The use of plastic in the built environment is an increasingly pressing issue affecting human health and the biodiversity of the planet. The impacts of chemicals on occupants across live-work-play settings stretches far beyond the four walls of a building and into surrounding communities. This occurs at the beginning of a material’s life cycle, right through to its end of life.

Environmental experts relayed some overwhelming statistics during a recent online discussion, hosted by Habitable, formerly the Healthy Building Network. Their advocacy comes as negotiators from around the globe seek to form an international treaty on plastic pollution.

The United Nations Environment Assembly adopted a resolution on March 2, 2022, to end plastic pollution by 2040. The treaty process is expected to be completed by this December.

“There are negotiations going on right now and there are obligations on the table to address plastics throughout their life cycle, starting with a call for production reduction,” said Bethanie Carney Almroth, a professor at the University of Gothenburg. “We need to bring down the amount of plastic that is being produced. It is unsustainable. Our planet can’t tolerate more; our bodies can’t tolerate more.”

Concern is mounting over a weak commitment to curb plastic production, as fossil fuel and petrochemical interests block progress. During the fourth session of the United Nations Intergovernmental Negotiating Committee on Plastic Pollution, which wrapped up on April 30, nations struggled to agree on the treaty’s scope and key substantive provisions. The final negotiation session is scheduled in November.

Almroth has been working with a group of 300 scientists to produce policy briefs and high-level summaries that support the delegates, who have since put forth that plastic pollution is serious on a global scale and negatively impacts the environment, social and economic dimensions of sustainable development.

Current world estimates for plastics to date are at 11 gigatonnes. “Building and construction is the second largest user of plastics and also one of the biggest users of PVC, which is at the top of the list of hazardous problematic polymers that maybe should be phased out,” Almroth urged.

In mid-March, a group of scientists in the European Union released a study funded by the Norwegian Research Council, outlining 16,000 different chemicals found in petroleum-based plastics. They found that 4219 of them have known hazardous properties, but more than 10,000 chemicals lack sufficient data. ​​

There is very little transparency and few reporting mechanisms, which also includes bio-based renewable sources that make up a smaller percentage. An estimated 99 per cent of all plastics are made from fossil fuels.

Last year, a study from the UN Environment Programme found that only 1 per cent of plastics chemicals are regulated in the world. Some hazards that plastics are labeled with include aquatic toxicity, carcinogens, mutagens, reproductive toxicity and endocrine-disrupting chemicals that interfere with a body’s hormones. “They’re persistent, bioaccumulative; they’re mobile, they’re toxic, they’re in our environment, they’re not breaking down, and they have impacts on both humans and organisms,” Almroth said.

The planetary boundaries framework, conceived in 2009, has since generated interest within science and policy, and inspired researchers like Almroth. It describes a set of nine earth boundaries that define the safe operating space for the stability of the planet and for humanity to continue thriving. As of 2023, data indicates that six of the nine boundaries have been breached.

Martha Lewis, senior architect and head of materials at Henning Larsen, said construction products have high environmental impacts, but many certified buildings that are build-as-usual fail to address these risks. Looking at biodiversity, pollution and climate change are key when approaching projects in order to make better choices that don’t overstep the safe operating space.

“It’s really where we should be putting our efforts right now, as opposed to trying to get the top score in a LEED platinum,” she said.

“These earth systems are deeply interconnected; the decisions we are making in terms of waste in our projects or the synthetic chemicals in the products we’re selecting also have very clear impacts on the loss of biodiversity.”

Global chemical usage is expected to double between 2019 and 2023 and double again by 2050, according to the UN Global Chemical Outlook. “This is all highly relevant for the construction sector because the sector is the number one in market for global chemical production, coming in at about 28 per cent,” said Lewis.

Yet there exists a lack of transparency in building documentation. Lewis says certification systems are failing the industry in how they ask consultants to screen for problematic substances.

Across the Nordic countries, she worked on an initiative in Denmark with top construction company NCC and SundaHus from Sweden on the use of problematic substances in building products and boosting material data collection. Much of the problem is related to glue found in adhesives and binding agents, as well as in construction materials, such as fillers, solvents, paints and lacquers and surface treatments.

She says the industry requires a detailed list of the chemical properties found in products and their resulting health effects, as well as declarations for all building products as they affect the end user.

One of the most proactive reports she has seen recently is from the Green Science Policy Institute, which charts PFAS uses in the built environment and material alternatives. PFAS serves as weatherproofing, corrosion prevention and stain resistance.

Addressing biosphere integrity on construction projects may seem daunting but she says a lot has to do with initial decisions to not build on green sites or agricultural lands. Build less, renovate, transform,” she urged.“Be very wise about specifications. . . for plastic specifications, be really clear about what kinds of undesirable properties won’t be admitted into the project.”

As the construction and design sectors set out to build more, it also becomes prudent to scrutinize the whole life cycle of materials and its environmental justice impacts.

Veena Singla, professor in the department of environmental sciences at Columbia University, cited a study on spray foam, a plastic polyurethane material that mostly contains hazardous isocyanates. Researchers found that facilities making spray foam ingredient generated millions of pounds of toxic chemicals in communities that are disproportionately low income. This occurred over one year.

Singla highlighted her work with the Agents of Change in Environmental Justice program at the school. Their mission is to empower leaders from historically excluded backgrounds in science and academia to reimagine solutions for a just and healthy planet.

“How can you start to bring in those who have been excluded and disempowered into partnerships and collaboration and leadership with the work that you do?” she posed. “If your work touches the built environment, you are impacting people’s health and justice as we move forward into the future.”

A study published in the Journal of the Endocrine Society this year found that healthcare costs attributed to four classes of chemicals used in plastics was $249 billion in 2018 alone in the United States.

“We need to look at who is benefitting and who is paying the price and make decisions thereafter,” said Almroth. “A lot of those decisions need to be top down.”

But in the move to a new materials economy, there exists a great deal of pushback from chemical producers due to economic interests, she finds, adding what is required are policy changes to hold companies accountable, support for those policies through voting, bold decision-makers, and more guidelines around transparency to help consumers make better choices.