Research & Reports
Reclaimed Asphalt Pavement (RAP) in Building & Construction Asphalt (also known as asphalt concrete, bitumen, or road tar) is the most common paving material by far, accounting for a 92 percent share of the 2.5 million miles of roads and highways in the United States. Reclaiming and reusing asphalt has many benefits, including waste prevention, reduction of greenhouse gas emissions, and lower lifecycle impacts compared to virgin asphalt material use. Keys to increasing the recycling of asphalt and its attendant environmental benefits include simplifying the designs of asphalt mixes, reducing toxic additives in production, tracking materials from production through use and recycling, testing incoming materials for contaminants, and avoiding the addition of cutback solvents and other toxic rejuvenating agents.
TSCA Workplan Chemicals Reports On March 15, 2017, the Healthy Building Network, the Environmental Health Strategy Center, and Safer Chemicals, Healthy Families, submitted detailed comments to EPA on five chemicals to be evaluated under the recently strengthened federal chemical safety law, the Toxic Substances Control Act (TSCA). The groups provided new information on these chemicals’ production, import, use, and disposal. Some of this information, which is based on a review of shipping records on the international trade in toxic chemicals, has never before been made available to the public. EHSC and SCHF also submitted comments on a sixth chemical, methylene chloride.
Healthy Environments: Understanding Antimicrobial Ingredients In Building Materials Building products incorporating antimicrobial additives are becoming increasingly prevalent. Paints, and other touchable surfaces such as countertops, and virtually any product considered as an interior finish may contain one or a combination of antimicrobials. These agents are considered pesticides, but their identity—and related hazards—can be difficult for the average person to discover. This lack of transparency creates a hurdle for the informed selection of products with reduced negative impacts.
No evidence yet exists to demonstrate that products intended for use in interior spaces that incorporate antimicrobial additives actually result in healthier populations. Further, antimicrobials may have negative impacts on both people and the environment. This paper, prepared by Perkins+Will in partnership with HBN, aims to present current information about reported or potential health and environmental impacts of antimicrobial substances as commonly used within the building industry, and to assist architects, designers, building owners, tenants, and contractors in understanding those impacts.
Post-Consumer Polyethylene in Building Products Polyethylene is the world’s most common plastic. It is used in packaging, food and beverage containers, and consumer products. Building product manufacturers sometimes use post-consumer recycled polyethylene bags and bottles in pipes and plastic lumber. This scrap usually has minimal contents of concern, but products like detergents stored in plastic packaging can remain. So-called “bio-degradation” agents in plastic bags also contaminate this feedstock and should never be used. The plastics recycling industry is developing protocols to screen out residual contaminants. Of greatest concern: Most polyethylene goes unrecycled in the United States due to problems in supply chain controls and the low price of virgin resins. This report examines ways to optimize the use of post-consumer polyethylene in building materials.
Post-Consumer Flexible Polyurethane Foam Scrap Used In Building Products Healthy Building Network’s research into current recycling practices for flexible polyurethane foam (FPF) indicates that most post-consumer feedstocks are contaminated with highly toxic flame retardants. Discussions of recycling FPF have centered around the human health and environmental hazards posed by the flame retardant PentaBDE, which the foam industry phased out a decade ago. But the flame retardants that have replaced PentaBDE present similar concerns. Manufacturers incorporate flame retardant-laden post-consumer FPF into new products, primarily bonded carpet cushion. Recycling and installation workers and building occupants, particularly crawling children, can be exposed to these toxic chemicals. The recent emergence of pre-consumer FPF scrap that is free of flame retardants is a great step toward a safer, more valuable feedstock, but more work is needed to track and label flame retardant-free FPF to ensure that future post-consumer foam is also flame retardant-free.
Healthy Environments: What's New (and What's Not) With PVC This paper was prepared by Perkins+Will, in partnership with Healthy Building Network (HBN), as part of a larger effort to promote health in the built environment. Indoor environments commonly have higher levels of pollutants, and architects and designers may frequently have the opportunity to help reduce or mitigate exposures.
The purpose of this report is to present information on the environmental and health hazards of PVC, with an emphasis on information found in government sources. This report is not intended to be a comprehensive analysis of all aspects of the PVC lifecycle, or a comprehensive comparative analysis of polymer lifecycles. Rather, in light of recent claims that PVC formulas have been improved by reducing certain toxic additives, this paper reviews contemporary research and data to determine if hazards are still associated with the lifecycle of PVC. This research has been surveyed from a perspective consistent with the precautionary principle, which, as applied, means that where there is some evidence of environmental or human health impact of PVC that reasonable alternatives should be used where possible. Furthermore, and more generally, this paper is intended to build greater awareness of this common building material.
To Increase The Use Of Recycled Content In Building Products: Reduce Health Hazards & Improve Feedstock Quality The recycling industry has made significant strides toward a closed loop material system in which the materials that make up new products today will become the raw material used to manufacture products in the future. However, contamination in some sources of recycled content raw material (“feedstock”) contain potentially toxic substances that can devalue feedstocks, impede growth of recycling markets, and harm human and environmental health. Since May 2014, the Healthy Building Network, in collaboration with StopWaste and the San Francisco Department of Environment, has been evaluating 11 common post-consumer recycled-content feedstocks used in the manufacturing of building products. This paper is a distillation of that larger effort, and provides analysis on two major feedstocks found in building products: recycled PVC and glass cullet. This research partnership seeks to provide manufacturers, purchasers, government agencies, and the recycling industry with recommendations for optimizing the use of recycled content feedstocks in building products in order to increase their value, marketability and safety. This report was prepared in support of a research session at the 2015 Greenbuild conference in Washington, DC.
Optimizing Recycling: Criteria for Comparing and Improving Recycled Feedstocks in Building Products Global industry has made progress toward a world in which more efficient use of resources, including recycling, helps to reduce impacts on the natural systems that support life. However, contamination of recycled-content raw material with potentially toxic substances reduces feedstock value, impedes growth of recycling rates, and can endanger human and environmental health. This paper provides findings and recommendations about how progress in resource use efficiency and recycling can occur along with the production of healthier building products. This paper is based on the review of eleven common recycled-content feedstocks used to manufacture building materials that are sold in California’s San Francisco Bay Area. It provides manufacturers and purchasers of building products, government agencies, and the recycling industry with recommendations for optimizing recycled-content feedstocks in building products to increase their value, marketability and safety.
Post-Consumer Cullet In California Source separation of waste streams and toxic content restrictions are crucial actions toward optimizing the value of recycled feedstocks in building products. HBN’s research on glass waste – known as cullet – reveals the multitude of economic and environmental benefits of these practices. The ability of fiber glass insulation manufacturers to incorporate cullet increases; the wasteful landfilling of discarded glass (nationally, only 28% is recycled) decreases. Manufacturers need less energy to produce insulation, leading to lower greenhouse gas emissions. Workers, surrounding neighborhoods, and the environment at large are exposed to fewer toxic contaminants. Post-Consumer Cullet in California is the second in a series of Healthy Building Network reports for the Optimizing Recycling collaboration.
Post-Consumer Polyvinyl Chloride In Building Products New HBN research reveals that legacy toxic hazards are being reintroduced into our homes, schools and offices in recycled vinyl content that is routinely added to floors and other building products. Legacy substances used in PVC products, like lead, cadmium, and phthalates, are turning up in new products through the use of cheap recycled content. Funding for research on post-consumer PVC feedstock was provided by StopWaste and donors to the Healthy Building Network (HBN). It was conducted using an evaluative framework to optimize recycling developed by StopWaste, the San Francisco Department of the Environment, and HBN. This briefing paper on post-consumer recycled PVC is a prequel to a forthcoming white paper by this new collaboration.
Asthmagens in Building Materials: The Problem & Solutions Asthma is a complex, heterogeneous disease, often of multifactorial origin. The Centers for Disease Control (CDC) reported that the number of people diagnosed with asthma grew by 4.3 million during the last decade. Nearly 26 million people are affected by chronic asthma, including over eight million children. Among asthma risk factors, health organizations have identified hundreds of substances that can cause the onset of asthma. Many of these asthmagens are common ingredients of building products like insulation, paints, adhesives, wall panels and floors. This paper identifies asthmagens found in building products, how people can be exposed to these substances, and what is known and yet-to-be known about the impacts of these exposures.
Phthalate-free Plasticizers in PVC This Healthy Building Network (HBN) Research Brief examines replacements for phthalate plasticizers in Polyvinyl Chloride (PVC) building materials. Plasticizers are added to PVC to make it flexible, but since they are not tightly bound to the PVC molecules, they migrate from PVC products. Phthalates, the most commonly used plasticizers in PVC, are known endocrine disruptors – chemicals that interfere with hormone signaling, which is especially critical to early childhood development. Additionally, many phthalates are known carcinogens and reproductive and developmental toxicants. Exposures to these toxic plasticizers from PVC products can occur throughout their lifecycle. Therefore, it is crucial that PVC products containing phthalate plasticizers be eliminated from the built environment.
Full Disclosure Required: A Strategy to Prevent Asthma Through Building Product Selection Asthma rates in the United States have been rising since at least 1980. Today, nearly 26 million people are affected by chronic asthma, including over eight million children. These rates are rising despite the proliferation of asthma control strategies, including indoor air quality pro- grams. The Centers for Disease Control (CDC) reported that the number of people diagnosed with asthma grew by 4.3 million during the last decade from 2001 to 2009. As asthma affects more people, it becomes increasingly clear that new strategies need to be considered, focusing on the prevention of asthma onset. Few strategies are in place that effectively prevents exposure to chemi- cals that cause asthma. Due to the complexity of this condition conventional efforts have largely focused on asthma management. Health organizations have identified a number of chemicals that are known to cause the onset of asthma, and are therefore labeled asthmagens. Since these chemicals are common ingredients of many interior finishes, like floors, carpets, and paints, it is possible to improve asthma prevention strategies by reducing or eliminating these chemicals from building materials. The Healthy Building Network (HBN) took a three-pronged approach that examined how pervasive asthmagen chemicals are in the built environment, what steps have been taken to address them, and what further actions are needed.
Avoiding Contaminants in Tire-Derived Flooring The benefits of reusing tire scrap are obvious. It diverts millions of tires from the solid waste stream. It saves energy and resources. It avoids new or additional toxic manufacturing inputs. Heaps of scrap tires are no better than reservoirs loaded with fly ash from coal fired power plants. Both fly ash and tire scrap are on the edge of being classified as hazardous wastes. Pollutants rise from festering pools of ash and smoldering piles of tires. The toxic compounds fall into nearby communities. Beneath these stews, heavy metals and polyaromatic hydrocarbons migrate into streams and aquifers. But does shifting these wastes indoors represent a positive alternative?
Avoiding Contaminants in Tire-Derived Flooring describes the origins and fate of crumb rubber used in building materials. It concludes that tires contain a host of toxic ingredients to which people may be exposed when this material is brought into homes, schools, gyms and offices.
Resilient Flooring & Chemical Hazards: A Comparative Analysis of Vinyl and Other Alternatives for Health Care Resilient Flooring & Chemical Hazards: A Comparative Analysis of Vinyl and Other Alternatives for Health Care addresses resilient flooring, evaluating potential health impacts of vinyl flooring and the leading alternatives – synthetic rubber, polyolefin and linoleum — currently in the health care marketplace. The study inventories chemicals incorporated as contents in each of the four material types or involved in their life cycle as feed- stocks, intermediary chemicals, or emissions. It then characterizes those chemicals using a chemical hazard-based framework that addresses: persistence & bioaccumulation, human exposure, and human toxicity.
Environmental Impacts of Polyvinyl Chloride Building Materials In the last 40 years, polyvinyl chloride plastic (PVC) has become a major building material. Global vinyl production now totals over 30 million tons per year, the majority of which is directed to building applications, furnishings, and electronics. The hazards posed by dioxins, phthalates, metals, vinyl chloride, and ethylene dichloride are largely unique to PVC, which is the only major building material and the only major plastic that contains chlorine or requires plasticizers or stabilizers. PVC building materials therefore represent a significant and unnecessary environmental health risk, and their phase-out in favor of safer alternatives should be a high priority. PVC is the antithesis of a green building material. Efforts to speed adoption of safer, viable substitute building materials can have significant, tangible benefits for human health and the environment. This report describes the full life cycle of PVC in the contemporary building industry from production to disposal.
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