background concentration teriminin İngilizce İngilizce sözlükte anlamı
The concentration of any substance which would normally be found in an area This amount is used as a basis of comparison in identifying contamination levels
The pollutant levels that are found throughout the continental United States even in "clean air locations," areas where no man-made air toxic emissions would be expected They are a result of past emissions of persistent pollutants, long-range transport of recent emissions, and widespread man-made sources
A concentration of a substance in a particular environment that is indicative of minimal influence by human (anthropogenic) sources