Here in the state of Wisconsin including the City of Arcadia, clean water is essential to our economy and quality of life. Lakes and streams provide drinking water, recreational opportunities such as swimming and boating, and habitat for fish, wildlife and other aquatic species.
The Arcadia Wastewater Treatment Plant is required by the Wisconsin Department of Natural Resources (WDNR) to implement a Mercury Pollutant Minimization Program. This program is intended to reduce the mercury influent contributions from several community sectors to help achieve the Wisconsin Administrative Code NR 106.145 Water Quality Based Effluent Limit of 1.3 nanograms per liter (ng/l). For comparison purposes, one gram is roughly equal in weight to 1 small paper clip. Now divide that same paper clip into 1 billion tiny pieces, one of those billion pieces is a nanogram. Another example of a nanogram would be one blade of grass in two football fields.
The Arcadia Wastewater Treatment Plant plays a very important role in maintaining the water quality standards that are necessary to support a safe environment. Wastewater Treatment Facilities are capable of removing about 90% or more of the mercury entering their plant, but even this high removal rate is sometimes not sufficient for the facility's effluent (what is discharged to the river) to consistently meet the very low limit of 1.3 ng/l which is monitored by the WDNR. Mercury still finds it way into our municipal sewer systems from many sources in our city. The most cost effective way to reduce the amounts of mercury released into the environment is for each of us to do our part to keep mercury out of our city's sewer system.
What is Mercury?
Mercury is a highly toxic element (Hg on the periodic table) found both naturally and as an introduced contaminant in the environment. Mercury can be found in the water, soil and air. It also exists in several forms: metallic or elemental mercury, inorganic mercury compounds and organic mercury compounds. The toxic effects of mercury depend on its chemical form and the route of exposure.
Elemental or metallic mercury is a shiny, silver-white metal and is liquid at room temperature and if heated, it becomes a colorless, odorless gas. Elemental mercury is used in fluorescent light bulbs and some electrical switches. It can also be found in older thermometers and thermostats. When this form of mercury is dropped, elemental mercury breaks into smaller droplets which can go through small cracks or become attached to certain materials. At room temperature, exposed elemental mercury can evaporate to become an invisible, odorless toxic vapor.
Organic mercury compounds, such as methylmercury, are formed when mercury combines with carbon. Mercury in the atmosphere is eventually deposited on the earth's surface. It may be directly deposited from the air into bodies of water like lakes and streams or washed into those bodies by rain or snow. Naturally occurring bacteria in the water and soil, convert inorganic mercury into methylmercury, a highly toxic for of mercury. Small organisms take in the methylmercury as they feed. Small fish eat the small organisms, and when animals higher up on the food chain eat the smaller ones, they also take in the methylmercury. Fish that are higher in the food chain have much greater methylmercury concentrations in their tissues than fish that are lower on the food chain. People and fish-eating animals become exposed to mercury when they eat fish and shellfish that contain methylmercury. Should you stop eating fish and shellfish? No, to continue to enjoy the benefits of eating fish (they are important in an healthy diet), educate yourself in the types of fish that are low in mercury and limit your consumption of types of fish with typically higher levels of mercury. Check with your state and local governments to find out if there are any fish consumptions advisories in your area.
Inorganic mercury compounds take the form of mercury salts. They are generally white powder or crystals with the exception of mercuric sulfide (cinnabar) which is red.
Once mercury is released into the environment, it cycles between the soil, water and air because of it's ability to change form. Once mercury enters this cycle, it will remain in the environment for years as it accumulates. It cannot be removed, but it can be prevented from ever entering our environment.
Sources of Mercury
Sources of mercury vary because the element was used in the production of many products and energy. Many of the items that used to be manufactured with mercury have been removed from production and can no longer be purchased due to its health impacts. However, we may still be using some items that contain mercury in our homes and businesses and we need to be reminded to handle and dispose of them properly. When replacing a mercury product, please recycle the mercury and purchase a new, mercury-free product.
Some of the most commonly used mercury products:
| Mercury Source |
Alternatives |
| Barometers |
Digital/Aneriod |
| Dental mercury amalgam (fillings) |
Gold, composites |
| Fluorescent light bulbs |
There is not an alternative as energy-efficient at this time. Recyle after use |
| Lab thermometers |
Alcohol |
| Manometer |
Digital/Aneriod |
| Medical fever thermometers |
Digital |
| Paints |
Latex paint made after 1990 |
| Pesticides/fungicides |
Any product after 1995 |
| Sphygmomanometer (blood pressure cuff) |
Digital/Aneriod |
| Switches (lights, safety) |
Ball bearing or mechanical |
| Thermostats |
Electronic or snap-action |
| Button batteries |
Recycle after use |
Health Impacts of Mercury
Mercury can be extremely toxic if not handled or disposed of properly to wildlife and humans. Both short term and long term exposure to mercury can cause serious health problems for both people and wildlife. Almost everyone has at least trace amounts of mercury in their system indicating mercury's widespread presence in our environment. People and animals can be exposed to mercury in any of its forms under different circumstances. The factors that determine how severe the health effects are: the chemical form of mercury; the dose; the age of the person exposed; the duration of exposure; the route of exposure (inhalation, ingestion, skin contact, etc) and the health of the person/animal exposed.
Exposure to mercury can be dangerous for everyone but is particularly hazardous for pregnant women, babies and small children, which are more sensitive to the element and it's harmful effects. Once mercury enters the body of a person, it acts as a neurotoxin, interfering with the brain and nervous system. The nervous system is very sensitive to all forms of mercury. Symptoms include irritability, shyness, tremors, neuromuscular changes, skin rashes, changes in vision or hearing and memory problems. It can also cause other negative health impacts such as behavioral or reproductive problems. Children that are exposed to mercury may suffer from severe neurological disorders, developmental issues along with damage to the kidneys and digestive system.
Animals including domestic animals are also affected by exposure to mercury. In wildlife, fish-eating birds and mammals such as bald eagles, loons and river otters, have the greatest risk of mercury exposure because of their diet of mercury-laden fish. Symptoms in animals include a severe corrosive effect on the digestive system causing abdominal pain, diarrhea, tremors, blindness, deafness, convulsions, abnormal movement and paralysis.
What Can You Do?
Recycle mercury containing items to keep them from entering our city's sewer system by bringing your mercury containing items to a hazardous waste or authorized mercury collection site. All mercury and mercury-containing items should be recycled. Never pour mercury down the a drain or sewer, flush down a toilet, or throw in the trash. Whenever possible, choose mercury free or low mercury containing products for your home or business. Educate your family on the dangers of mercury and what to do in case of a spill.
Mercury Spill and Clean Ups
When mercury is spilled, it shatters into tiny beads and spreads in many directions. These tiny droplets can accumulate in the smallest places. The droplets emit toxic, odorless vapors, which can be very dangerous when inhaled by people or pets.
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Report all mercury spills immediately by calling the 24-hour, toll free hotline at 1-800-943-0003.
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Possible mercury poisoning? Call the toll free poison hotline at 1-800-222-1222.
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Any object that touches mercury will become contaminated.
To learn how to prevent, clean up and properly dispose of mercury, see http://www.epa.gov/mercury/spills/index.htm#thermometer.
Source: WI Department of Natural Resources
US Environmental Protection Agency