All people and the planet thrive when the environment is free of toxic chemicals (*)
We talk of sustainable procurement, of healthy buildings, of greater transparency in what we specify and procure and of eliminating toxic materials from construction but, as the recently published Healthy Building Network overview of the global Chlorine and PVC markets demonstrates, we have a long way to go – and its scary. (Part One of the HBN report covers North and South America, Africa, and Europe, with Part Two later this year covering Asia and Rest of the World)
As the HBN notes:
- Chlorine is inherently highly toxic.
- Chlorine production uses and releases mercury, asbestos, or other highly toxic pollutants. (Mercury use has significantly declined, but the US still imports 480 tons of asbestos per year for diaphragms, primarily from Russia.)
- Combining chlorine with carbon-based materials creates environmental health impacts that are difficult if not impossible to solve.
And, it is the the building sector is propping up a ‘toxic’ chlorine and PVC global market …
Market data indicate that, as many industrial uses of chlorine decline due to environmental health concerns, market de-selection, and stricter regulations, the market share of chlorine used in PVC and certain other products has increased. Today, most of the chlorine produced in the world is used to make four plastics: PVC, epoxies, polycarbonate, and polyurethane.
PVC contains nearly 60% chlorine by weight, and most PVC is manufactured for use in building products. Indeed, chlorine and building industry analysts agree that because building trends drive PVC demand, and PVC demand drives chlorine production, it can fairly be said that the building-products industry drives chlorine production levels and its attendant environmental and human health impacts.
Chlorine Production Technologies
There are four industrial processes that can be used to create chlorine gas. The oldest technologies use either mercury or asbestos. The two newer technologies (introduced in the 1970s) use diaphragms or membranes coated with per- and polyfluoroalkyl substances (PFAS).
Most chlorine produced in Europe and Africa comes from PFAS-coated membrane technology. The main chlor- alkali producers in Africa do not use mercury cells or asbestos diaphragms. In Europe, exemptions to regulations that otherwise prohibit asbestos and mercury-based technologies allow the largest chlor-alkali plant to continue to use asbestos, and at least five other locations will continue using mercury into the foreseeable future.
Approximately 45% of chlorine production capacity in the Americas, including 8 of the 12 largest plants in operation, use asbestos diaphragms. Seven of these 8 are located on the US Gulf Coast. The other is in Brazil, which is phasing out asbestos mining. The US plants have relied upon Brazilian asbestos and soon will depend upon asbestos mined in Russia.
While all petroleum-based products are associated with industrial pollution, the introduction of chlorine and chlorine-based substances adds an additional pollution burden that is uniquely associated with chlorine.
This begins with the manufacturing of the chlorine itself. Over 400 tons of chlorine gas are released per year by chlor-alkali facilities in the US and Canada. Asbestos and mercury releases are well documented from the plants employing those antiquated technologies, which pollute the environment and poison people throughout the lifecycle, from mining, to distribution, to use, and finally, to recycling or disposal operations.
… “forever chemicals”
The more modern technologies employ machinery coated with per- and polyfluoroalkyl substances (PFAS). PFAS are highly toxic and long-lived chemicals that are coming under increasing scrutiny. The Harvard School of Public Health has issued warnings about these “forever chemicals” as used in consumer products such as Teflon, and as stain and water repellents on carpeting and upholstery. Because PFAS are not regulated at the point of use at chlorine manufacturing plants, there are no reported PFAS emissions or waste. However, PFAS have been detected in the effluent from the main US manufacturer of membranes used in chlorine plants.
… the additional burden of PVC production
The use of chlorine for PVC production creates additional burdens, generating organochlorine waste and by products. These chemicals are not broken down by natural systems, and typically last for generations in the environment. Many of them also build up in the ecosystem, including fish, wildlife, and humans, and are toxic at low doses. In addition to polluting the local environment near the facilities that release them, these chemicals can also be transported around the globe. One of them, carbon tetrachloride, is an ozone-depleting chemical and potent global-warming gas.
Additionally, PVC plastic production plays a role in the growing concern about microplastic ocean pollution through the factory discharge of PVC resins, in the form of small plastic pellets, into waterways.
Moving Forward: “When we know better, we can do better”
While environmentalists, building owners, architects and designers, and building-product manufacturers differ in their opinions on the avoidance of PVC, there is widespread and growing support for the elimination of mercury and asbestos from the supply chain of PVC and other chlorine-based products. A public global inventory of chlorine and VCM producers, and associated documented pollution, is a necessary first step for taking action.
HBN is providing this report, and accompanying online materials, spreadsheets, and map, as full open-access content. This data can help manufacturers to avoid chemicals derived from toxic technologies, scientists to fill gaps in understanding on the material flow of pollutants like PFAS and carbon tetrachloride, and communities to connect with others who, like them, face daily pollution from the chlorine and PVC industry.
(*) HBN Vision: All people and the planet thrive when the environment is free of toxic chemicals
See also the excellent Lloyd Alter detailed article in TreeHugger:
Making vinyl and other plastics releases dangerous pollutants. Do they belong in green buildings?
PVC, often called vinyl, has long been controversial in the sustainable design and green building worlds. It’s red-listed in the Living Building Challenge and the Cradle to Cradle certification system, and the attempt by the LEED people to limit its use in buildings almost brought down the whole certification system.