Tag Archives: recycling

Mercury in Unexpected Products

by Hannah Horowitz

Written by Hannah Horowitz from Harvard University, this is the second in our series of Guest Scientist Blogs. Hannah is a graduate student in Earth and Planetary Sciences at Harvard University and a member of the Atmospheric Chemistry Modeling Group. Her research focuses on the environmental fate of mercury used in products and processes, and modeling the terrestrial mercury cycle.    Email: hmhorow@fas.harvard.edu        Website: http://people.fas.harvard.edu/~hmhorow/

When I first began my research on mercury used in products and processes, I was taken aback to learn that there were over 3000 known applications of the heavy metal [1]. What’s more interesting than the sheer number are some specific products containing mercury that are particularly surprising and unexpected. The vast variety of applications of mercury in the past and present are a result of its many unique chemical and physical properties. Its toxicity makes the disposal of mercury-containing products – some of which we may not realize are in our homes, schools, and businesses – challenging.

Some gym floors can release a lot of mercury.

Some gym floors can release a lot of mercury.

Polyurethane flooring used in school gymnasiums and indoor and outdoor tracks from the 1960s-1985 in the United States contain mercury used as a chemical catalyst [2]. One gym floor in Minnesota released mercury equivalent to breaking 280 compact fluorescent light bulbs per day, even 24 years after its installation [3]. However, measured concentrations and calculated total exposure in gyms tested in Ohio, Michigan, and Minnesota did not exceed levels that would result in health impacts [2, 4] from chronic (long-term) or acute (short-term) mercury exposure: 750 ng/m3 during 16 – 40 hours per week over a year, and 1800 ng/m3 for one hour, respectively [5]. Proper ventilation was key to reducing mercury levels [4]. However, average concentrations in Minnesota gyms were still around 200 times higher than typical outdoor background concentrations of 1.5 ng/m3 [6].

If a gym floor is believed to contain mercury, floor and air mercury concentrations should be measured, with help from the Agency for Toxic Substances and Disease Registry (ATSDR). If recommended exposures are exceeded, time spent in the gym should be limited, ventilation should be increased, and the floor may need to be removed (see [5]). Removal should be done carefully, as disturbing the floor may release more mercury than normal use [4]. Depending on its mercury content, the floor should be treated as hazardous waste or disposed in a lined landfill with leachate collection to prevent environmental releases [4].

Fishing lures

Fish lures can contain mercury.

Fish lures were once made using mercury.

Between the 1920s and the 1950s, fishing lures were made with visible liquid mercury inside to create motion and a shiny appearance to better attract fish [7]. Perhaps these mercury-containing fishing lures helped fishermen become exposed to methylmercury through the fish they successfully caught!

Now, care should be taken to avoid breakage and mercury release from the antique, fragile lures. For proper disposal, they should be brought to a hazardous waste collection program (varying state-by-state in the US) so the mercury can be removed and recycled [7].

Expected use in unexpected places

You can clearly see the mercury in this switch.

You can clearly see the mercury in this switch.

Some of the more typical uses of mercury – electrical switches and relays, lighting, and batteries – are widespread in many products that may be surprising. Mercury switches and relays help ovens and irons (pre-1990) shut off automatically [8, 9], thereby helping to prevent house fires. Similar switches and relays in cars brake with anti-lock brake systems (pre-2004) [10]  help prevent car crashes. However, these mercury-containing products may lead to environmental mercury contamination if their disposal is not handled properly. Electric lighting using mercury is ubiquitous – for example, LCD displays in cameras and sewing machines, UV lamps in printers, or fluorescent lamps in scanners and portable DVD players [8] to name a few. Button cell batteries present in children’s toys, calculators, and watches can also contain mercury [8, 11] and may be imported from other countries with less stringent mercury regulations [11].

The consumer should remove batteries from smaller products and contact their local municipality to find out about household hazardous waste collection services before throwing the object away [7, 12], so that they will not end up landfilled or incinerated along with general waste [13]. Electronics and larger appliances should also be collected if possible, and may be accepted by the original retailer depending on where you live (these services may or may not be free) [7, 12]. In the US, some automobile collection companies partner with End of Life Vehicle Solutions (or are mandated to do so by state law) to remove mercury-containing switches prior to turning the car into scrap metal, in order to prevent mercury emissions [10].

For more information, see the New England Waste Management Association’s mercury legacy products website.


  1. Nriagu, J. O. (1979), The biogeochemistry of mercury in the environment, Elsevier/North-Holland Biomedial Press, Amsterdam, the Netherlands.
  2. http://www.newmoa.org/prevention/mercury/projects/legacy/schools.cfm#gf
  3. http://www.newmoa.org/prevention/mercury/conferences/sciandpolicy/presentations/Herbrandson-Bush_Session3B.pdf
  4. http://www.atsdr.cdc.gov/HAC/pha/MercuryVaporReleaseAthleticPolymerFloors/MercuryVaporRelease-FloorsHC092806.pdf
  5. http://www.health.state.mn.us/divs/eh/hazardous/topics/mercury/hgflooringprofguide.pdf
  6. Slemr, F., E. G. Brunke, R. Ebinghaus, and J. Kuss (2011), Worldwide trend of atmospheric mercury since 1995, Atmospheric Chemistry and Physics, 11(10), 4779-4787.
  7. http://www.newmoa.org/prevention/mercury/projects/legacy/sport.cfm#fl
  8. https://imerc.newmoa.org/publicsearch/NEWMOA_IMERC.aspx#/CustomizedSearch
  9. http://www.newmoa.org/prevention/mercury/projects/legacy/appliances.cfm#ci
  10. http://www.newmoa.org/prevention/mercury/projects/legacy/automobiles.cfm#abs
  11. http://www.chem.unep.ch/mercury/GC-23-responses/GOV/Denmark-attachment-mercuryreport2004.pdf
  12. http://www.environment-agency.gov.uk/business/topics/waste/32096.aspx
  13. http://ec.europa.eu/environment/chemicals/mercury/pdf/study_report2008.pdf


Issue Overview: Mercury Waste

by Danya Rumore and Mark Staples

Danya and Mark here. During the INC5 negotiations, we’re covering issues related to mercury waste, mercury trade, and artisanal and small scale-gold mining (ASGM). We’ll be providing overviews of each of these issues separately, to make them more digestible. Here, in the first of our three Issue Overview installments, we provide an explanation of the mercury waste issue, what is already included in the draft treaty text about this issue, and what is likely to be discussed—and hopefully decided—in the week ahead.

The use of mercury in products and processes has a long history, with evidence of human use of mercury dating as far back as 5000 BCE.

Although awareness of the health and environmental impacts of the toxic metal has resulted in reduced use of mercury in many industries, it is still present in many products and processes, including light bulbs, cosmetics, and chlor-alkili production. Many mercury-containing products eventually end up in landfills or other waste sites, and leftover mercury compounds from industrial processes often enter the waste stream. When deposited in landfills, mercury-containing waste, over time, releases mercury into the environment. More problematically, incineration and the combustion of mercury containing waste can result in a sudden and significant release of mercury directly into the atmosphere. According to the UNEP Global Mercury Assessment 2013, waste-related sources made up approximately 5% of global anthropogenic emissions in 2010.

While mercury in the waste stream is a pressing issue, the good news is that solutions are available. Controlling and reducing the use of mercury in products can prevent mercury from entering the waste stream in the first place. Since significant amounts of mercury already exist in products and waste, efforts to capture, contain, and recycle mercury-containing wastes are necessary.  Such efforts are already underway, such as the US EPA’s fluorescent lamp recycling program and guidelines in case of releases and spills. Further, emissions controls on waste incinerators can greatly reduce mercury output from waste combustion and should be implemented wherever possible.

During the INC4 negotiations in Uruguay, progress was made on the question of how to address mercury waste in the globally binding agreement. Most prominently, the draft treaty text includes the provision that all parties to the agreement shall take appropriate measures to manage mercury waste in an environmentally sound way, in accord with the Basel Convention. This part of the treaty seems to be generally accepted, although the question of how to manage the transport of mercury across international boundaries in circumstances where the Basel Convention does not apply remains unresolved.

On Monday, the articles of the draft text relevant to mercury waste were introduced in the plenary session. Switzerland, with support from the EU, called for bringing all definitions and procedures for the trans-boundary movement of mercury in line with the Basel Convention. Lebanon expressed a desire for standards specific to mercury waste disposal, and Chile called for a more clear definition of “mercury wastes”. Additionally, whether and how to make parties who have not signed or ratified the Basel Convention comply with transboundary waste movement regulations was discussed.

The draft treaty also includes text related to the identification and management of sites contaminated by mercury. This topic appears to be much more contentious than the topic of waste management. While the draft treaty includes language indicating that action shall be taken to reduce the risk presented by contaminated sites, it remains to be seen whether capacity building and financial and technical assistance will be a necessary condition of including this in the agreement. In the plenary, Japan requested deletion of the capacity building and assistance provision, while Brazil, Iran and Morocco called for its inclusion.

At the conclusion of the plenary session on the second day of official negotiations, the Chair elected to move discussions of the treaty articles on storage, waste, and contaminated sites to the contact group for selected technical articles. Before addressing these issues, the contact group must first work through the products and processes articles. For now, storage, waste, and contaminated sites are on hold. We anticipate they will be picked up again late Tuesday evening or, more likely, early in the day on Wednesday.

As developments emerge, we’ll be posting updates here on our blog and via twitter @markdstaples and @DanyaRumore.  Stay tuned!