Creating Healthy Learning Environments
Identifying and removing toxic hazards from educational buildings
March 2015
Peter J. Arsenault, FAIA, NCARB, LEED AP
Continuing Education
Use the following learning objectives to focus your study while reading this month’s Continuing Education article.
Learning Objectives – After reading this article, you will be able to:
- Identify and recognize the current state of educational facilities and the issues related to healthy indoor environments.
- Investigate the human impacts of toxins found in common building products used in school and educational buildings.
- Assess the available tools available to help design professionals and others gain transparency into the make-up and toxicity of building products.
- Specify products for educational facilities that are healthier, more sustainable, and cost effective over the life cycle of the building.
Across the United States it has been documented that there are currently over 100,000 public and private K-12 schools plus over 5,000 colleges and universities that collectively define the education sector of our society and the built environment. These buildings and facilities are central forces in the lives of some 60 million K-12 students, 20 million college students, and 13-15 million faculty members and support staff. Altogether, that represents almost one-third of the U.S. population who spend a significant portion of their waking hours in an educational setting.
We take for granted that these facilities are safe, healthy, and productive environments in which children and adults can learn, grow, and develop. However, solid scientific evidence is increasingly linking the epidemic rise in serious health issues among our nation’s youth to exposure to conditions and toxins emitted by what have been considered “standard” school building construction materials, cleaning products, and maintenance practices. The alarming reality is that educational settings may in fact be a hotbed of hazards that are compromising the health of their occupants and children’s ability to learn.
The Current State of Schools
According to the National Center for Education Statistics, the typical American school was built in the 1950s to 1960s and is an average of 50 to 60 years old. They have determined that most have outdated building products and outmoded maintenance procedures. The United States Environmental Protection Agency (EPA) has recognized the potential for problems within an aging inventory of school buildings and conducted a study titled “Indoor Air Quality Tools for Schools: Actions to Improve Indoor Air Quality.” They found that up to half of our nation’s schools have problems associated with indoor air quality, most notably from the growth of mold and mildew created by damp indoor environments. In related work, other EPA studies confirm indoor levels of pollutants in buildings, including schools, may be over 1,000 times higher than outdoor levels.
Photo courtesy of Forbo Flooring Systems
Selecting building products for education facilities that do not contain harmful chemical compounds or require extensive cleaning, helps create healthier indoor learning environments.
Photo courtesy of Forbo Flooring Systems
The average school building in use today is not a new one, but an existing building that may be 50 to 60 years old with issues associated with materials and maintenance.
Where do those pollutants come from? Experts worldwide confirm that a variety of toxins known as volatile organic compounds, or VOCs, can be emitted from certain building construction materials, cleaning and maintenance products, or school supplies. VOCs include substances such as formaldehyde and glycol ethers as well as plasticized polyvinyl chloride (PVC). PVC is a thermoplastic made of 57 percent chlorine (derived from industrial grade salt) and 43 percent carbon (derived predominantly from oil/gas via ethylene) which is made softer and more flexible by the addition of chemicals known as phthalates. PVC and phthalates are often used in common products such as vinyl flooring, carpets, building materials, floor strippers/finishes, and in school supplies such as binders, backpacks, lunchboxes, and laptops. VOCs and phthalates contain known human toxins that are absorbed through the respiratory system or through skin contact, leading to potential health hazards for those exposed.
In addition, since (and despite) the enactment of the Toxic Substance Control Act of 1976, 84,000 chemicals remain untested for toxicity and are potentially harmful. The overwhelming majority of these chemicals don’t require testing and less than five have been regulated or banned under this law. Some are legal in the U.S. based on the quantity present in a given product and their ability to flow from that product to people, i.e. the exposure level. The presence of these hazards is further exacerbated by school buildings that are tightly sealed and/or poorly ventilated—a condition prevalent in both old as well as newly constructed facilities.
Photos courtesy of Forbo Flooring Systems
Chemicals found in building products and cleaners can contain toxic and potentially harmful characteristics.
When it comes to maintenance in schools, there is also a concern. In 2008 the 21st Century School Fund conducted a study, along with the separate American School & University’s 36th Annual Maintenance & Operations Cost Study for Schools that revealed that U.S. public schools spent only about $5 per square foot per year to maintain and operate a school. At that level, the average school reportedly spent less than half of the money on maintenance, repair, and capital renewals than would be necessary to bring it into a state of good repair and optimal environmental conditions for students. With only this amount to spend on building maintenance, it would seem wise for schools to invest in products that require minimal maintenance and post-installation expenses. However, growing financial pressures and a historic disconnect between capital and operating budgets, especially in the K-12 arena, have often driven less-than optimal investment decisions. Building materials are often selected to satisfy only first-cost, short-term budget issues without understanding the long-term cleaning and maintenance costs associated with cleaning supplies and operations labor.
Human Impacts of School Environments
With the presence of potentially harmful substances in school buildings, is there any impact on students, staff, or teachers? To answer that question, highly respected medical and scientific organizations worldwide have begun tracking the impact of exposure to some of the toxic chemicals we have described. These organizations include medical organizations such as the U.S. National Institutes of Health, Harvard School for Public Health/Harvard Medical School, and the Asthma Regional Council of New England (ARC). It has also included organizations specifically focused on buildings and the environment such as the Healthy Building Network, the U.S. Green Buildings Council (USGBC), and the Center for Health, Environment & Justice (CHEJ). Even state legislatures in California, New York, and elsewhere have initiated investigations into human impacts from material exposures. These efforts have revealed a number of findings concerning health concerns among children that have been documented to be on the rise.
First of all, some studies have found that children are especially vulnerable to chemical toxins emitted from materials and substances in buildings. In particular, children consume more food, liquid, and air for their size and body weight than adults, making them more susceptible to the absorption of chemicals that can potentially harm their still developing immune systems, brain functions, metabolisms, endocrine systems, etc. Based on their highly tactile and oral nature (e.g., sitting on, playing with, touching, or even tasting objects or surfaces containing toxic substances), children are at greater risk of breathing in or ingesting toxic chemicals emitted by suspect building materials, maintenance products, and school supplies. Compounding this vulnerability is the fact that children are spending more time in school buildings than ever before. At 35 to 40 hours per week for 9 to 10 months per year, along with an increasing amount of time spent in school settings for after-school activities, daycare, meals, and community events, children are spending the equivalent of two to three years of their formative lives in school buildings with the potential for toxic exposure.
Photo courtesy of Forbo Flooring Systems
Unless carefully selected and understood, building products used in educational settings may contain ingredients and chemical compounds that are known to be harmful to both the environment and to human health.
Connections to Chemical Compounds
Different studies have shown a link between certain chemical compounds and specific diseases or disorders. Some of these are summarized as follows: (References to studies can be found on page 5.)
Photo courtesy of Forbo Flooring Systems
In educational settings, building materials that contain harmful chemical compounds have been linked to numerous adverse health conditions in students, teachers, and staff.
Autism. A 2009 study found a statistically significant link between polyvinyl chloride (PVC) and phthalates found in building materials and school/office supplies and the incidence of autism spectrum disorders, concluding that children continuously exposed to these toxins may be twice as likely to have autism. Cases of autism spectrum disorders have been documented to increase by 78 percent since 2002 and currently affect 1 in 88 children, a number still on the rise.
Asthma. A Healthy Building Network study identified a dozen chemicals commonly used in building products, foam insulation, paints, adhesives, floors, and carpets that can lead to the development of asthma in children, especially the presence of phthalates, which can impair the development of the lungs and immune system. The prevalence of asthma among children nearly doubled between 1980 and 1995 and currently affects 7 million children, or 1 in every 13. Considered the #1 chronic childhood illness, asthma is a leading cause of school absenteeism, with some 14.7 million school days missed each year due to this condition.
Learning disabilities. A recent South Korean study found that children with higher concentrations of two common phthalates in their urine had lower IQ scores than their peers. The number of children classified with learning disabilities increased by 191 percent between 1977 and 1994. Currently, as many as 1 in every 6 children is believed to have a learning or developmental disability of some kind.
Attention deficit. Exposure to phthalates has been linked to the rise in attention deficit hyperactivity disorder (ADHD), which has increased six-fold between 1985 and 2000 and may affect as many as 1 in 6 children today.
Childhood cancers. Leukemia, brain cancer, and other childhood cancers have increased by more than 20 percent since 1975 and early puberty and other signs of endocrine-related disruption is now experienced by 1 in 10 girls, a condition which poses a risk factor for breast cancer later in life.
Obesity. Exposure to phthalates has also been linked to obesity, which currently affects 16 to 33 percent of U.S. children and teenagers.
Laurie Stillman of the Asthma Regional Council of New England has summed it up this way: “VOCs may contribute to any of a full range of health effects, including triggering an asthma attack in someone who already has asthma, gradually leading to the development of asthma in someone who doesn’t have it, or contributing to health effects ranging from minor irritation to cancer.” To add insult to injury, a recent study found childhood health issues caused by environmental hazards such as air pollution and exposure to toxic chemicals cost the U.S. $76.6 billion in 2008 and have been on the rise.
Connections to Mold and Mildew
As noted, the EPA has identified that up to half of our nation’s schools have problems associated with the growth of mold and mildew created by damp indoor environments. The Healthy Building Network, an organization dedicated to transforming the market for building materials to advance the best environmental, health, and social outcomes, confirms that the presence of mold and mildew caused by standing water or damp conditions in school environments increases the risk of chronic allergies and asthma among children. They note that this moisture can further accelerate the emission of hazardous chemicals into the air from building materials—all increasing the risk of serious health consequences for the children, teachers, staff, and community members who use these facilities.
Photo courtesy of Forbo Flooring Systems
Selecting products that do not promote mold or mildew and that have some antimicrobial characteristics helps to overcome health issues associated with asthma and the spread of infectious disease.
Connections to Infectious Bacteria
In recent years, there has been an awareness of the need to control the spread of infectious bacteria in many institutional settings, including schools. Staphylococcus aureus, often referred to as “staph,” are bacteria commonly found on the skin or in the nose of healthy people. Approximately 25 to 30 percent of the population are colonized with staph bacteria (i.e., carry the bacteria without becoming ill). Sometimes staph causes minor skin infections (e.g., pustules, small boils) that can be treated conservatively, without antibiotics. However, on occasion, staph bacteria can cause much more serious skin infections, as well as bloodstream infections, pneumonia, etc.
Methicillin-resistant Staphylococcus aureus (MRSA) is a type of staph that is resistant to some antibiotics, including the antibiotic methicillin. Infections caused by MRSA have historically been associated with ill persons in healthcare institutions. However, MRSA has now emerged as a common cause of skin and soft tissue infections that may occur in previously healthy adults and children who have not had prior contact with healthcare settings.
This type of MRSA infection is known as community-associated MRSA (CA-MRSA) and can be transmitted from person to person through close contact. Risk factors associated with the spread of MRSA include direct skin-to-skin contact with colonized or infected persons (non-intact skin serves as a point of entry for the bacteria), sharing contaminated personal items (e.g., towels, razors, soap, clothing), inadequate personal hygiene, direct contact with contaminated environmental surfaces, and living in crowded settings. CA-MRSA infections are treatable; early recognition and good medical management, including, as needed, surgical drainage and proper antibiotic prescribing and use, help to ensure prompt resolution of infections.
Recently, there has been an increase in the number of outbreaks of CA-MRSA skin and soft-tissue infections reported at the national level. Outbreaks of CA-MRSA have occurred among student athletes, especially participants in contact sports (e.g., football, wrestling) and sports where participants are prone to skin abrasions. The most important approach to preventing MRSA transmission is through simple measures such as good personal hygiene, and covering infections. However, the environment may play a role in some cases of MRSA transmission when surfaces are touched or used by multiple people. Routine surface cleaning, utilizing an EPA-registered disinfectant cleaner, of frequently touched surfaces and surfaces that come into direct contact with people’s skin, such as shared athletic equipment (e.g., wrestling mats and strength training equipment) can certainly help. In order to be effective, mats and other high-use athletic equipment should be cleaned before and after each practice and several times a day throughout a tournament.
Transparency: Determining Healthy Products
Given the extent and range of potential issues and impacts from school environments, how does a design professional know what to specify? There are industry standards such as the Resilient Floor Covering Institutes FloorScore IAQ and the Collaborative for High Performance Schools (CHPS) Section 01350. However, these measure a product’s VOC emissions as tested in a dark chamber with a controlled temperature of 75 degrees F (23 degrees C). But scientific studies have found that even a 10-degree C increase in temperature raises toxic VOC emissions from products such as PVC almost tenfold. That means that products that pass a standard in a laboratory may be failing in real world applications.
Realizing the limitations of a single test, there are some recently developed alternatives that a specifier can request and rely on in order to make informed choices on the materials being used in buildings. Three are summarized as follows:
Environmental Product Declaration (EPD)
An environmental product declaration (EPD) is a document created by a manufacturer to show the results of a life-cycle assessment (LCA) performed on its product(s) in accordance with ISO standards. Before being published, the EPD needs to be verified and approved by an independent entity such as UL Environment (ULE) or the Institute for Market Transformation to Sustainability (MTS). The fully vetted EPDs thus enable everyone involved to make accurate direct comparisons of the environmental strengths and weaknesses of similar products, thus providing a degree of transparency in terms of the environmental impacts of using different building products. Many in the green products industry regard the EPD to be a standardized tool used to communicate the environmental performance of a product. It works in the same way that a nutrition label on a food product informs us about the fat, sugar, and cholesterol in the foods we eat. However, while providing adequate disclosure of environmental impacts, an EPD does not address toxicity potentials or human impacts associated with the products.
EPDs play a notable role in LEED® version four which was released in 2013. The Materials and Resources (MR) section has substantial revisions compared to prior versions such that points previously available for regional materials and recycled content are being rolled into the points available for LCAs and EPDs. Happily, the USGBC is not asking project design teams to conduct LCAs or to become LCA experts. Instead, the project team will be able to request an EPD that discloses the required LCA-based information. In essence, LEED® version 4 asks product manufacturers to gather the life-cycle information on their products and to disclose relevant portions of that information in the standard EPD format.
Health Product Declaration (HPD)
Going beyond disclosure of life-cycle impacts of products, attention has been given to the toxicity of those products on the natural environment (ecotoxicity) and people (human toxicity). In response, a group of leading architects, building managers, and product manufacturers have banded together to create a whole new standard called the Health Product Declaration (HPD), which represents a major step forward in product transparency. HPDs build on and incorporate the data from the EPD but go on to combine it with trustworthy and verifiable measures of ingredients that impact ecotoxicity and human toxicity. As such, it creates a disclosure document that truthfully indicates the toxicity impact of a product on the people who live with it, and the natural environment that it exists within. As envisioned, the HPD will create a single standard that can be used to create an apples-to-apples comparison of products based on their ingredients.
The true beauty of the HPD is its ability to be impartial, while also addressing industry concerns about the fairness of standards. To remain objective, HPDs use an open-source approach to decide which criteria are included, placing decision-making power in the hands of architects, specifiers, and others without a vested interest in the outcome. On the one hand, radical environmentalists cannot unduly sway the standard but neither can industry insiders with a status quo to protect. All professionals can have input in shaping the standard to keep it practical and fair. Admittedly, it is difficult to measure the absolute potential for future toxicity without a crystal ball. But if judgments must be made, it is a far better idea to have everyone in the product safety equation at the table sharing all the information available. It is far better for human health and our natural environment as well.
Image courtesy of Forbo Flooring Systems
The USEtox program identifies a more complete view of the toxicity of a building product and displays it in simple, familiar ways.
The USEtox Model
USEtox is a scientific consensus model for characterizing human and eco-toxicological impacts of chemicals in a life-cycle impact assessment. It is a Life-Cycle Initiative jointly created by the United Nations Environment Program (UNEP) and The Society of Environmental Toxicology and Chemistry (SETAC). UNEP participates through its Sustainable Consumption and Production Branch (SCP) which promotes resource efficiency by encouraging sustainable consumption and production patterns. Its activities aim to reduce environmental impacts and help meet human needs by producing more with less. SETAC is a not-for-profit, global professional organization comprised of some 6,000 individual members and institutions from academia, business, and government. Since 1979, the Society has provided a forum where scientists, managers, and other professionals exchange information and ideas on the study, analysis and solution of environmental problems, the management and regulation of natural resources, research and development, and environmental education. The USEtox model has been developed by the USEtox Team, a team of international researchers from the Task Force on Toxic Impacts under the auspices of UNEP/SETAC Life Cycle Initiative.
The premise of the USEtox program is similar to an HPD but with a different output on a product including a database of factors such as environmental fate, exposure, and effect parameters for human toxicity and ecotoxicity. Essentially, it allows a label to be developed that is similar to a nutrition label for food. Instead of listing things like vitamins, fat, and fiber information however, it lists summary ecotoxicity information, human toxicity information (cancer and non-cancer), and complete ingredients all of which can be built from EPDs and HPDs. Most of us prefer to buy food knowing what is in the product and how it affects our health—the USEtox program strives to provide the same information for building products.
Designing Healthier Outcomes
In order to illustrate how all of this very good work and information all come together in a real building, we will use flooring as an example by comparing common vinyl flooring with alternatives.
Vinyl Flooring Concerns
Vinyl flooring is made from PVC with associated phthalates as are the adhesives used in its installation and many of the supplies used to clean it. PVC and phthalates have been shown to be considered among the most toxic chemicals in school settings. Further, while it’s believed that the “normal” emission of VOCs from vinyl flooring products under standard use and maintenance can pose significant health risks to occupants, recent studies show that the presence of excessive water or heat can further accelerate those emissions and expose occupants to even greater levels of toxicity. For example, the use of lower-quality adhesives and/or outdated application practices can create airspaces and ridges that promote the collection of dirt and water and subsequently foster the growth of dangerous mold and mildew under the surface. In addition, water pooling under impermeable surfaces such as vinyl flooring can potentially pop the flooring, leading to emission of PVC from sub-floor adhesives.
Alternative Flooring Choices
In order to avoid the issues described that are associated with PVC flooring, we can choose flooring and adhesive products that are made from other materials to create healthier learning environments. Specifically, we can look for flooring products that can demonstrate the elimination or a reduction in the use of chemical compounds of concern such as PVC and phthalates. We can also seek flooring systems that produce a reduction in the likelihood of mold and mildew forming, and offer antimicrobial properties that promote infection reduction. The flooring products that meet these preferred criteria are those that use natural materials that have been found to be naturally antimicrobial, mold and mildew resistant, toxin- and biocide-free. A popular and readily available alternative to vinyl that fits this product profile is found in linoleum-based products. Commonly made from 100 percent bio-based and biodegradable ingredients, contemporary linoleum products display health and sustainability advantages for schools. It is also ideal for other school applications including furniture surfaces, walls, and bulletin boards.
In a recent independent test of a natural linoleum-based flooring and adhesive versus another resilient flooring product used with a traditional dry-set adhesive, the linoleum system achieved 100 percent contact between the back of the tile and substrate, creating a water-resistant layer that fully sealed all areas of the backing and filled all cracks and joints. When both tiles were exposed to water, as under a water fountain, the dry-set adhesive used with vinyl tile achieved only 50 percent adhesive contact, producing channels and tunnels that allowed water to travel and pool under the flooring, creating opportunities for the growth of mold and mildew.
Photo courtesy of Forbo Flooring Systems
Selecting materials such as linoleum instead of vinyl flooring helps reduce the presence of PVC and phthalates in school environments, thus reducing the associated health risks.
According to the Asthma Regional Council of New England, among the most critical decisions for schools is the choice of flooring materials that utilize “low-VOC products and flooring surfaces less likely to exacerbate moisture/mold and allergen issues.” By choosing the right flooring product, a quality adhesive that doesn’t allow moisture to accumulate under the flooring, and a proper maintenance regime, schools can enjoy safer, healthier, and longer-lasting flooring. Further it avoids the need for toxic finishes and harsh chemical cleaners that are associated with vinyl flooring maintenance. Hence, the cleaning and maintenance of linoleum flooring is healthier and simpler than with vinyl flooring since no toxic, time-consuming, or costly repeated finish and maintenance work is required.
Photo courtesy of Forbo Flooring Systems
Natural, bio-based products can be used on all surfaces of educational environments to help create healthy learning environments.
Cost Comparison
Though vinyl flooring appears to deliver a lower first-cost than other flooring options, the occupancy-ready and total life-cycle cost of vinyl is in fact much higher than others. Healthier, more sustainable alternatives have been found to be more cost-effective to install and maintain. This is due to the expense of the products prescribed to clean, seal, and maintain vinyl flooring from its initial installation through its life, which, ironically, is significantly shorter than other options.
An economic analysis conducted by the University of Florida found that vinyl flooring carries the highest lifetime cost compared to a range of other popular alternatives. Natural, bio-based products are available with a fully guaranteed and occupancy-ready product and installation price on the order of $3.55 per square foot that is more cost-effective to install and maintain over the entire life cycle than other solutions. Further, savings on the order of $1.00 per square foot are possible through the use of lower-maintenance and more environmentally friendly, healthy flooring options. This means 20 percent of the average annual maintenance budget ($5.00 per square foot referenced earlier) could ultimately be redirected to support other critical needs in the care and maintenance of buildings including replacing other materials of concern.
Conclusion
When designing and specifying products and materials to be used in schools, selections can be made based on finding the healthiest choices for students, teachers, and staff. There are an increasing number of data and tools that allow design professionals to investigate and measure the health of an educational environment particularly as it relates to products and ingredients. It is important that we request manufacturers to continue taking steps toward full transparency (and product improvement) by asking for EPDs, HPDs, and USEtox data. In this manner we can confidently replace harmful products with sustainable alternatives. And in the interest of presenting building owners with the best value for their budgets, it is incumbent on us to consider not only initial installation costs, but the cost to maintain the products over its lifetime.
Peter J. Arsenault, FAIA, NCARB, LEED AP, is an architect and green building consultant who has authored over 100 continuing education and technical publications as part of a nationwide practice. www.linkedin.com/in/pjaarch
References
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http://www.chicagotribune.com/news/chi-0207210272jul21,0,2177158.story
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6. “Toxic Chemicals in Building Materials; An Overview for Health Care Organizations” Kaiser Permanent and the Healthy Building Network /Healthcare Without Harm, May, 2008
7. Pharos Product Category Descriptions – Resilient Flooring http://www.pharosproject.net/product_category/show/id/3
8. America’s Children and the Environment, U.S. Environmental Protection Agency, 2008. http://www.saferchemicals.org/resources/health.html
9. Holly L. Howe, et al., “Annual Report to the Nation on the Status of Cancer (1973 through 1998), Featuring Cancers with Recent Increasing Trends,” Journal of the National Cancer Institute, 93, no. 11 (June 2001): 824–42. http://www.saferchemicals.org/resources/health.html
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15. Kate Brett, “Fecundity in 2002 National Survey of Family Growth Women 15–24 Years of Age” (personal communication), Hyattsville, MD, National Center for Health Statistics (2008) http://www.womensvoices.org/issues/reports/the-health-case-executive-summary/
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17. National Institute of Mental Health, “NIMH’s Response to New Autism Prevalence Estimate,” http://www.nimh.nih.gov/about/updates/2009/nimhs-response-to-new-autism-prevalence-estimate.shtml
18. Scientific American “The Baffling Link Between Autism and Vinyl Flooring,” Marla Cone, Environmental Health News 2009
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