Search results
Results from the WOW.Com Content Network
Pollution is the introduction of contaminants into the natural environment that cause harm. [1] Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants.
This list gives those most commonly encountered with Latin script. For a far more comprehensive list of symbols and signs, see List of Unicode characters . For other languages and symbol sets (especially in mathematics and science), see below .
Air pollution can occur naturally or be caused by human activities. [4] Air pollution causes around 7 or 8 million deaths each year. [5] [6] It is a significant risk factor for a number of pollution-related diseases, including heart disease, stroke, chronic obstructive pulmonary disease (COPD), asthma and lung cancer.
noise pollution (environmental noise) - displeasing human or machine created sound that disrupts the activity or happiness of human or animal life. nonpoint source pollution - water pollution affecting a water body from diffuse sources, rather than a point source which discharges to a water body at a single location.
In contrast, a character entity reference refers to a character by the name of an entity which has the desired character as its replacement text. The entity must either be predefined (built into the markup language) or explicitly declared in a Document Type Definition (DTD). The format is the same as for any entity reference: &name;
A pollutant or novel entity [1] is a substance or energy introduced into the environment that has undesired effect, or adversely affects the usefulness of a resource. These can be both naturally forming (i.e. minerals or extracted compounds like oil) or anthropogenic in origin (i.e. manufactured materials or byproducts).
List of mathematical constants (typically letters and compound symbols) Glossary of mathematical symbols; List of physical constants (typically letters and compound symbols) List of common physics notations (typically letters used as variable names in equations) Rod of Asclepius / Caduceus as a symbol of medicine
A practical definition of water pollution is: "Water pollution is the addition of substances or energy forms that directly or indirectly alter the nature of the water body in such a manner that negatively affects its legitimate uses." [1]: 6 Water is typically referred to as polluted when it is impaired by anthropogenic contaminants.