Search results
Results From The WOW.Com Content Network
Ground-level ozone (O 3), also known as surface-level ozone and tropospheric ozone, is a trace gas in the troposphere (the lowest level of the Earth's atmosphere), with an average concentration of 20–30 parts per billion by volume (ppbv), with close to 100 ppbv in polluted areas.
The ozone at ground level is primarily from fossil fuel precursors, but methane is a natural precursor, and the very low natural background level of ozone at ground level is considered safe. This section examines the health impacts of fossil fuel burning, which raises ground level ozone far above background levels.
Schematic drawing, causes and effects of air pollution: (1) greenhouse effect, (2) particulate contamination, (3) increased UV radiation, (4) acid rain, (5) increased ground-level ozone concentration, (6) increased levels of nitrogen oxides. An air pollutant is a material in the air that can have many effects on humans and the ecosystem. [61]
Lighter Side. Medicare. News
Smog is a serious problem in many cities and continues to harm human health. [30] [31] Ground-level ozone, sulfur dioxide, nitrogen dioxide and carbon monoxide are especially harmful for senior citizens, children, and people with heart and lung conditions such as emphysema, bronchitis, and asthma. [14]
Ozone depletion would magnify all of the effects of UV on human health, both positive (including production of vitamin D) and negative (including sunburn, skin cancer, and cataracts). In addition, increased surface UV leads to increased tropospheric ozone, which is a health risk to humans. [61]
Ozone was originally found to be damaging to grapes in the 1950s. The US EPA set "oxidants" standards in 1971, which included ozone. These standards were created to reduce agricultural impacts and other related damages. Like lead, ozone requires a reexamination of new findings of health and vegetation effects periodically.
Sulfate pollution also has a complex relationship with NOx pollution and ozone, reducing the also harmful ground-level ozone, yet capable of damaging the stratospheric ozone layer as well. [122] Stratospheric sulfates from volcanic emissions cause transient cooling; the purple line showing sustained cooling is from tropospheric sulfate pollution.