Imagine a world without waste: no cardboard waste, no lost heat energy, no food waste. Imagine an industrial world that mimics nature where every end product is used as the starting material for something else. Imagine a world where, instead of following a linear progression from creation to disposal (cradle to grave), products follow a circular path (cradle to cradle). You are imagining the circular economy.

The circular economy is a systemic approach intended to eliminate waste in materials and energy flows throughout extraction, production, use, and disposal, and to repurpose outputs as useful inputs to other products. As sustainable practices become more popular and practical, the circular economy is quickly expanding in industry and will introduce additional hazards and considerations for the occupational health expert.

For example, as reported in Chemical & Engineering News, a European chemical company has begun making sodium bicarbonate using carbon dioxide from its gas-fired power plant in place of carbon dioxide bought from a vendor. This process change entailed redesigning the plant and ensuring the pharmaceutical-grade quality of the product. Neither of these requirements could have been achieved without upgrading workers’ skills and knowledge.

A more daunting example is plastics, 90 percent of which are not recycled using the mechanical methods currently available. A paper in a recent issue of Science describes the development of entirely new processes that use a combination of chemical oxidation and biological conversion. Workers must design the process, build the equipment, and learn how to operate and maintain the system—all of which require new knowledge and skills. Changes such as these place workers at the heart of the circular economy.

FROM OUTPUT TO INPUT The circular economy is rooted in the environmental movement that started in the 1960s. In 1966, the economist Kenneth Boulding proposed that production cycles adjust to the closed system of resources in the context of planet earth. Boulding was inspired by Rachel Carson’s observation that industrial expansion and environmental degradation were related. But the term circular economy did not appear for another twenty years.

An ongoing experiment in the generation and delivery of electricity in the Danish city of Kalundborg has come to signify the promise of the circular economy. Excess heat generated by a Kalundborg power station was originally condensed from steam and discharged to a nearby fjord. Beginning in 1972, this excess steam was diverted to an oil refinery, which sent its waste gas to the power station in exchange. As sharing developed through what came to be known as the Kalundborg Symbiosis, the power plant was able to direct its waste steam to a local pharmaceutical company, local greenhouses, a fish farm, and about 3,500 homes in the town. Without the steam from the power plant, these entities would have had to use fossil fuels for heating. Calcium sulfate, produced by the local oil company as a byproduct of desulfurization, is used by a French gypsum board maker. Elemental sulfur obtained by catalytic reduction of sulfur-containing gases is sold to a chemical company. Fly ash, which is produced when fossil fuel is burned, is used by a nearby concrete company. Currently, the Kalundborg Symbiosis provides more than 30 examples of how the output from one industrial process becomes the input for another.

TWO HALVES Drawing on ideas expressed in the 2002 book Cradle to Cradle: Remaking the Way We Make Things, the Ellen MacArthur Foundation describes the two halves of the circular economy as “things,” which consist of finite materials, and “biologicals,” which are made from recyclable materials capable of cyclic renewal. Things include cars, computers, toasters, and many other items that people discard at the end of their useful life. In the cradle-to-grave model, these items are often disposed of in landfills or simply put aside in places like auto graveyards and piles of tires. Biologicals include items such as food, water, and energy. It takes energy and water to grow food, which is consumed, excreted, and eventually returned to the soil where the process can start over. Placing food in a landfill disrupts this process.

To minimize natural resource extraction and unusable waste, significant changes are needed not only in how work is performed but also in what work is undertaken. As described in the 2013 book Junkyard Planet: Travels in the Billion-Dollar Trash Trade, in the recent past, most things were reused or repurposed many times before being discarded, and people used to fix things rather than throw them out. Repair shops used to be abundant, but few still exist, at least in part because of the limitations that electronics manufacturers place on what users can do with the devices they purchase. A circular economy would need many more repair technicians than are available today for items from electronics to lawn furniture. Imagine getting your phone updated and repaired instead of throwing it away with all its precious metal and plastic as well as embedded energy and water.

work that is productive, delivers a fair income, offers security in the workplace and social protection for all, contributes to personal development and social integration, and grants people the freedom to express their concerns, organize and participate in the decisions that affect their lives, and ensures equality of opportunity and treatment for all women and men.

MARY O’REILLY, PhD, CIH, CPE, FAIHA, is an adjunct assistant professor at the University of Albany School of Public Health, current president of Workplace Health Without Borders, and chair of the AIHA Stewardship and Sustainability Committee.
AUBREY ARAIN, PhD, is an industrial hygiene specialist at California Polytechnic State University and vice chair of the AIHA Stewardship and Sustainability Committee.

ERICA DOMBROWSKI, MPH, CIH, is a health and safety specialist at Insight Global in Redmond, Washington, and a member of the AIHA Stewardship and Sustainability Committee.