Apparently pollutants are being concentrated in the small aquatic insects that are the food of the hungry and quickly growing salmon. It is not yet known exactly which chemicals or environmental factors are responsible. But in light of the current struggle to save dwindling populations of salmon in many West Coast rivers, fishery scientists are looking seriously at the role of water pollution in salmon decline. Many of the hazardous chemicals in the water are exotic combinations that emerge from factory pipes. While households play a comparatively minor role in adding pollutants to our waters, even small amounts can contribute to water quality problems and are highly toxic to fish and the aquatic insects on which they prey.
Substances washing down the drain can affect water quality in other ways too.
Everyone can contribute to the effort to protect salmon and other fish populations by taking great care about what goes down the drain. And everyone can make sure that household pesticides and other poisons are never flushed down the drain and eventually into the river. Store wastes and empty containers in a covered repository. Try to avoid pesticide use in the first place by sealing all points of entry, removing sources of food and water for insects and rodents, treating pets for fleas with soapy water and a flea comb, attracting slugs with beer, and attacking ants with boiling water. Get acquainted with the virtues of vinegar, baking soda, lemon juice and borax.