The human nose is the best odor-testing device available. Wave your hand across the water sample to make the odor come to you. A fishy odor may indicate the presence of too much dead algae. This condition may be caused by an unnatural amount of certain chemicals in the water (see phosphates and nitrates). A rotten egg smell would indicate the production of sulfur compounds (see pH). A sewage smell might indicate improperly treated sewage effluent (see phosphates and nitrates).

This list can help provide consistency in naming odors. Students should research the potential sources of these odors although this can sometimes be difficult. If the source can not be determined, be sure to consistently record it's presence for future reference.

Odor Such as odors of:
Aromatic (spicy) camphor, cloves, lavender, lemon
Balsamic (flowery) geranium, violet, vanilla
Chemical industrial wastes
Chlorinous chlorine
Hydrocarbon oil refinery
Medicinal phenol and iodine
sulfur hydrogen sulfide (rotten egg)
Disagreeable (pronounced, unpleasant)
Fishy dead fish
Septic stale sewage
Earthy damp earth
Peaty peat
Grassy crushed or mowed grass
Musty decomposing straw
Moldy damp cellar
Vegetable potatoes



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