Pollutant

Pollutants can be categorized in a variety of different ways. For example, it is sometimes useful to distinguish between stock pollutants and fund pollutants. Another way is to group them together according to more specific properties, such as organic, particulate, pharmaceutical, et cetera. The environment has some capacity to absorb many discharges without measurable harm, and this is called “assimilative capacity (or absorptive capacity); a pollutant actually causes pollution when the assimilative capacity is exceeded. Stock pollutants Pollutants, towards which the environment has low absorptive capacity are called stock pollutants. Scientists have officially deemed that the planetary boundaries safe chemical pollutant levels (novel entities) have been surpassed. • Particulate matter (PM) • Persistent organic pollutants (POPs) • Polycyclic aromatic hydrocarbons (PAHs) • Volatile organic compounds (VOCs) Light pollutant Light pollution is the impact that anthropogenic light has on the visibility of the night sky. It also encompasses ecological light pollution which describes the effect of artificial light on individual organisms and on the structure of ecosystems as a whole. with light pollution in the background ==Zones of influence==

Pollutants can also be defined by their zones of influence, both horizontally and vertically. Horizontal zone The horizontal zone refers to the area that is damaged by a pollutant. Local pollutants cause damage near the emission source. Regional pollutants cause damage further from the emission source. Vertical zone The vertical zone refers to whether the damage is ground-level or atmospheric. Surface pollutants cause damage by accumulating near the Earth's surface. Global pollutants cause damage by concentrating on the [atmosphere]. == Measuring concentration ==

International Pollutants can cross international borders and therefore international regulations are needed for their control. The Stockholm Convention on Persistent Organic Pollutants, which entered into force in 2004, is an international legally binding agreement for the control of persistent organic pollutants. Pollutant Release and Transfer Registers (PRTR) are systems to collect and disseminate information on environmental releases and transfers of toxic chemicals from industrial and other facilities. European Union The European Pollutant Emission Register is a type of PRTR providing access to information on the annual emissions of industrial facilities in the Member States of the European Union, as well as Norway. United States Clean Air Act standards. Under the Clean Air Act, the National Ambient Air Quality Standards (NAAQS) are developed by the Environmental Protection Agency (EPA) for six common air pollutants, also called "criteria pollutants": particulates; smog and ground-level ozone; carbon monoxide; sulfur oxides; nitrogen oxides; and lead. The National Emissions Standards for Hazardous Air Pollutants are additional emission standards that are set by EPA for toxic air pollutants. Clean Water Act standards. Under the Clean Water Act, EPA promulgated national standards for municipal sewage treatment plants, also called publicly owned treatment works, in the Secondary Treatment Regulation. National standards for industrial dischargers are called Effluent guidelines (for existing sources) and New Source Performance Standards, and currently cover over 50 industrial categories. In addition, the Act requires states to publish water quality standards for individual water bodies to provide additional protection where the national standards are insufficient. RCRA standards. The Resource Conservation and Recovery Act (RCRA) regulates the management, transport and disposal of municipal solid waste, hazardous waste and underground storage tanks. == See also ==