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Connecting the dots between plastic, mercury, asbestos and PFAS: A new report confirms PVC’s toxic lifecycle

Plastics production imperils life on earth in many ways, from the pursuit of fossil fuels to the pollution of the oceans. All petrochemical plastics exact some toll in their manufacture. But there is one type of plastic that is particularly harmful: polyvinyl chloride, commonly known as vinyl or PVC.

A new catalog of the world’s chlorine and related plastics industry confirms PVC’s long-standing status as the “poison plastic.” PVC can’t be made without using and releasing some of the world’s most toxic substances, including asbestos, mercury, and PFAS (per- and polyfluoroalkyl substances).

An Open Access Global Inventory of the PVC Plastics Industry

Healthy Building Network (HBN) just completed an 18-months-long research project called Chlorine and Building Materials: A Global Inventory of Production Technologies and Markets. Building product manufacturers, wanting to better understand their supply chains, financially supported this initiative but had no editorial control over it. The end results – spreadsheets, a Google map, and reports – are open access data, and are free to use with attribution to HBN.

The project spotlights the world’s largest chlorine and PVC factories. It details the owners, capacities, technologies, and markets served by 146 chlorine producers. It reveals the chlorine sources for 113 PVC plants. It also considers the pollution caused by this production. The bottom line is that all PVC resins are produced with one form of toxic technology or another, whether it be asbestos, mercury, or PFAS.

Step 1: Making Chlorine – A Toxic Soup

The first step of production – turning brine into chlorine and caustic soda at chlor-alkali plants – is highly energy intensive. The largest chlor-alkali plant in Germany – Dow’s plant in Stade – for example, consumes 1% of Germany’s electricity. In China, the government has built some of the world’s largest chlor-alkali plants in the country’s coal mining regions. It also built alongside these plants huge coal-fired power plants to fuel the chlor-alkali process.

Almost half of the world’s chlorine is used to make PVC. Despite this dependence, life cycle analyses of PVC have not included its share of the energy consumed in the chlor-alkali process. This is not just a technical point: Because of this omission, climate change studies undercount PVC’s contribution.

Every chlor-alkali plant in the world uses either mercury, asbestos, or PFAS.

Mercury: About 3% of the world’s chlor-alkali capacity uses mercury cells, a technique that dates to the 1800s. Two mercury cell plants still operate in the United States: Westlake Chemical’s plant in Proctor, West Virginia, and Ashta Chemical’s plant in Ashtabula, Ohio. The US, Germany (where BASF and Evonik run mercury cell units), and Russia, are the world’s leading mercury cell laggards.

Asbestos: About 18% of chlorine is produced using asbestos diaphragms. The U.S., Germany, and Russia are also among the last countries to be using asbestos diaphragms in the production of chlorine. Dow operates the largest chlor-alkali plant in Europe using asbestos diaphragms. Producers in the U.S. are particularly dependent upon asbestos. Most of these plants are in Louisiana and Texas. For years, the U.S. chemical industry imported asbestos from Brazil. The mine in Brazil closed in February; now, the industry depends upon an asbestos mine in the Ural Mountains of Russia that is owned by a friend of President Vladimir Putin. Close relations between the petrochemical industry and the current administration in Washington appear to be forestalling possible restrictions through the new TSCA process. The EPA soon will release its draft Risk Evaluation for asbestos. So far, the agency has ignored concerns raised by Safer Chemicals, Healthy Families, Environmental Health Strategy Center, Asbestos Disease Awareness Organization, and many others.

PFAS: The alternative to mercury or asbestos is PFAS. Over 40 million tons of production capacity in HBN’s inventory comes from PFAS membranes or diaphragms. That’s nearly 80% of all chlorine production. Concerns about this class of substances are growing by the day. The deliberate production of long-chain PFAS – PFOA and PFOS – is being regulated but the rest is not. In a new Frontiers in Chemistry journal article, Matthias Kotthoff and Mark Bücking warn that “the ban or restrictions of individual molecules will lead to a replacement with substitutes of similar concern.” They point out how little is known about the PFAS class a whole and the “Dark Matter” that arises from its production and use. “The amount, identity, formation pathways, and transformation dynamics of polymers and PFAS precursors are largely unknown,” they write.

In Cape Fear, North Carolina, Chemours manufactures a PFAS membrane called Nafion that’s used in chlor-alkali production. EPA recently discovered byproducts of Nafion in the Cape Fear River and in groundwater near the Chemours plant. The North Carolina Department of Environmental Quality (DEQ) ordered Chemours to stop the release of fluorinated compounds including Nafion byproducts. The DEQ said, “little information is known about the potential health effects of GenX [another PFAS produced at the Chemours plant] and less is known about the Nafion byproducts.”

About half of the world’s Nafion membrane resins are used in chlor-alkali production, the other half in fuel cells. According to manufacturers, between 4 and 6.7 grams of “membrane resin” are released per ton of chlorine produced. Worldwide, with PFAS-based production capacity of over 40.4 million tons per year, the chlor-alkali industry may be releasing over 161 tons of membrane resin per year. No public information could be found that addresses the fate of Nafion and “dark matter” released from chlor-alkali production. There are no regulations or reporting requirements on the discharge of Nafion or any other PFAS from chlor-alkali plants into water. Environmental health groups like SCHF say this is a major regulatory gap that EPA must fix.

Step 2: The Vinyl Chloride Monomer (VCM) Process

The next step in the PVC supply chain – the production of vinyl chloride monomer (VCM) – introduces even more toxic pollution and fossil fuel consumption. In these processes, chlorine is reacted with a carbon source. There are two ways industry does this: the ethylene and acetylene routes.

Ethylene, Dioxins, and PCB’s: Outside of China, the ethylene process is almost always used. In this process, chlorine is reacted with ethylene (usually obtained from fracking sites in the US) to produce ethylene dichloride, which is processed to form VCM. The ethylene route of production releases a wide range of toxic chlorinated pollutants — including dioxins, polychlorinated biphenyls, carbon tetrachloride, and hexachlorobutadiene — that are among the public and environmental health community’s top priorities for elimination.

Acetylene and Mercury: In China, the acetylene process dominates production, and is quite different. Coal, not gas, is the carbon source. Combining coal with chlorine requires a series of reactions, the last of which uses a mercury-based catalyst. Over 80% of China’s PVC is made using mercury catalyst. In addition to the suite of chlorinated pollutants usually associated with VCM, the acetylene process releases mercury. The PVC industry is now one of the two largest consumers of mercury in the world due to this process. Coal-to-PVC plants have proliferated in interior China in the past 15 years. China exports acetylene-based PVC to the US in the form of building products, like vinyl floors, and other consumer products, including toys.

China has surpassed the US as the world’s leading producer of PVC. Due to cheap coal and, in the US, fracking, these two countries dominate the global industry. They produce more than half the world’s PVC.

Step 3: Accountability in the marketplace

HBN’s Chlorine & Building Products research provides a platform for a full accounting which the industry – including retailers that sell PVC products – has avoided. PVC is prevalent because it is cheap. It is cheap because it consumes the lowest-cost fuels on earth, in places where the lines between industry and government have nearly vanished and regulations are thin. Societal and environmental costs are not built into the price of PVC. But it is possible to consider these negative externalities in the marketplace.

Fortunately, safer alternative products, with far less toxic life cycles than PVC, exist. HBN’s Home Free project provides guidance for many types of building materials. Other good resources for avoiding PVC (and potentially regrettable substitutions) include the Healthier Hospitals Initiative’s list of interior finishes and the Ecology Center’s HealthyStuff product database, and CHEJ’s Back-to-School Guide to PVC-free School Supplies. And Safer Chemicals, Healthy Families’ Mind the Store campaign is constantly identifying toxic products in retail stores and pressing for their removal. Each of these initiatives reveals that safer products are widely available. When you must shop, please take this information into account.