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Saturday, November 16, 2019

Exposed: Toward a BPA-free future

What will it take to rid our store shelves of BPA and its equally hazardous cousins?
hungry marc rodriguez GIFA percussion of metal-on-metal echoes through the lab as empty food cans drop one by one off a conveyor belt and into rounded pockets of a rotating blue cogwheel.

As the cog circles counterclockwise, the can spins rapidly. Two spray guns blast a liquid lining inside before the can falls onto another conveyor belt and then shoots up a chute to a final belt that carries it down into a large curing oven.

These now freshly baked cans, their interiors a toasted brown, are part of a series of validation tests at the coatings company Valspar, recently acquired by Sherwin-Williams. For more than a decade, Valspar has worked to develop safe and effective replacements for food and beverage can linings historically made with bisphenol A.

Until about a decade ago, a layer of BPA-based epoxy about 20 times thinner than a human hair coated the inside of nearly all food and beverage cans. This shield excelled at preventing corrosion and, therefore, protecting us eaters and drinkers from deadly spoilage. 

But evidence has piled up that bits of the substance can leach from that lining and into soda, soups, Spam and sardines, among other canned products. 

And studies from academic laboratories show that BPA may mimic and mess with our hormones even at the tiniest of doses — increasing risks of cancer, diabetes and infertility, as well as derailing the normal development of a child's brain. That science suggests that our bodies are so sensitive to this compound that the use of BPA needs to be eliminated, not just reduced, to protect our health.

"The regulatory agencies are saying BPA is just fine," Tom Mallen, global director of packaging regulatory affairs at Sherwin-Williams, told EHN. "But there is a large voice contradicting that."

Despite this insistence from regulatory agencies of BPA's safety, some companies have been moving ahead with alternatives. With help from developments in green chemistry, and driven largely by consumer demand and policy-making outside of Washington, they are beginning to remove BPA and other endocrine-disrupting chemicals from store shelves. Still, progress is slow as the stakes are high. 

The global BPA market continues to grow and is predicted to surpass 7 million tons by the end of 2023. In addition to cans, the chemical is found in cash register receipts, dental sealants and the polycarbonate plastic used in reusable water bottles, among other products. 

Adding to the challenge: a safe and effective BPA replacement for one product may not be a suitable swap for others. And many of the alternatives that allow a manufacturer to proclaim a product "BPA free" show health effects that are just as bad, if not worse, than BPA. What will it take to ensure only our natural hormones are running the show in our bodies?

An investigation by EHN has uncovered details of a stand-off between academic scientists and federal regulators that intensified with the launch in 2012 of a multimillion-dollar government-led project called Consortium Linking Academic and Regulatory Insights on BPA Toxicity, or Clarity. 

Academics had increasingly voiced disagreement with the actions, or lack thereof, of the U.S. Food and Drug Administration with regard to the hormone imposter. The methods used by FDA regulators to assess the safety of chemicals, they have argued, remains decades behind the science. 

Clarity aims to help these critics and regulators reach a consensus on BPA's potential health harms, and to inform future testing and regulation of BPA and hundreds of other endocrine-disrupting chemicals including BPA replacements such as bisphenol S, or BPS.

So far, no such luck. As EHN detailed—via hundreds of emails obtained through Freedom of Information Act requests, along with dozens of studies and reports, and more than 50 conversations with scientists, regulators and other stakeholders—the FDA appears to have made up its mind on BPA before Clarity even began. 

"They already put a stake in the ground and they don't want to budge," Heather Patisaul, a professor of biology at North Carolina State University and a Clarity investigator, told EHN.

Here at Sherwin Williams' Packaging Global Technical Center in Pittsburgh, the tone is more positive. The company is among those actively pursuing BPA alternatives that won't disrupt our hormones. 

Mallen and four others sit around a table in the center's conference room, a short walk from the building with the Rube Goldberg-like can machinery. This room's walls display collections of consumer products that Valspar has coated over the decades, grouped by color of the brand's label.

There is the red assemblage: a metal bottle of Budweiser Select, a can of Campbell's Chunky BBQ seasoned pork, a Coca-Cola can. Further down the wall are shelves showcasing cans of San Pellegrino Limonata, Bumblebee solid white albacore tuna and Friskies Shreds with ocean whitefish and tuna — all with varying shades of yellow. 

Nearly every product displayed is lined with BPA. The substance has been an integral component of modern commerce for decades. Yet a major shift is underway for the half a billion or so food and beverage cans currently made each day in North America.

Over a lunch of sandwiches, chips and blue cans of water, Mallen goes on to describe his company's decision to not wait on regulators and to enlist the help of some of the staunchest BPA critics in the development of their next generation of BPA-free can linings. 

Starting in 2008, through a process they call "safety by design," Valspar went looking for a high-performing chemical compound that was not only less likely to leach from the inside of a can but also lacked the hormone-mimicking behavior of BPA or BPS. The winning compound: tetramethyl bisphenol F (TMBPF).

Academic scientists have tested the compound for a range of endocrine disruptive activities — effects that regulators do not typically consider in their safety assessments — and Valspar is now using TMBPF as the basis for ValPure V70, its newest family of can linings. 

The BPA-free epoxy lines those oven-cured cans, our blue cans of water and a small but increasing share of the food and beverage can market across the United States. Sherwin-Williams is applying for approval in the European Union.

"The industry's thinking was to not talk to critics, and to marginalize them," said Mallen. "We decided that wasn't a productive approach."

Related: Deciphering the real message about BPA

This is part 4 of a 4-part investigation of the science surrounding the chemical BPA and the U.S. regulatory push to discredit independent evidence of harm while favoring pro-industry science despite significant shortcomings.