Mercury -Biomagnification Math

Name:______

Date:______

What is Bioaccumulation/Biomagnification/Bioamplification?

/ Let’s look at our food chain to see how biomagnification works. Let's say for example that each piece of plant material has one microscopic drop of methylmercury. One insect eats 25 pieces of plant material, that would mean that each insect would have ______microscopic drops of methylmercury in its body.
One small fish needs 10 insects to live, if each insect has 25 microscopic drops of methylmercury in its body, then one fish would have ______microscopic drops of methylmercury.

One big fish eats 5 small fish to live. Each small fish has ______microscopic drops of methylmercury in its body, therefore, one big fish would collect a total of ______microscopic drops of methylmercury in its body.

What about you and me? Lets say we eat 1 big fish a day for 3 days. If each big fish has ______drops of methylmercury in its body then we would collect a total of ______drops of methylmercury in our body over the 3 days. This is how biomagnification works!

Now let's say that methylmercury makes living things sick. The more methylmercury in the living organism, the more sick it would get. From our example above, which organism will be most affected by the toxin methylmercury? ______

Mercury

The Mystery of Methylmercury

Mercury is a silvery metal (like aluminium) that is in a liquid form (like silvery water) at room temperature. If you drop mercury onto a table it will stay in the shape of a ball rather than becoming flat like water. Mercury can some times be seen inside a thermometer. Mercury is a toxin which slowly evaporates. If you spill mercury or keep it somewhere loose (out of a thermometer) it can contaminate the air you breathe. If you throw a mercury thermometer into the garbage, it will end up in our landfills (garbage dumps) where the mercury can escape and end up in the soil or water.

In the lakes and rivers, bacteria change mercury to a more poisonous form called methylmercury. Methylmercury will work its way up the food chain into fish. As you now know from the biomagnification math, once in the food chain the levels of a toxin like methylmercury keep collecting in greater and greater amounts.
Children are more sensitive to mercury poisoning than adults and more likely to be seriously affected from exposure to mercury vapour, (the gas produced from evaporated mercury). Mercury poisoning can affect the brain, spinal cord, kidneys and liver.
More recently, people have become aware of the problems with using mercury and in many cases alternative technologies have been developed. Also, people are making sure to properly dispose of mercury and mercury related products /
Source: Wisconsin Department of Natural Resources and the Pollution Prevention Partnership; "Mercury: In Your Community and the Environment". PUB-CE-239 98

Today, mercury is used in some household products and in some industries. Power plants that produce electricity by burning coal, release mercury into the air. While some manufacturers, hospitals, dental offices and schools produce waste that contains mercury. Mercury has many properties. Because mercury is a good conductor of electricity, which means electrical currents move through it easily, it is used it some electrical equipment. Many types of lights contain mercury, including fluorescent and neon lights.

Questions:

  1. How does mercury get into ecosystems?
  1. What form of mercury is harmful to living things?
  1. What are the effects of mercury poisoning on people?
  1. Explain why animals at the top of the food chain have the highest concentration of the toxin.