or obesity.

The environmental chemical bisphenol A (BPA) – found in products throughout the modern world – is a compound that mimics natural estrogens. Concern first surfaced because it can leach from widely-used polycarbonate plastics, which were used a food packaging and water bottles. Recently, several reports brought attention to its overwhelming prevalence in canned goods (Consumer Reports 2009National Workgroup for Safe Markets 2010).

From food to household electronics to sales receipts, BPA is so commonly used in consumer goods that 95 percent of Americans have measureable levels in their blood. During pregnancy, BPA can pass from mother to the developing fetus.

Alarm bells were first raised about the chemical’s safety when animal studies showed that BPA could affect development of the reproductive system and the brain. More recently, concern has turned to whether BPA exposure may also impact metabolism. Several recent studies have linked BPA to diabetes, obesity and other symptoms of impaired metabolism in humans (Lang et al. 2008) and animal models (Alonso-Magdalena et al. 2006).

What did they do?

The researchers examined whether there were long-term metabolic effects on the mother and her pups exposed to BPA for a week during pregnancy.

Researchers injected pregnant mice with BPA from days 9 to 16 of pregnancy, which roughly corresponds to the development stage of middle to late pregnancy in humans. Some of the injected mice received a low dose of 10 micrograms per kilogram (μg/kg) of BPA each day while others received a high-dose of 100 μg/kg each day. Currently, the U.S. Environmental Protection Agency (EPA) and the Food and Drug Administration (FDA) consider anything below 50 μg/kg per day to be a low, and thus, “safe” dose.

The researchers measured glucose in the blood to determine if the pregnant mice processed sugars and responded to insulin – a hormone that helps the body store sugars after a meal. After birth, they continued to monitor the mothers and their offspring for their ability to metabolize sugar and insulin. They also examined how well the animals processed fats and how well their pancreases worked. The researchers compared these measures from BPA-treated mice to untreated mice and determined the physiological differences between the two groups.

What did they find?

Pregnancy typically entails some degree of insulin resistance, and this effect was amplified in the BPA-exposed mice, particularly in those receiving the lower dose of BPA. When compared to the untreated pregnant mice, their cells were less able to efficiently process and store sugars and their liver and muscle tissues showed a reduced insulin response similar to that seen in diabetic conditions.

Four months after giving birth, the BPA-treated mothers were heavier than the controls, even though their diets were the same. The mice in the high-dose group – but not the low-dose groups – had clear deficits in their cells’ ability to use insulin to store sugars. In both BPA-treated groups, levels of triglycerides – a type of lipid or fat – in the blood were elevated.

The mouse pups born to BPA-treated mothers also showed differences from control mouse pups. The low-dose pups were heavier at birth than controls – as is frequently the case with babies born to mothers with gestational diabetes. Yet, the high-dose pups actually weighed less than the controls.

As they aged, the BPA groups showed similar metabolic problems to their mothers. Although no significant differences were seen at three months of age, by six months, male – but not female – offspring in both BPA groups showed clear abnormalities in their ability to use insulin to store sugars. This deficit was consistently apparent in the blood tests and when the pancreatic cells were examined.

What does it mean?

Exposure to low levels of BPA at a crtical time in pregnancy may influence metabolic function during and after pregnancy, setting the stage for long-term gestational diabetes in the mothers and development of diabetes in sons as they age.

This study adds to a growing body of research evidence that, when taken together, suggests BPA causes health problems in animals and quite possibly in humans. Much of the research has focused on reproductive and developmental risks.

This study is one of a number of recent ones investigating whether BPA might have effects on metabolic conditions such as diabetes and obesity. But, it is the first to examine the mother’s risk of developing diabetes during pregnancy. While the recent studies have found some conflicting results, this new study’s methodological strengths mke the findings of particular concern.

Earlier this year, another group of researchers reported that prenatal and early postnatal BPA exposure in mice did not appear to lead to problems with blood sugar regulation, although they did find faster rates of growth during early development (Ryan et al. 2010).The new study improves upon earlier work, however, in that it is particularly comprehensive in its methods and approaches problems of insulin resistance and blood sugar regulation using a number of different methods. From sugar metabolism tests to measures of gene expression to blood chemistry, the multiple lines of evidence in this study all point to BPA having profound negative effects on the body’s ability to properly control blood sugar.

Beyond its methodological strengths, this new study adds two important nuances to our understanding of how BPA may impact metabolism. First, the study showed that even if BPA exposure occurs during a very brief period, the disruption in blood sugar regulation can be long-lasting. The female mice received BPA for only a seven day window during pregnancy, and yet were affected even months later, with higher weights and abnormal blood sugar and lipid levels.

In humans, of course, we are exposed continuously throughout our lifetimes as we ingest BPA in our food and pick it up through plastics and other sources every day. How this constant exposure might affect our bodies’ abilities to regulate blood sugars and other body systems remains an open ended question. However, these early results in mice are enough to merit additional research.

Second, the new study shows intergenerational effects. Males who were exposed to BPA as fetuses through their mothers displayed long-term metabolic problems resembling diabetes, even though they were never exposed to the chemical after birth. Because the body’s systems develop very early in life – often before birth – early exposures can cause permanent changes in body functions. In this case, through the ability to act as a pseudo-estrogen, BPA seems to permanently “program” body responses to sugar, causing an inability in the mice process the sugar – a condition that may mirror some of the most troubling current human health problems.

Aspects of the findings are also puzzling. Surprisingly, only male offspring were affected in this way by BPA exposure. The researchers hypothesize that perhaps the female offspring’s own estrogen production protected against the dysregulation, but further investigation would be needed to address that question.

In addition, low and high-dose BPA exposures didn’t yield the same findings. While both levels of exposure clearly produced negative health effects, it remains uncertain why the mice might respond differently to the two doses. The lower dose more closely approximates average human exposure levels. Ideally, future experiments will need to simulate the typical method of human exposure – ingestion through food – rather than injection.

Still, many questions remain unanswered, and more research is needed to fully understand how BPA impacts regulatory systems.

Resources

Alonso-Magdalena, P, S Morimoto, C Ripoll, E Fuentes and A Nadal. 2006. The estrogenic effect of bisphenol A disrupts pancreatic beta-cell function in vivo and induces insulin resistance. Environmental Health Perspectives 114(1):106-12.

Calafat, AM, Z Kuklenyik, JA Reidy, SP Caudill, J Ekong and LL Needham. 2005. Urinary concentrations of Bisphenol A and 4-Nonylphenol in a human reference population. Environmental Health Perspectives 113:391-5.

Concern over canned foods. 2009. Consumer Reports, December.

Haig, D. 1993. Genetic conflicts in human pregnancy. Quarterly Review of Biology 68(4):495-532.

Lang, IA, TS Galloway, A Scarlett, WE Henley, M Depledge, RB Wallace and D Melzer. 2008. Association of urinary bisphenol A concentration with medical disorders and laboratory abnormalities in adults. Journal of the American Medical Association 300(11):1303-10.

Nadal, A, P Alonso-Magdalena, S Soriano, AP Ropero and I Quesada. 2009. The role of oestrogens in the adaptation of islets to insulin resistance. Journal of Physiology 587(Pt 21):5031-7.

National Workgroup for Markets. 2010. Silver lining: An investigation into bisphenol A in canned foods (PDF).

Ryan, KK, AM Haller, JE Sorrell, SC  Woods, RJ Jandacek and RJ Seeley. 2010. Perinatal exposure to Bisphenol-A and the development of the metabolic syndrome in CD-1 mice. Endocrinology 151(6):2603-12.

Chemicals with unknown toxicity form when polypropylene plastic is heated.

Chemicals with unknown toxicity form when polypropylene plastic is heated.

Jun 25, 2010

Reingruber, E, M Himmelsbach, C Sauer and W Buchberger. 2010. Identification of degradation products of antioxidants in polyolefins by liquid chromatography combined with atmospheric pressure photoionisation mass spectrometry. Polymer Degradation and Stability 95:740-745.

Synopsis by Evan Beach
New chemicals – with unknown toxic properties – are present after heating commercial polypropylene plastics during manufacturing.

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The chemical composition of an everyday plastic could be more complicated than what a list of raw ingredients would suggest, report a group of Austrian chemists.

Their discovery concerns chemicals that manufacturers add to stabilize polypropylene (PP) plastics. The synthetic antioxidant additives break down when exposed to high temperatures typical of the manufacturing process, especially when they are combined with a common mineral filler called talc.

The results of this study add to the body of knowledge about chemicals found in everyday plastics. The findings could be used to more thoroughly assess the implications for environmental and human health.

Antioxidants are added to protect the structure of the plastic.  They are designed to react quickly with oxygen, sacrificing themselves to protect the PP chemical chain.

The discovery of the new chemicals is of concern since they may occur in commercial products where they could migrate out of the plastic and potentially into humans.  Talc-filled PP plastic is typically found in car parts, household appliances, and building materials.

The researchers did not measure the toxicity of the newly discovered chemicals, but their molecular similarity to the controversial product additives BHT and BHA suggests that they merit further study. While still widely used, the synthetic chemicals BHT and BHA have known health effects. They are used as antioxidants in many products, including food, cosmetics, pharmaceuticals, plastics and some petroleum-based greases and lubricants. BHT has been shown to cause mutations, tumors and endocrine effects in test animals. It has been responsible for allergic responses in people. BHA can also mimic the female hormone estrogen.

The researchers tested six commercial antioxidant additives, four of which had structures similar to BHT. In the presence of heat and talc, the additives lost parts of their chemical structures in predictable ways. This predictability means that chemists might be able to anticipate what will happen when new additives are exposed to heat and design for safer breakdown processes.

The chemists showed that although most of the pure additives were stable at 239 degrees Fahrenheit, all of them broke down when talc was present. Some also broke down when blended with the PP.  PP generally melts above 266 F. If the additives were blended into melted plastic, the high temperature would lead to their degradation, and thus, the new low-molecular-weight chemicals.

The observed decrease in molecular weight could lead to faster migration out of the plastic.  This question and the issue of toxicity could be resolved by further study.

© EnvironmentalHealthNews 2003-2004

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7 November Plastics, by the numbers, they’re everywhere. The bottom line: since plastics are a fact of life, learn how to pick and choose your plastics if you want to protect your health. Santa Cruz Sentinel, California.

4 September How to be poison-free going back to school. Parents, it is time to start stocking up on the latest school supplies, and many children’s supplies, such as lunchboxes, backpacks and binders, are often made out of PVC (#3 plastic). Collingwood Enterprise Bulletin, Ontario.

31 August Chemicals leach from packaging. Open a cereal box or a carton of juice, breathe in an asthma drug from an inhaler, or pop a pill out of a plastic pouch’s metal foil. Even when the wrapping comes off, you inevitably ingest some of the container. It is not a question of whether packaging components will leach into a product, it’s a question of how much. Chemical & Engineering News.

30 July ‘BPA-free’ bottles leach chemical: study. Health Canada scientists have found bisphenol A leaching into liquid in plastic baby bottles marketed to parents as being free of the toxic chemical. Canwest News Service.

22 June Battle of the bottles. Scientists are debating whether bisphenol A in plastic can actually harm humans, but when it comes to their babies some Irish parents don’t want to take any chances. Ireland’s Food Safety believes there is no need for parents to be alarmed about products containing BPA. Dublin Irish Independent, Ireland.

7 November Researchers raise alarm after chemical leak found in common plastic. Medical researchers at the University of Alberta say that two chemicals leaking from plastic laboratory equipment were so biologically active they ruined a drug experiment. Toronto Globe and Mail, Ontario.

23 April Conflicting reports target key chemical ingredient. For many consumers, the recent flurry of news reports about plastics and health hazards has been conflicting and confusing. San Diego Union-Tribune, California.

18 April Beverage bottlers waiting for word on bisphenol A. Although growing numbers of Canadian retailers are pulling plastic water bottles and baby bottles that contain the chemical BPA from their shelves, the beverage industry is generally in a holding pattern until Health Canada officially deems the chemical unsafe. Vancouver Sun, British Columbia.

13 March How safe are your bottles ? The decision to use hard plastic water bottles just got more complicated. Louisville Courier-Journal, Kentucky.

8 February Baby bottles linked to health risk. Most plastic baby bottles sold in the United States could be hazardous to a baby’s health, according to a new report by a coalition of environmental groups. Bergen County Record, New Jersey.

11 November Artificial turf full of toxins that can cause cancer. Every new expanse of artificial turf contains plastic grass and about 120 tons of finely chopped tires that emit a small amount of toxic, cancer-causing, mutation-triggering chemicals and metals. New Haven Register, Connecticut.

11 November Got plastic panic? There are solutions. Plastic is durable, flexible, inexpensive and virtually unbreakable. By those measures, it’s a consumer’s dream – and yet it just might be harming us. Canwest News Service.

2 November Several plastic bottles found unsafe to reuse. Studies have indicated that food and drinks stored in plastic bottles can contain trace amount of Bisphenol A (BPA), a synthetic chemical that interferes with the body’s natural hormonal messaging system. Phoenix Arizona Republic, Arizona.

New Report from Environment and Human Health, Inc: “LEED Certification Where Energy Efficiency Collides with Human Health”

LEED Certification Where Energy Efficiency Collides with Human Health, An EHHI Report

Breast Cancer, What Science Knows, What Women Think

Report Summary

Link to the Full Report

LEED Standards Are Being Adopted into Many Laws

Green Building Council standards are being incorporated into federal, state and local laws through legislation, executive orders, resolutions, policies, loan-granting criteria and tax credits. As demonstrated in this report, LEED standards are clearly insufficient to protect human health, yet they are being adopted by many levels of government as law. Thus the Green Building Council, a trade association for the building industry, is effectively structuring the regulations. The number of jurisdictions adopting these standards as law is growing, which will make them difficult if not impossible to change, unless federal law and regulation supersede the “green” standards with health-protective regulations.

No Federal Definition or Regulation of Green Building Standards

There is no federal definition of “green building standards” analogous to federal “organic food standards” or drinking water standards. Given regulatory neglect, many trade organizations have worked to create their own certification programs, hoping to capture growing demand for environmentally friendly and heath-protective buildings.

Energy Efficiency Given Priority Over Health

The LEED credit system is heavily weighted to encourage energy-efficient building performance. Nearly four times as many credits are awarded as energy conservation technologies and designs (35 possible credits) as for protection of indoor environmental quality from hazardous chemicals (8 possible credits).

Green Building Council Board Has Little Expertise in Environmental Health

Directors of the LEED Program are predominantly engineers, architects, developers, real estate executives, chemical industry officials and building product manufacturers. One medical doctor representing Physicians for Social Responsibility was recently appointed to sit on the board, which has 25 directors.

False Impression of Healthy Buildings

The Green Building Council’s award of “platinum,” “gold”, and “silver” status conveys the false impression of a healthy and safe building environment, even when well-recognized hazardous chemicals exist in building products.

Time Spent Indoors

Americans today are spending more than 90 percent of their time indoors. The EPA spends the majority of its resources working to manage outdoor threats to environmental quality and human health.

Tighter Buildings Increase Human Exposure

Energy conservation efforts have made buildings tighter, often reducing air exchange between the indoors and outdoors. Since outdoor air is often cleaner than indoor air, the reduction of outdoor-indoor exchange tends to concentrate particles, gases and other chemicals that can lead to more intense human exposures than would be experienced in better-ventilated environments.

However, the LEED program has been effective in encouraging more efficient heating and ventilation techniques, such as solar panels, geothermal wells, window placement and building orientation.

Toxic Chemicals in Built Environments

Tens of thousands of different building materials and products are now sold in global markets. Many of these products contain chemicals recognized by the U.S. National Toxicology Program, the CDC, or the World Health Organization to be hazardous.

These products include pesticides, chemical components of plastics, flame retardants, metals, solvents, adhesives and stain-resistant applications.

Some are carcinogens, neurotoxins, hormone mimics, reproductive toxins, developmental toxins, or chemicals that either stimulate or suppress the immune system.

Chemicals in Buildings Are Often Found in Human Tissues

The CDC began testing human tissues to determine the presence of some chemical ingredients of building materials. Most individuals whose tissues were tested carried dozens of these chemicals in their hair, blood or urine. Children often carry higher concentrations than adults. Chemicals released by building materials to indoor environments may be inhaled, ingested or absorbed through the skin.

No Level of LEED Certification Assures Health Protection

It is possible for new construction to be certified at the “platinum” level with no credits awarded for air quality assurance in the category “indoor environmental quality.”

Link to the Full Report

Intelligent commentary on a ‘Green Chemistry’ standard.

Common Ground For Going Green

Effort to develop a chemical industry standard is driven by the need to share comparative data

Stephen K. Ritter

CHEMICAL and ENGINEERING NEWS
May 10, 2010
Volume 88, Number 19, pp. 38-41

Chemical companies large and small are eager to become greener. They want to be able to select greener starting materials and use cleaner chemical processes to make environmentally preferred products. But there are no authoritative marketplace criteria to identify green, greener, or greenest. And for those who think they are green, there’s uncertainty over the best way to communicate the supporting information.

The solution: Develop a comprehensive voluntary industry standard that enables everyone from raw material suppliers and manufacturers to retail consumers and policymakers to exchange common information in a standard format on the environmental performance of chemical products and processes.

Government agencies, nongovernmental organizations, some chemical companies, and large retailers such as Walmart and Carrefour have already set out to develop assessment tools and enhanced metrics to achieve that ideal. But so far, these efforts are specific for individual classes of chemicals or market segments such as home cleaning products (C&EN, Jan. 25, page 12). In addition, the efforts tend to focus more on the consumer and less on the business-to-business world, where most chemical companies operate.

“There is a hunger in the marketplace for reliable, consistent, compelling information on which to base greener, more sustainable choices,” says Neil C. Hawkins, Dow Chemical’s vice president of sustainability and environmental health and safety. “Chemical companies need a life-cycle view—greenhouse gases, water, energy, renewables, waste reduction, recyclability—that encompasses all parts of the supply chain,” he says. “A standard is needed that provides guidance on the different types of data required, who should be publishing the data, in what form, and in what quality, so that you end up with a robust decision-making apparatus that will allow businesses and consumers to make fair comparisons and better choices.”

To that end, the American Chemical Society’s Green Chemistry Institute (GCI) is spearheading an effort to create the Greener Chemical Products & Processes Standard. This standard will provide data to allow anyone to evaluate the relative environmental performance of chemical products and their manufacturing technologies.

Many green standards already exist and typically are highlighted by product ecolabels, notes GCI Director Robert Peoples. Those standards are usually issued by companies themselves, industry trade groups, or environment-focused nongovernmental organizations, he says. They tend to center on one or two attributes, such as volatile organic compound emissions or percent recycled content. In addition, the tools used to establish such standards focus on the final products but don’t include the manufacturing process.

“We are building a multiattribute, consensus-based standard with third-party verification that a company can certify against to say that it has a greener product or manufacturing process than a competing product or a technology that it aims to replace,” Peoples explains.

Nearly 60 participants, including stakeholders from chemical companies, academia, trade groups, federal and state agencies, and nongovernmental organizations, are providing a balance of opinions to help establish the standard, he adds.

The process is being administered by NSF International, a global expert in standards development. The end goal is to have the standard issued by the American National Standards Institute. A draft of the standard is nearly complete and is expected to be released for public comment over the summer. The plan is to have final approval by the end of the year.

Peoples notes that the effort to develop the standard is drawing inspiration from green chemistry initiatives already in place. A primary example is the Environmental Protection Agency’s Design for the Environment (DfE) program, which encourages collaborative efforts between companies and environmental groups to screen chemicals and promote use of safer materials.

EPA staff develop DfE protocols for conducting screens of alternative chemicals based on threshold values for human and aquatic toxicity, bioaccumulation, persistence, and other parameters. Products that contain ingredients posing the least concern among chemicals in their class earn DfE certification and the right to use the DfE logo on the product label.

This strategy, known as “informed substitution,” is based on selecting chemical products that are fully assessed, have low hazard, and provide life-cycle benefits, notes Lauren G. Heine, science director at the virtual environmental nonprofit organization Clean Production Action. The goal of informed substitution is to move away from using the most hazardous chemicals, she says. Inherent in this model is an allowance for continual improvement by obtaining more data and a better understanding of what is greener and more sustainable over time.

The subscription online database CleanGredients is one business-to-business tool that uses DfE criteria to identify surfactants and solvents—and coming soon fragrances and chelating agents—that have optimal performance and environmental characteristics for making cleaning products. CleanGredients was created through a partnership between EPA and the nonprofit GreenBlue Institute, in Charlottesville, Va., where Heine previously worked.

CleanGredients encourages cleaning-product formulators to use greener chemicals and gives specialty chemical makers an opportunity to showcase their greener, safer products. Formulator companies don’t manufacture chemicals but instead purchase ingredients from chemical companies and then use proprietary recipes to mix them.

Even with tools such as CleanGredients, cleaning-product formulators spend a considerable amount of effort trying to analyze the properties of ingredients they want to use, “and they are feeling pretty challenged when they don’t have the resources of a large company like a Walmart,” notes Anne P. Wallin, Dow Chemical’s director of sustainable chemistry, who is participating in the GCI-led greener chemical standard-setting process. “They aren’t necessarily chemists, and they likely don’t have a toxicologist on their team. If we can give them reliable information in the form of a standard, it will be a huge leap forward for sustainability.”

Taking the CleanGredients model one step further is the Green Screen for Safer Chemicals, one of the tools developed by Heine and her colleagues at Clean Production Action.

Green Screen is the first open-source method to rank chemicals according to a comparative hazard assessment, Heine says. The screening tool goes beyond cleaning-product ingredients to evaluate all types of chemicals, which are categorized into one of four quantitative benchmarks, from “avoid—chemical of high concern” to “prefer—safer chemical.”

The benchmarks include hazard criteria that a chemical, its metabolites, and predicted breakdown products must pass, with a focus on the use and end-of-life phases, she adds. It also fills in data gaps with structure-activity relationship modeling data and expert judgment calls. Green Screen doesn’t include process or energy use information, but it can be applied to chemicals at any stage of the supply chain.

“Comparative hazard assessment tools are becoming an important piece of the sustainability puzzle,” Heine says. “People approach greening their chemical inventories by first moving away from chemicals of concern, perhaps driven by regulation. Once you start moving away from a known problem, you are pushed to the next level, where you have to consider more critically what is safer.”

Stakeholders working to frame the new Greener Chemical Products & Processes Standard are being informed by the best elements of initiatives such as CleanGredients and the Green Screen along with federal regulations as they generate the standard, notes GCI’s manager, Jennifer L. Young, who is representing the institute in the standards process.

The standard’s first phase, which is currently under development, covers individual chemicals and the processes to make them, Young explains. But it’s leaving out certain life-cycle elements such as sourcing raw materials and tracking the downstream use of the chemicals in making manufactured goods, an omission that’s caused some controversy among stakeholders.

Some of the stakeholders believe the standard should start out covering a chemical’s complete life cycle to understand its full environmental impact, from raw material extraction such as mining and oil and natural gas production to the end of a manufactured product’s lifetime and its recycling. The decision to move forward without those elements is not being taken lightly, Young emphasizes. But the effort required of companies to immediately go out and gather the new data, which many of them have never tracked before, would delay getting the standard implemented, she notes.

Looking past the scope of the standard, the framework includes multiple parameters in three primary categories: chemical characteristics, chemical processing, and social responsibility, Young says. The chemical characteristics category covers physical properties, human health effects, and environmental impacts. The chemical processing category includes water usage, treatment, and recycling data; efficiency of materials use with a focus on waste prevention; process safety; and energy use, Young explains. The third category, social responsibility, takes a look at global corporate practices such as adhering to labor laws and complying with regulations, she says.

Within the chemical characteristics category, there are three classification tiers based on hazard level and the amount of information available on a chemical, Young adds. The first tier includes chemical characteristics that are well studied and for which there are data determined by validated methods. A pesticide, for example, might require chronic ecological toxicity data from a 14-day test on earthworms with the results reported in milligrams per liter.

“Comparative hazard assessment tools are becoming an important piece of the sustainability puzzle.”

The second tier includes chemical characteristics that don’t have a lot of information and still may have cause for concern. In some cases, the data might not be available because the testing hasn’t been done, or they may not be provided by the manufacturer.

Young says the standard has to provide a balance between providing transparent but useful comparative information without giving away proprietary information. But data that are withheld because they’re considered confidential will be treated as missing data, she notes, which could lower the value of the chemical in the standard’s hierarchy and possibly prevent the chemical from gaining certification.

The third tier includes chemical characteristics that are new, considered to be problematic, or have little or no data, Young notes. For example, no one knows yet if some types of nanomaterials could pose a problem or not, she says. The standard makes no provision for requiring disclosure of these characteristics.

Some stakeholders are eager for the standard to provide a rating index or points system for ranking chemicals, Young says. Such a system would identify the “greenest” chemical in a class of compounds and provide a reference point for a company to gauge its progress in improving the chemical’s profile over time. But the initial version of the standard will leave it up to users to make their own comparisons, she says.

In addition, some members of the stakeholder group are dismayed that the standard is reactionary, rather than proactive, when it comes to addressing endocrine disruption, which is currently a polarized issue in science. Endocrine disrupters typically are man-made chemicals in the environment. They mimic hormones and can disrupt the endocrine system, potentially leading to negative health effects. Although scientists understand that people are susceptible to the effects of endocrine disrupters, it’s still unclear to what degree and under which conditions, and EPA is just beginning a long-delayed screening program (C&EN, Oct. 26, 2009, page 7).

Validated tests and models to understand dose-response relationships in endocrine disruption are still being optimized. As a result, data on endocrine disrupters are not initially required for the standard, Young notes. However, if endocrine-disrupter characteristics are associated with a chemical, the expectation is that the manufacturer will report that information to the customer. In a qualitative way, knowing that a chemical has been fingered as a potential endocrine disrupter could help a user make a judgment, she adds.

Because the majority of truly green chemicals and chemical products haven’t yet been invented, these criticisms point to a concern that setting a standard now could dilute the science of green chemistry by creating a “good enough” threshold. The concerned scientists say that such a threshold might allow chemicals that meet minimum qualifications to be certified, making it seem acceptable for some intrinsically dangerous chemicals to continue to be used, particularly if the standard is used to guide regulatory decisions. Given that possibility, some members of the green chemistry community have suggested that the word “greener” be struck from the standard’s title.

“Standards-making is messy,” Dow’s Wallin says. “You are trying to get a broad group of stakeholders together with a diverse set of viewpoints to find some middle ground and build on it. The need and the potential for a standard are both tremendous, and it is definitely worth the effort. It will be very powerful if we can work through all these issues and create a standard that the whole group can get behind.”

The science of sustainability and green chemistry is rapidly evolving, GCI’s Peoples adds. He emphasizes that just because someone initially certifies a product or process against the standard, it doesn’t mean it’s 100% green. “We need to revise and improve the standard over time,” Peoples says. “That means tightening the requirements and recognizing innovation as new science and technology are developed.”

A natural question asked about green chemistry and developing screening tools and standards is whether or not they can make a difference in the chemical marketplace. It’s still early in the sustainability game, but Peoples points to SC Johnson‘s Greenlist as a harbinger of success for the new green standard.

SC Johnson is the maker of many familiar brands of home cleaning, storage, and pest-control products, including Pledge and Windex surface cleaners, Ziploc storage bags and containers, and Raid insecticides. In 2001, the company created Greenlist with EPA’s backing as a methodology to rate the ingredients that make up its products. For Greenlist, environment and human health data are included alongside performance criteria and cost in the company’s chemical formulary, an index of ingredients that scientists use when designing products. The materials are rated 0 for restricted use, 1 for acceptable, 2 for better, and 3 for best.

When the program started in 2001, 18% of listed materials were rated better or best. The most recent data reveal that this number has climbed to 47%. But more critically, the zero-rated restricted-use materials have dropped from 10% to 2% of the total.

At first, SC Johnson had to challenge its suppliers to create better rated chemicals, according to the study. Now, the shoe is on the other foot; companies are designing new chemicals based on Greenlist criteria and are pitching them to SC Johnson to add to the formulary.

After the greener chemical standard is approved, communicating the information behind the certification will move to the forefront, Peoples says. One outcome could be an ecolabel that can be used on packaging for products made with certified ingredients. Individual chemicals don’t lend themselves to having an ecolabel because they are bought and sold mostly in bulk, he adds. Thus product documentation akin to a food nutrition label or a graphical label that shows sustainability attributes could be appropriate. For the business-to-business marketplace, information sheets and online reports for certified chemicals might be a format for communicating the standard’s supporting information, Peoples says.

“The importance of the standard-setting process is that we and our families are all inhabitants of this planet,” Peoples observes. “We don’t want to have problems with the quality of the water we drink or the air we breathe. But at the same time, we need to compromise and be creative,” he says. “There are billions or trillions of dollars of capital sunk into the ground in the chemical enterprise. Even if we wanted to, we couldn’t wave a magic wand and suddenly replace it tomorrow with pure green chemistry. It will take time to increase the level of awareness about the standard and decades to transition. But we need to agree now on a path forward and start taking our first steps.”

More On This Story

Story on animal testing confuses plastics issues.

Story on animal testing confuses plastics issues.

Posted by Evan Beach at Apr 16, 2010 10:00 AM | Permalink

The Valley Vanguard draws attention to some interesting fronts in endocrine disruption, but confuses issues related to plastics and chemical additives.

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A March 22 article in the Valley Vanguard reports on a clash between the animal rights organization People for the Ethical Treatment of Animals (PETA) and researchers at Saginaw Valley State University (SVSU). The reporter’s description of the SVSU research program provides an excellent, succinct summary of the differences between studies that focus on animal death or reproduction and those that explore fetal development in a more detailed way.

The article does erroneously link dioxins and the phthalate plasticizer DINP to water bottles, though.

Most water bottles are made from polyethylene terephthalate (PET) plastic (recycling #1), which is highly unlikely to contain dioxins or dioxin precursor chemicals. Urban legends have spread the myth that extreme cold or heat can release dioxins from water bottles, but PET contains no chlorine, the essential ingredient required for formation of the environmental contaminants. Dioxin formation is linked to burning of chlorine-containing PVC plastic (recycling #3), which is used in many everyday products but rarely water bottles.

The effects of DINP are also discussed in the article. DINP is a phthalate plasticizer commonly used as an additive for PVC plastic, not PET, so it should not be found in an ordinary water bottle. The confusion may arise from the similarity in names: PET contains building blocks called terephthalates and DINP is an orthophthalate. But as far as harmful effects are concerned, the connection stops there. DINP, DEHP, and other orthophthalates are associated with the hormone-disrupting effects described in the story. Readers who wish to avoid DINP exposure should stay away from soft, flexible PVC products (e.g. vinyl shower curtains, floor tiles, and children’s toys).

The PETA versus SVSU conflict is given a balanced presentation. However, it could have been better and more interesting if the story had further explored the larger question about non-animal testing methods. To provide greater depth into the issue would have informed readers about why other methods couldn’t be used for this particular research. One way to do this would be to include the viewpoint of a third party who doesn’t have a stake in the dispute.

Thought-provoking story describes alternatives to bisphenol A.

Thought-provoking story describes alternatives to bisphenol A.

Posted by Evan Beach at Feb 27, 2010 09:30 AM | Environmental Health Sciences

A February 23rd article in the Washington Post provides a well researched overview of potential substitutes for bisphenol A (BPA) in food containers. It raises important issues about scientists’ state of knowledge about exposures to chemicals in packaging materials and the food supply.

BPA is widely used in food can linings, and exposures through canned food are thought to be related to the frequency with which BPA is detected in the urine of the US population.  This application of BPA has also proven to be one of the most difficult in terms of finding a substitute technology.  The Washington Post article provides an excellent summary of the properties needed for high performance steel can linings and industry efforts to replace BPA-containing materials.

One of the most striking parts of the story is the revelation that one food company that switched to BPA-free steel cans is still finding trace amounts of BPA in its products. The source of contamination remains unknown.  This adds to growing evidence that estrogenic chemicals are so widely used in manufacturing supply chains that it has become difficult to pinpoint how and where in the process they are able to migrate into food and drink. For example, a 2009 study found that bottled water showed estrogenic effects after it was stored in Tetra Pak liners.  It is still unclear whether this was a result of the packaging materials themselves or some other aspect of the manufacturing process.

These findings suggest that our problems will not be solved just by replacing BPA in food can linings.  As discussed in the Post article, BPA is used in thousands of consumer products, increasing the chances of cross-contamination.  What’s not mentioned, though, is that BPA is not the only estrogen mimic showing up in food.  The problem is more systematic, begging the question, will the potential alternatives discussed in the story be any safer?

It is very difficult for a chemist sketching new molecules in a notebook to predict whether those structures will lead to a toxic product or a safe product.  This has led to situations described by NIEHS director Linda Birnbaum as like “jumping from the fry pan into the fire” when it comes to substitutes, as she said in reference to alternative flame retardants.

A possible solution to this issue is greater cooperation between environmental health scientists and green chemists, who are seeking to better understand the connections between chemical properties and toxic endpoints.  Progress in this area would make it easier to recognize chemical hazards as a design flaw.

The Post article did a good job bringing up difficult issues regarding chemicals in the food supply, and provided a rare focus on the quest for replacements.  Other journalists could follow suit and begin asking more pointed questions that dig deeper into how chemicals can be made safer.

“Science versus theology: the bisphenol A debate continues” – Pumphandle blog entry by Sarah Vogel

View the original Pumphandle blog post here.

Science versus theology: the bisphenol A debate continues

March 2, 2010 in Environmental Health | by The Pump Handle

by Sarah Vogel

If you thought the scientific debate about bisphenol A was over or even quieting down, you haven’t been reading the latest issues of Toxicological Sciences. (What are you doing with your spare time?) Last month in an editorial piece published in the journal, Richard Sharpe queried: “Is It Time to End Concerns over the Estrogenic Effects of Bisphenol A?”  His answer was an unequivocal ‘yes’, based on the latest study from Ryan et al. (published in the same issue) that found no reproductive effects from bisphenol A exposure in rats.  The study, according to Sharpe, “throws cold water on this controversy.”

Not so fast.  On Wednesday, February 17, 2010, the journal published a second letter to the editors, “Flawed Experimental Design Reveals the Need for Guidelines Requiring Appropriate Positive Controls in Endocrine Disruption Research,” by Fred vom Saal and 23 other researchers.  In a position quite contrary to Sharpe’s, the letter pointed to an important design flaw in the study.

This latest iteration of the controversy is about a fundamental and persistent challenge in the research on bisphenol A and other endocrine disrupting chemicals—what is the appropriate study design.  Issues of animal selection, route of exposure, animal feed and housing, and appropriate use of positive controls all point to the complexity of studying extremely low levels of endocrine disruptors.

These are not trivial issues.  Proper study design is essential to conducting good science, and charges of inappropriate design have been used to discredit research findings of adverse effects of as well as no effects of bisphenol A at low-doses.

This most recent letter critical of the Ryan et al. paper points to a flaw in the selection of dosing levels for the positive control.  To understand the argument requires a basic understanding of a positive control.

Let’s start with a very different example recently shared with me.  Say you have an unknown substance in the garage that you think might be a fertilizer.  To test this hypothesis you take two dishes of seeds and treat one with water and the other with the unknown substance and see what happens.  When there is no growth in the seeds of either treatment, you could conclude that the substance isn’t a fertilizer.  But what if the seeds you had started with were already dead?  So, you decide that a better way to test the unknown substance is to take three dishes of seeds and treat one with water, one with the unknown substance and a third with Miracle-Gro. This way if the seeds grow with Miracle-Gro you know they’re alive and reactive to fertilizer.  And if the seeds grow with the unknown substance and the ones in the water don’t, you know it’s a fertilizer. In this example, Miracle-Gro is the positive control and water the negative control.

But what happens if it turns out that when testing your seeds, you find that you have to use 10 times the amount of Miracle-Gro that is recommended to make the seeds grow?  What if your unknown substance is a fertilizer, but over the years of sitting in your garage has become less potent?  Your seeds might grow if you were to use a ton of the substance but because you didn’t have that much you only tested a small amount.  So in your study you use water, a small concentration of your fertilizer and a ton of Miracle-Gro.  You find that only the seeds doused with Miracle-Gro response positively.  This could lead you to incorrectly conclude that the unknown substance is not a fertilizer.

How does this apply to the critique of the Ryan et al. paper?  In their study the researchers used a positive control, ethinylestradiol (EE), the hormone used in birth control.  However, they had to use extremely high doses to trigger the reproductive endpoints of interest (e.g. sexually dimorphic behavior, age at puberty, reproductive function).  They basically had to douse these rats with this estrogen to elicit a positive response—that is, to make the positive control work.  If they had used lower concentrations they would have observed no effects.  At the lowest concentration of EE used, 5 µg/mg, Ryan et al reported no effects in the animals.  The letter by vom Saal et al. noted that the pharmacologically effective dose of EE in oral contraceptives used in humans is less than 0.5 µg/mg.  So the rats used in Ryan et al.’s lab were not sensitive to levels of EE above the concentration used to avert pregnancy in women.

Given that it took such high concentrations of the positive control to elicit a positive effect, the researchers should have selected much high concentrations of BPA. This is because as demonstrated by the positive controls, the animals are insensitive to estrogen.

The details of this scientific debate can be confusing, particularly for the non-scientists.  But what it unsettling about Sharpe’s commentary is that he turned what should have been a scientific debate into a theological discussion.  Sharpe used the recent findings by Ryan et al. to paint a simplistic picture of the bisphenol A debate as a struggle between rational facts observed by scientists and exemplified in the Ryan et al. article, and “believers” of false hypotheses propagated by “nonscientific” media, blogs and website. According to Sharpe, these “believers” argue that bisphenol A has estrogenic effects at low doses, whereas scientists prove otherwise.

Simplifying a complex scientific debate using theological arguments ironically achieves the exact opposite intent of Sharpe’s editorial.  Rather than pulling this debate out of the mire, Sharpe drags it back in, and in the process, pulls it away from the rich scientific debate that needs to occur, particularly in the pages of scientific journals.

It is a credit to the 24 bisphenol A researchers that they did not take offense to this characterization of their work and careers.  They chose to stick to the scientific aspects of the debate and provide recommendations for appropriate use of positive controls.

In publishing the recent letter to the editor, Toxicological Sciences pushes scientific progress forward one small step by encouraging healthy and constructive skepticism and scientific debate.  Now we must wait for the next installment: a response from Ryan et al.

Sarah Vogel received her PhD from  Columbia University in the Department of Sociomedical Sciences’ Center for the History and Ethics of Public Health and Medicine; her dissertation was entitled “Politics of Plastic: the economic, political and scientific history of bisphenol A.” She holds master’s degrees in public health and environmental management from Yale University. She authored the case study “Battles Over Bisphenol A” at DefendingScience.org.