Spring 2025

A Few Words on the Past and Future of Plastics

Matthew Tymchak, M.S.

Despite the long and storied production history of plastic, plastic waste and related issues have risen to the forefront of environmental concern in recent years.  Although typically considered a recent societal technology, various plastic materials were formulated in the mid to late 1800s, and by 1909 the first patent for a synthetic plastic was filed by Leo Baekeland for the product “Bakelite,” which he labeled as the “material with 1,000 uses” (Baekeland, 1909; New York Times, 1909).  Other viable commercial plastic materials were fabricated early in the twentieth century and broader production generally began in the 1950s.

The physical properties of plastic materials vary widely, based on the type of polymerization and chemical additives used to create desirable characteristics for myriad industrial uses and consumer goods.”

Plastics are synthetic materials that are made of polymers.  A polymer is essentially a long chain of smaller molecules (monomers) that are typically bonded together in a repeating pattern, similar to the way that DNA chains are constructed to carry our genetic code.  While DNA is an example of a natural polymer, plastics are created through a series of chemical reactions in a laboratory, a process known as polymerization where chains are grown through different mechanisms.  The physical properties of plastic materials vary widely, based on the type of polymerization and chemical additives used to create desirable characteristics for myriad industrial uses and consumer goods.  For example, polyvinyl chloride (PVC) is produced in two main forms:  a rigid polymer, which is used in plumbing piping or window frames, and a more malleable material, which is used to insulate wires or in flexible vinyl siding, among other uses.  The latter form of PVC is created by adding plasticizers, or chemical additives such as phthalates, that give the product more flexibility.  Since a variety of chemical additives are used to alter plastic properties, including flame retardants, biocides, metals, and metalloids, plastic materials tend to be complex chemical mixtures.

Given the variable chemistry of plastics, including numerous chemical additives, a wide range of physical characteristics have made plastic materials particularly useful – they are lightweight, strong, flexible or rigid, durable under various environmental and industrial conditions, and long lasting.  As the number of applications and demand for plastics has risen, production costs have fallen and global production has increased significantly.  Although estimates vary, in general, global plastic production has increased exponentially since it became commercially viable in the 1940s and 1950s; more recently, this production is thought to have doubled to over 400 million tons (Mt) (Dokl et al., 2024).  Some studies have suggested that nearly half of all plastics produced have been made in the past 15 years, which may be an underestimation.

Although plastic waste typically has been associated with alleged ecosystem harm through marine and coastal pollution, recent concerns have turned toward potential human health risks from exposure to micro- and nanoplastics, tiny particles that break off from larger plastic materials, and to the chemical additives used to shape or mold plastics for various applications.”

Of these plastic materials, approximately 40 percent may be related to global packaging (Allen et al., 2020; Geyer et al., 2017).  Since packaging is deeply intertwined with modern society, as a way to keep food fresh, protect shipped items, etc., single-use plastics have come into focus for mitigation and management to reduce post-consumer waste and potential environmental and ecological impacts.  Although plastic waste typically has been associated with alleged ecosystem harm through marine and coastal pollution, recent concerns have turned toward potential human health risks from exposure to micro- and nanoplastics, tiny particles that break off from larger plastic materials, and to the chemical additives used to shape or mold plastics for various applications.

To address these public health concerns and to understand and manage plastic waste streams, federal, state, and international agencies, along with academic and governmental research, have begun to focus on the life cycle of plastic, including production and disposal, and how to limit environmental impacts.  For example, at the international level, the United Nations Environment Assembly (UNEA) is working to execute a multinational, legally binding agreement that will shift the reliance on single-use plastics to best practices that include sustainable alternatives, as well as reuse and new recycling technologies.  A UNEA resolution was adopted initially in March 2022; however, the fifth negotiating session aimed at finalizing the agreement is scheduled for August 2025, in Geneva, Switzerland (UNEA, 2022).

In the United States (US), the US Environmental Protection Agency (US EPA) promulgated a National Strategy to Prevent Plastic Pollution in 2024 (US EPA, 2024).  Although wide-ranging, key elements include innovations to material and product design, waste management and plastic capture/removal technologies, and the protection of waterways and oceans.  At the micro- and nanoscale, academic research has ballooned in recent years to include studies on many aspects of human health, ecological, and source identification issues for plastic particles less than five millimeters.  As with many environmental issues, California was the first state to take holistic action on the issue, unveiling a statewide microplastics strategy in 2022 and passing a law to limit the use of single-use plastic (California Ocean Protection Council, 2022).  Although actions to reduce plastic waste are underway at the international and individual state level, these efforts are likely to require scientific and policy inputs from a variety of stakeholders and could take a generation to implement.