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exert a considerable impact on global warming, because it is a key air pollutant and greenhouse gas, and; impact the production of surface level ozone (contributing again to climate change). As a result, photochemical smog pollution at the earth's surface, as well as stratospheric ozone depletion, have received a lot of attention in recent years.
Ozone is a toxic substance, [42] [43] commonly found or generated in human environments (aircraft cabins, offices with photocopiers, laser printers, sterilizers...) and its catalytic decomposition is very important to reduce pollution. This type of decomposition is the most widely used, especially with solid catalysts, and it has many ...
Ozone-oxygen cycle in the ozone layer. The photochemical mechanisms that give rise to the ozone layer were discovered by the British physicist Sydney Chapman in 1930. Ozone in the Earth's stratosphere is created by ultraviolet light striking ordinary oxygen molecules containing two oxygen atoms (O 2), splitting them into individual oxygen atoms (atomic oxygen); the atomic oxygen then combines ...
A 2002 study found that "Each 10 μg/m 3 elevation in fine particulate air pollution was associated with approximately a 4%, 6% and 8% increased risk of all-cause, cardiopulmonary, and lung cancer mortality, respectively."
Growing evidence that air pollution—even when experienced at very low levels—hurts human health, led the WHO to revise its guideline (from 10 μg/m 3 to 5 μg/m 3) for what it considers a safe level of exposure of particulate pollution, bringing most of the world—97.3 percent of the global population—into the unsafe zone.
These sections require the EPA "(1) to list widespread air pollutants that reasonably may be expected to endanger public health or welfare; (2) to issue air quality criteria for them that assess the latest available scientific information on nature and effects of ambient exposure to them; (3) to set primary NAAQS to protect human health with ...
Ozone absorbs strongly in the ultraviolet and in the stratosphere functions as a shield for the biosphere against mutagenic and other damaging effects of solar UV radiation (see ozone layer). [5] Tropospheric ozone is formed near the Earth's surface by the photochemical disintegration of nitrogen dioxide in the exhaust of automobiles. [10]
Already by 1994 the legal debates about respective regulation regimes on climate change, ozone depletion and air pollution were being dubbed "monumental" and a combined synopsis provided. [ 2 ] There are some parallels between atmospheric chemistry and anthropogenic emissions in the discussions which have taken place and the regulatory attempts ...