Dentistry Aims to Go Green

December 11, 2019
Photo of a woman with a bamboo toothbrush

During Harvard’s recent Worldwide Week, Donna Hackley, DMD, MA, an instructor in Oral Health Policy and Epidemiology at HSDM, was featured on a panel of global and community health experts titled, “Climate Change, the Environment, and Oral Health.” Hackley spoke candidly about the bi-directional relationship between environmental health and oral health through the lens of health equity. Dentistry, as an industry, impacts our planet’s environmental health, which affects oral health. Her presentation left the audience wondering what they could do to help eliminate some of this waste.  

Hackley’s team, which includes Jenna Mu, a sophomore at Boston College (Biology), and Amini Papike, a fifth year student at the University of Rwanda School of Dentistry, found that a shocking and often overlooked source of the pollution that compromises food, water, and air quality comes from the international dental community. In a recent summary of their research, the team cited plastic, mercury, lead, and silver waste among the most common pollutants produced by the dental industry.  

Donna Hackley presents on dental waste and its impact on the environment and climate“These pollutants threaten the health of organisms and humans, especially the developing young, as well as the stability of various economies,” Hackley said. 

Plastic waste is a particularly common type of dental waste. Frequently used consumer dental products, such as toothbrushes and toothpaste, are typically made of plastic and are remarkably challenging to recycle.  

“Globally, 23 billion toothbrushes and their wrappings are discarded every year, and in the U.S. alone, the number of discarded toothbrushes is enough to circle the earth four times,” the team reported. “Toothpaste tubes are also not recyclable, as they typically contain an interior layer of aluminum. Toothpaste itself contains harmful plastic microbeads, and 8 trillion microbeads are released into aquatic environments daily from the U.S., enough to cover over 300 tennis courts.” Hackley pointed out that dental offices produce plastic waste each time they use and discard patient bibs, headrest covers, syringes, and even patient “goodie” bags.  

Mercury, lead, and silver also pose a threat to our ever-changing environment. Mercury is a major component of dental amalgam and is Jenna Mu, a student at Boston College, presents the team's research on dental waste at a poster sessionplaced and removed from teeth every day in dental offices around the world. “Patient chairs can generate up to 4.5 grams of mercury daily, and the improper disposal of the mercury is a major concern,” Hackley said. “Through landfill, wastewater, or incineration disposal methods, mercury can pollute the land, water, and air, respectively. Indeed, in some U.S. wastewater treatment facilities, dental wastewater streams contribute up to 70 percent of the total daily mercury load.” The lead and silver products that are found in x-ray materials, including films and solutions, are also of concern, particularly in countries that cannot manage proper disposal. 

Hackley and her team are encouraging dental offices around the globe to conduct thorough dental clinic waste audits. The goal is that practices will estimate the total amount of domestic as well as medical waste they produce and determine ways to reduce that waste. As new, environmentally friendly products become available, Hackley also hopes that dental offices will select alternatives to common plastic products.  

In response to these findings, Harvard School of Dental Medicine recently established the HSDM Sustainability Committee, which will focus on ways that HSDM can make impactful changes in regards to its environmental impact. The committee’s first initiative will be to tackle domestic, non-medical waste. Students, faculty, and staff are committed to evaluating HSDM’s own dental waste, and hope to set a standard for this community moving forward.  

HSDM students sort through plastic dental waste to determine ways to reduce and recycle dental materialsJennifer Lee, DMD21, is a student representative on HSDM’s new sustainability committee, and has played an active role in determining the group’s goals for the coming year. “Our initial plan includes community education, waste reduction, and waste diversion,” said Lee. “At this point, we have conducted a preliminary waste audit, which revealed that the primary sources of waste in the pre-clinical laboratory are: gloves, disposable gowns, masks, paper, and paper towels. Our goal for 2020 is to create a measurable reduction in pre-clinical waste production and expand to other areas of HSDM.” 

With procedures being put into place here at HSDM to measure and reduce domestic and dental waste, Hackley highlights the importance of participation of dental professionals around the world. “The international dental community must commit to preventing and reducing dental waste. Any adverse environmental impact resulting from our professional activities disproportionately affects the most vulnerable populations globally. This is about equity. Thoughtful waste management is no longer just a nice idea, but a moral and ethical imperative to protect the environment and every organism living in it.”  

Access Hackley's full report here.