Students observe brine shrimp as they
are affected by household cleaners. Students develop
an observation scale, collect and analyze data.
Students will be able to:-
1. make observations about a living organism
2. recognize that household products impact their environment
3. Compare the relative toxicity of chemicals by observing the relationship
of dose to response on shrimp.
National Science Education Standards
C- The Interdependence of Organisms
Human beings live within the worlds ecosystems. Increasingly, humans modify
ecosystems as a result of population growth, technology, and consumption. Human
destruction of habitats through direct harvesting, pollution, atmospheric changes,
and other factors is threatening global stability, and if not addressed, ecosystems
will be irreversibly affected.
W-P1. Use transitional devices: varied sentence structures; the active voice;
parallel structures; supporting details, phrases and clauses; correct
spelling, punctuation, capitalization, grammar and usage to sharpen the
focus and clarify the meaning of
Many people are not aware of the potential harmful effects of
household chemicals and pesticides. Toxicity is the ability of a chemical to
cause injury or death.
This activity allows students to quantitatively measure the toxic effects of
common household chemicals and/or pesticides on brine shrimp (sea monkeys).
Students will dose a group of brine shrimp with specific amounts of test chemicals
and notice how the chemicals affect their ability to swim. At some point, enough
chemical will be added so that some of the shrimp are killed. LD50 is the term
for "lethal dose at which 50% of the animals die". This measurement
is used by the Environmental Protection Agency to measure the acute toxicity
pesticides, that is, how much in a single dose will cause injury or death.
A small number for the LD50 means a small amount of the chemical is acutely
toxic. In this experiment, students will be able to compare the relative toxicity
of chemicals chosen by observing the relationship of dose to effect on the