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Nature's Response to Land Contamination
Published in Daniel T. Rogers, Environmental Compliance Handbook, 2023
Ozone is a gas occurring in Earth’s upper atmosphere and at ground level. Ozone in the upper atmosphere is greatly beneficial to life on Earth because it filters UV radiation, but ozone occurring at ground level is considered an air pollutant (USEPA 2021a). Ground-level ozone is not emitted directly into the air-it is created by chemical reactions between oxides of nitrogen and VOCs in the presence of sunlight. Emissions from automobile exhaust, gasoline vapors, chemical solvents, electrical generating facilities, and some factories trigger the production of ground-level ozone (USEPA 2009b). This variety of ozone is a concern in urban regions of the United States during the summer, because strong sunlight and hot weather can generate higher levels (USEPA 2009b). Since the Clean Air Act of 1990, atmospheric ozone concentration in the United States has declined 25% (USEPA 2021a). Better control of stationary and mobile sources of air pollution such as automobile exhaust is behind this improvement (USEPA 2021a).
Photochemical Smog
Published in Stanley E. Manahan, Environmental Chemistry, 2022
The harmful effects of smog occur mainly in the areas of (1) human health and comfort, (2) damage to materials, (3) effects on the atmosphere, and (4) toxicity to plants. The exact degree to which exposure to smog affects human health is not known, although substantial adverse effects are suspected. Pungent-smelling, smog-produced ozone is known to be toxic. Ozone at 0.15 ppm causes coughing, wheezing, bronchial constriction, and irritation to the respiratory mucous system in healthy, exercising individuals. In March 2008, the US Environmental Protection Agency released a revised eight-hour national ambient air quality standard for ground-level ozone of 0.075 ppm based on likely health effects of this pollutant. At the same time, the EPA also revised the secondary standard for ground-level ozone to the same 0.075 ppm level. In 2015, the EPA proposed lowering the ozone standard only slightly to 0.070 ppm although the agency's scientific panel had earlier proposed a standard of 0.060 ppm. The secondary standard is based on evidence of ozone damage to plants, trees, and crops during the growing season. In addition to ozone, oxidant peroxyacyl nitrates and aldehydes found in smog are eye irritants.
Air pollutants and their sources
Published in John K. Pearson, Richard G. Derwent, Air Pollution and Climate Change, 2022
John K. Pearson, Richard G. Derwent
At ground level, ozone is a secondary pollutant formed by sunlight-driven chemical reactions involving VOCs and NOx precursors and is transported across international boundaries by wind fields. As such, it is being addressed by all countries, which continue to reduce these two main precursor pollutants. Both chemical reactivity and meteorology are the key factors in ground-level ozone formation and mathematical models are used to predict the optimum strategy for ozone reduction in any region, as seen in Chapters 5 and 7. It is interesting to note that isoprene is one of the most reactive VOCs in ozone formation and is a major component of natural biogenic VOC emissions from trees. Strategies to control ozone formation have to take into account both man-made and biogenic VOCs in any particular region, together with NOx emissions. It has become recognised that the formation of ozone across Europe and large parts of North America are now NOx-limited and, consequently, further NOx emission reductions will have the greater impact on reducing ozone levels compared with VOC reductions.
Unexpected reduction in ozone levels in a mid-size city during COVID-19 lockdown
Published in International Journal of Environmental Health Research, 2022
Ronan Adler Tavella, Caroline Lopes Feijo Fernandes, Julia Oliveira Penteado, Rodrigo De Lima Brum, Paula Florencio Ramires, Laiz Coutelle Honscha, Marina Dos Santos, Lisiane Martins Volcão, Ana Luíza Muccillo-Baisch, Flavio Manoel Rodrigues Da Silva Júnior
Among the air pollutants capable of causing damage to human health, ground-level ozone (O3) is considered one of the most harmful (World Health Organization 2013). This pollutant is associated with negative effects on the respiratory and cardiovascular systems (Valavanidis et al. 2013; Sicardi et al. 2016; Kilburg-Basnyat et al. 2018). Tropospheric O3 formation occurs when nitrogen oxides (NOx) and volatile organic compounds (VOCs) react in the atmosphere in the presence of sunlight. The latter can be released into the environment by anthropogenic actions, such as through the burning of fossil fuels or fuel volatilization (Zhang et al. 2019). The measurement of O3 concentration in the atmosphere can be performed using active methods, which usually have high maintenance costs, passive methods or satellites. In this regard, passive methods stand out because they allow a better simultaneous assessment of several sites and have low costs and quick responses, while other methods are not as effective in this type of evaluation.
Terpene exhaust emissions and impact ozone modeling from cannabis plants at commercial indoor cultivation facilities in Colorado
Published in Journal of the Air & Waste Management Association, 2022
Kaitlin Urso, Alicia Frazier, Sara Heald, Andrey Khlystov
Ozone is one of six criteria pollutants that the U.S. Environmental Protection Agency (EPA) regulates (EPA 2021). EPA has promulgated National Ambient Air Quality Standards (NAAQS) to help protect against the adverse health effects of ground-level ozone (Clean Air Act 1990). Adverse health effects of ozone include shortness of breath, asthma attacks, increased risk of respiratory infections and pulmonary inflammation, and even premature mortality (EPA 2015). The DM/NFR NAA is currently in violation of two ozone NAAQS: The 70 parts per billion (ppb) ozone NAAQS promulgated in 2015; andThe 75 ppb ozone NAAQS promulgated in 2008.
Air quality and source apportionment modeling of year 2017 ozone episodes in Albuquerque/Bernalillo County, New Mexico
Published in Journal of the Air & Waste Management Association, 2020
Kenneth Craig, Garnet Erdakos, Shih Ying Chang, Lynn Baringer
Tropospheric ozone is a secondary pollutant formed from precursor emissions of oxides of nitrogen (NOx) and volatile organic compounds (VOC) in the presence of sunlight (Seinfeld and Pandis 1998). Ground-level ozone has harmful effects on human health and reduces the productivity of vegetation and crops (Ainsworth et al. 2012; Capps et al. 2016; Lefohn et al. 2018). Precursor emissions contributing to the formation of ozone can be of anthropogenic (human-made), biogenic, or geogenic origin. Significant sources of anthropogenic ozone precursor emissions include fossil fuel combustion, agriculture, biomass burning, oil and gas (O&G) production, and other industrial processes. Background ozone, which is not directly controllable under U.S. regulatory policy, results from long-range transport of ozone and its precursors from overseas, and from non-anthropogenic sources such as stratospheric ozone intrusions (Langford et al. 2015; Lin et al. 2012, 2017), NOx emissions from soil (Almaraz et al. 2018; Romer et al. 2018) and lightning (Allen et al. 2012), biogenic VOC emissions (Pierce et al. 1998; Roselle 1994), and biomass burning (Lu et al. 2016). Background ozone combines with regionally transported and local emissions to impact ozone concentrations in urban areas.