Science is
a collection of opinions and beliefs
a process to use to investigate the natural world
experiments that prove complicated things about the world
all the laws that govern the universe

poor water quality affects most estuarine organisms, including commercially important fish and shellfish. the pollutants that have the greatest impact on the health of estuaries include toxic substances like chemicals and heavy metals, nutrient pollution (or eutrophication), and pathogens such as bacteria or viruses.