Mercury Reduction Project
Dept of Chemical Engineering
University of New Hampshire
Phone Number: 603-862-4467
Facility: UNH EH&S
Contact Person: Bradford Manning
Phone Number: 603-862-2571
Faculty Advisor: Dr. Ihab Farag
Phone Number: 603-862-2313
Mercury is a naturally occurring metallic element and a potent neurotoxin. It is used
extensively in many products and processes due to properties that enable it to conduct
electricity, measure temperature and pressure and alloy with other metals. It can enter
surface waters through atmospheric deposition and be released into the air through
combustion, incineration, or manufacturing processes, and may eventually be deposited
into lakes. Exposure to elemental mercury vapors can cause acute respiratory problems,
which are followed by neurological disturbances and general systemic effects. Acute
exposure to inorganic mercury by ingestion may also cause gastrointestinal disturbances
and may affect the kidneys. So mercury seriously threatens the health of humans and
My major mission is to identify mercury-containing compounds and instruments such as
elemental mercury, test equipment, lighting, thermometers, manometers etc. that are
present on campus and to recommend strategies to eliminate elemental mercury from
campus inventory, and where possible, replace mercury containing instruments with non-
Mercury is a common element that is found naturally in a free state or mixed in ores.
Because mercury is very dense, expands and contracts evenly with temperature changes,
and has high electrical conductivity, it has been used in thousands of industrial,
agricultural, medical, and household applications. Major uses of mercury include dental
amalgams, tilt switches, thermometers, lamps, pigments, batteries, reagents, barometers,
manometers, and hydrometers. It also may be present in rocks or released during volcanic
Mercury can enter the environment from a number of paths. For example, if a mercury-
containing item is thrown into the garbage, the mercury may be released into the
atmosphere from landfill vapors or, or the mercury may vaporize if the trash is
incinerated. If mercury is flushed through a wastewater system, the mercury will likely
adhere to the wastewater sludge, where it has the potential to volatilize and be deposited
elsewhere. Mercury can enter the atmosphere through these various means because it
evaporates easily. It can travel through the atmosphere in a vaporized state.
Once mercury is deposited into lakes and streams, bacteria convert some of the mercury
into an organic form called methylmercury. This is the form of mercury that humans and
other animals ingest when they eat some types fish. Methylmercury is particularly
dangerous because it bioaccumulates in the environment. Bioaccumulation occurs when
the methylmercury in fish tissue concentrates as larger fish eat smaller fish.
Methylmercury interferes with the nervous system of human body and can result in a
decreased ability to walk, talk, see, and hear. In extreme examples, high levels of
methylmercury consumption have resulted in coma or death. Many animals that eat fish
also accumulate methylmercury. Mercury can interfere with an animal's ability to
reproduce, and lead to weight loss, or early death.
Identify mercury-containing compounds and instruments such as thermometers,
thermostats, switches, manometers, barometers, hydrometers, sphygmomanometers, and
fluorescent lamps etc. that are present on campus.
Recommend strategies to eliminate elemental mercury from campus inventory, and
where possible, replace mercury-containing instruments with non-mercury instruments.
Research possible mercury containing sources such as thermometers, thermostats,
switches, manometers, barometers, hydrometers, and fluorescent lamps etc. by searching
Perform a building to a building site survey on campus for those sources. During the site
survey, meet with thirteen department chairs to discuss the mercury project and review
objectives. The following is the departments what I met:
Dean, College of Life Sciences and agriculture (COLSA)
Farm Services Department
Chemical Engineering Department
Facilities Design & Construction
Energy Management Department
UNH Health Service
Animal Nutritional Sciences
Develop an inventory of all elemental mercury and other mercury compounds and
instruments that contain mercury for those buildings. (See attached reports)
Recommend methods to reduce and recycle these mercury sources.
Instruments containing mercury on campus
Description: Thermometers include fever thermometers for home and medical use,
laboratory thermometers, and industrial thermometers.
How to Identify: The bulbs of thermometers containing mercury are usually silver in
color. Types of mercury thermometers on campus include: Laboratory and weather
Amount of Mercury: typical fever thermometers contain about 0.5 grams of mercury
each, while laboratory thermometers contain up to 3 grams of mercury.
Pollution Prevention Options: Mercury-free alternatives are digital, aneroid, and alcohol
thermometers, and for most applications they are as accurate as mercury thermometers.
Digital thermometers tend to last longer, however, because they are less likely to break.
Safe Handling: Mercury thermometers are easily broken when not handled carefully. If
the break occurs, use two pieces of paper or two razor blades to scoop it up from a
smooth surface. An eyedropper or a mercury vacuum can also be used. Mercury spill kits
are available from safety equipment supply companies for large mercury spills.
Safe Disposal: Save old or broken thermometers in an air-tight container. Homeowners
can use local household hazardous waste collection programs for disposal. Businesses
should deliver their thermometers to a consolidation site or arrange for a transporter to
take them. Contact your county or state environmental office or solid waste office for
services available in your area. Also, save the invoices that track your waste that include
the following information: date of shipment, amount of waste, location from where waste
is shipped, and destination of shipment.
Description: Mercury-containing thermostats use mercury tilt switches.
How to Identify: Most thermostats, other than electric thermostats, contain mercury. To
determine if a thermostat contains mercury, remove the front plate. Mercury-containing
thermostats contain one or more small mercury switches. Thermostats are generally
mounted on walls and easily found.
Amount of Mercury: About 3 grams of mercury are in each mercury tilt switch. Most
thermostats have one switch; some have two, and up to six switches are possible.
Pollution Prevention Options: Programmable electronic thermostats are mercury free,
and they are more energy-efficient than the mercury model. Look for programmable
electronic thermostats that have the Energy Star label.
Safe Removal: Remove the entire thermostat using a screwdriver and a pair of wire-
cutters and store safely. Don't remove the switches from the thermostat, or dismantle the
Safe Disposal: Store the entire thermostat in a marked container until it can be sent for
proper disposal. In many states, the Thermostat Recycling Corporation operates a
recycling program utilizing heating, ventilation and air conditioning (HVAC)
wholesalers; eventually this program will be in operation nation-wide. The wholesalers
consolidate thermostats from contractors and send them to recyclers; only whole
thermostats are accepted. Contact your HVAC wholesaler to find out whether you can
drop off thermostats. If the thermostat Recycling Corporation program is not yet
operating in your state, inquire with your state or local hazardous waste program for
information about where you can send mercury thermostats for proper disposal.
Description: Mercury is contained in temperature-sensitive switches and mechanical tilt
switches. Mercury tilt switches are small tubes with electrical contacts at one end of the
tube. As the tube tilts, the mercury collects at the lower end, providing a conductive path
to compete the circuit. When the switch is tilted back, the circuit is broken.
How to Identify: A mercury tilt switch is usually present when no switch is visible. They
are used in thermostats, silent light switches, and clothes washer lids.
Amount of Mercury: About 3.5 grams of mercury are contained in a small electrical
switch. Industrial switches may contain up to 8 pounds of mercury.
Pollution Prevention Option: Alternatives to mercury switches include hard-contact
switches and solid-state switches.
Safe Removal: Remove switches from appliances very carefully so as not to release any
mercury into the environment.
Store mercury switches in a suitable leak proof, closeable containers. A five
gallon plastic bucket with a lid may work.
Each container must be labeled "Mercury Switches for Recycling."
Be careful to keep the switches from breaking and releasing mercury into the
If breakage occurs, you must immediately take steps to contain and clean up
Take switches to a consolidation site or arrange with a transporter to take
Contact your county or state environmental office/ solid waste office for
services in your area.
Keep records of the mercury switches you have recycled, including copies of
invoices containing information on the date of shipment, number of switches,
location from where the switches are being shipped, and destination of
Manometers, Barometers, and Hydrometers
Description: Manometers and barometers are used for measuring air pressure.
Hydrometers are used to measure density of liquid.
How to Identify: All these devices will have a gauge for reading air pressure.
Pollution Prevention Options: The Replacements of mercury containing Manometers
are battery operated digital units and vacuum gauges. Battery operated digital units are
Safe Removal: To safely remove the manometer or barometer, remove the entire device
from the machine it is attached to.
Safe Disposal: Put the entire unit into an airtight, labeled container and ship it to a
mercury recycling plant.
Description: Sphygmomanometers are used to measure blood pressure.
How to Identify: Usually, they are installed on walls and placed on tables in hospitals.
Pollution Prevention Options: The replacement for mercury sphygmomanometers
includes electric vacuum gauges, aneroid monitors, and automated devices.
Recycling/Disposal: Develop a protocol for the preparation of mercury
sphygmomanometers for recycling or disposal that that is consistent with U.S.
Environmental Protection Agency, state and local regulations, and pertinent standards.
Contact your hazardous waste management coordinator for details about packaging,
labeling and transporting that are specific to your facility. A suggested protocol might
include the following instructions:
Place the sphygmomanometer in a clear plastic bag and seal the bag. Do not use a
red bag biohazard bag.
Mark the bag: "Contains Mercury."
Place the bag in a plastic basin to contain any spills during transport to the
designated hazardous waste collection point.
Description: Mercury zinc, carbon zinc, silver oxide, and zinc air contain mercury.
Mercury is used to protect cathode from oxidation.
Pollution Prevention Options: Most consumers dry-cell batteries contain no added
mercury. The best way to reduce mercury is recycling.
Description: Usually used as indoor lighting; the most common is the tube style, which
serves as overhead lighting in offices and business. A newer style is the compact globe
shape for a variety of home or office uses. Average life: 4 years.
How to Identify: Fluorescent lamps are located in offices and businesses. The most
common style is the long, thin tube used in overhead indoor lighting. Compact globe
style is also used in homes and offices.
Amount of Mercury: from less than 10 milligrams to 50 milligrams per tube, depending
on size and model. Almost lamps are from about 30 milligrams to 40 milligrams per tube.
Pollution prevention options: Fluorescent lamps are an excellent lighting choice because
they use up to 50% less energy than other lamps. This reduces the amount of mercury
produced at the power plant, where mercury is given off by coal and oil combustion.
Thus, even though incandescent bulbs contain no mercury, its inefficient energy use
result in more mercury being released to the environment. However, it is essential that
fluorescent lamps are disposed properly, so as not to allow the mercury to enter the
environment. The best reduce method is recycling.
A new type of long-life fluorescent lamp named ALTOTM has been developed which
contains such a small amount of mercury that it is no longer considered a hazardous
waste. The typical fluorescent lamps have a lot of "extra" mercury in it because mercury
loses its effectiveness over time due to physical and chemical reaction. This new lamp
has a buffering system that blocks these physical and chemical reactions so that the lamp
contains less than 10 mg of mercury. These lamps should still be recycled.
Safe removal: Caution should be taken to avoid lamp breakage. Breakage may result in
mercury released into the environment. Lamp recyclers also generally require that the
lamps arrive unbroken. The best way to protect them is putting old lamps into the boxes
from a lamp recycler.
Most bulb are removed in one of two ways:
With some bulbs, the technique to remove them is to push them in one
direction against a spring located in the socket and then they can be removed.
Other bulbs can simply be twisted to be removed, similar to incandescent
bulbs. The bulbs are very delicate and should be carefully removed and then
placed in boxes for disposal. Often, mercury recyclers rent or provide
cylindrical cardboard containers for fluorescent bulbs.
Safe Disposal: Store lamps in containers that prevent them from breaking, such as in
their original boxes or in boxes supplied by lamp recyclers.
Breakage of these lamps could result in mercury released.
Mark the lamp storage container as "Fluorescent Lamps for Recycling."
If lamps are accidentally broken, store them in a sealed container. Any spilled powder
should also be picked up and added to the sealed container.
Take lamps to a consolidation site or arrange for a lamp transporter to pick them up. To
find out the services available in your area, you should contact your county or state
environmental office or solid waste office.
To protect yourself from future liability, save the invoices that track your lamps and also
record the date of shipment, number of lamps, location from where the lamps are being
shipped, and destination of shipment.
Recycling protects human health and the environment and minimizes liability to the
High Intensity Discharge Lamps
Description: There are three types of HID bulbs: mercury vapor, high-pressure sodium,
and metal halide. All three contain mercury.
How to Identify: Most HID lamps are used in security, outdoor, and headlight of cars
Probable locations are parking lot light poles, the outside walls of buildings.
Amount of Mercury: Anywhere from 20 to 250 milligram are found in the average HID
Pollution Prevention Options: There are few alternatives for mercury containing HID
lamps. The lamps provide high intensity, energy-efficient light. For this reason, the lamps
should continue to be used. However, it is extremely important to properly recycle the
lamps to keep the mercury used out of the environment.
Safe Removal: Depending on the type of light, screwdrivers, nut drivers or wrenches
may be necessary. Usually the best way to remove the light is to remove the whole
lighting unit. The ballasts and batteries usually also contain PCB's and a toxic type of
battery acid that should also be handled properly. The average time to remove these lights
is around 90 seconds.
Safe Disposal: The lights should be placed in a box with some kind of packaging to
protect them from breaking. They should then be taken to a recycler prepared to handle
Element Mercury and Mercury Compounds
Description: Bottles or containers labeled as mercury or with the periodic symbol 'Hg'
can be found in a laboratory or dentist's office. Properties of elemental mercury are liquid
at room temperature, but with a metallic and shiny appearance, conductive, and highly
Caution: If a substance appears to be mercury, but is not labeled as such nor labeled as
another material, contain the material and have a laboratory test the material to conclude
what the substance is. When handling the unidentified material, take all safety
precautions in handling the material so as not to contact with the material and to
introduce the material into the environment. If a spill does occur, follow the proper safety
guidelines to clean up and contain the spilled mercury.
Storage of Elemental mercury: Elemental mercury should be stored in non-breakable,
labeled containers with the lids on tight. It should not be kept in rooms with carpet nor
rugs on the floor. In the event of a spill, carpet and rugs will absorb the mercury, thus
making it more difficult to clean up the spill. Workplaces that use mercury exposed to air
should be well ventilated. Mercury tends to vaporize and the most dangerous and likely
way to be contaminated by it is by inhalation in.
Pollution prevention Option:
Chemical Compounds --Substitutions
Mercury (II) Oxide --Copper catalyst
Mercury (II) chloride --Magnesium Chloride/Sulfuric Acid or Zinc
Formalin, Freeze drying
Mercury (II) sulfate --Silver Nitrate/Potassium/Chromium- (III) Sulfate
Mercury Nitrate (for corrosion of copper alloys) for antifungal use
(mercurochrome) --Ammonia/Copper Sulfate Neosporin, Mycin
Mercury Iodide--Phenate method
Sulfuric Acid (commercial grade: mercury as impurity)--Sulfuric acid from a
Zenker's Solution (Mixture of sodium sulfate, acetic acid, potassium
dichromate, and mercury (II) chloride) --Zinc Formalin
Spills of Elemental Mercury and Mercury Compounds
Small Spills: This procedure is appropriate for spills in the range of approximately
4-10 grams of mercury (2ml). The process should take an hour and the cost
1. Wear latex gloves and working form the perimeter of the spill push the mercury to
the center using the plastic scoop.
2. Spread the mercury suppression powder over the area as you clean it.
3. Collect the mercury using the suction apparatus.
4. After one hour collect the suppression powder and wash the surface with a
5. Store the contaminated gloves, collected mercury and the debris in a labeled
plastic bottle for later removal as hazardous waste.
6. Use a mercury indicator to detect any residual mercury.
Medium Spills: This procedure assumes that the room temperature is 25ºC or less
and that the spill is cleaned up within one day of the incident and that the surface is
smooth. This spill procedure uses a mercury spill kit from. This procedure is
appropriate for spills in the range of 10grams to 35grams.
1. Wear a tyvek suit with booties and a double pair of latex gloves.
2. Starting from the perimeter push the mercury towards the center using the plastic
3. Use the vacuum pump to collect any mercury trapped in the cracks of the floor
4. Spread the mercury suppression powder over the area you clean.
5. Collect the pooled mercury using the pump.
6. After one hour collect the mercury suppression powder and wash the surface with
7. Place all the contaminated material in a labeled container for later removal as
8. Use a detection tube or mercury indicator badge to determine if mercury vapors
Large Spills: Mercury spills involving more than a pound of mercury require
thorough evaluation before abatement. Since evaporation is a function of surface
area, the size of the mercury particles is critical in determining the hazard. The
surface type is also critical in spill evaluation. To avoid the problems associated with
mercury spills, locate your mercury item (for example: barometer) in the chemical
storage area in an area free of traffic. Do not store elemental mercury and avoid the
use of mercury barometers, solutions and compounds. For large spills we
recommend a professional evaluate the situation.
Spills Involving Mercury Compounds: Each mercury compound must be evaluated
individually as to the proper method of abatement. A small spill in the fume hood
could easily be abated with latex gloves and damp paper towels. The debris from
any mercury-containing spill must be disposed as hazardous waste. We recommend
avoiding the problem of mercury spills be avoiding the use of mercury and mercury
compounds. But if you do choose to use these compounds, you need to develop a
written standard operation procedure for abating spills and anticipate the cost of
disposal. For qualitative analysis mercurous salts are preferred over mercuric salts
due to their lower toxicity.
Details of work accomplished/Project result
Please see attached reports.
The following attached reports include whole buildings mercury chemical
compounds report, whole buildings fluorescent lamps report, all buildings mercury
items sum report, and whole buildings instruments report on campus.
Here is a summary for instruments containing mercury and mercury chemical
compounds on campus:
Conant Hall 4 12
Dairy Farm 3 9
Human Nutrition Center 4 12
Jackson Lab 16 48
James Hall 24 72
Kendall Hall 42 126
Kingman Farm Facility 2 6
Kingsbury Hall 34 298
Lee Farm Facility 2 6
Morse Hall 52 156
Parsons Hall 733 2208
Ritzman Hall 31 93
Perpetuity Hall 6 26
Rudman Hall 192 576
Spaulding Life Scien 28 84
Woodman Research Farm 20 60
Health Service Center 2 6
Total Amount 1195 3798g
Field House 1 3g
Perpetuity Hall 1 3g
Field House 2 4g
Kingsbury Hall 3 6g
Parsons Hall 2 4g
Dairy Farm 2
Parsons Hall 9
Parsons Hall 3
Kingsbury Hall 8
Parsons Hall 6
Health Service Center 17 340g
Amount of All Instruments on Campus 4484.16g
Mercury Chemical Compounds
Jackson Lab 255.1g
James Hall 253.4g
Kendall Hall 2756.8g
Kingsbury Hall 4536g
Morse Hall 1214.8g
Parsons Hall 46426.4g
Rudman Hall 3586.5g
Spauding Life Scien 1425.8g
Water Treatment B 238.4g
Total Amount 62421.73g
Amount of All Mercury Chemical Compounds 63421.73g
Number grams Hg
Demeritt Hall 1240 43.4g
Hamilton Hall 536 18.76
James Hall 1330 46.55
Kingsbury 2293 79.98
Morrill Hall 567 19.85
Morse Hall 2753 96.36
Thompson 36 1.26
Total Amount 8755 306.15
Recommendations for Future Efforts
We have researched some information about exchange program for thermometers
(http://p2pays.org/ref/01/00127.htm), and fluorescent
lamps(http://www.lighting.philips.com/nam/press/1997/08109g.shtml). Also we
have achieved some methods how to use free-mercury products to substitute
mercury-containing products. In the future, we will do our best to reduce and
eliminate mercury contamination and protect the health of human beings.