Air pollution is currently the world's largest single environmental health risk, according to the World Health Organization and a recent news release. Air quality in most cities worldwide that monitor air pollution fails to meet WHO guidelines.
The WHO reports that nearly seven million deaths were attributed to air pollution in 2012, or one in eight total global deaths.
However, new technologies are coming to the forefront allowing for greater opportunities to reduce pollution. One of them comes in the form of new building materials.
In 2013, the Manuel Gea González Hospital in Mexico City unveiled a façade made out of titanium dioxide coating designed specifically to reduce smog. The façade is made of modules called prosolve370e and designed by the Berlin-based Elegant Embellishments. The titanium dioxide is a pollution-fighting technology that is activated by ambient daylight as described on the product's website.
Hugo Destaillats, staff scientist with the Environmental Energy Technologies Division at the Lawrence Berkeley Lab in Berkeley, California, has done similar research on a laboratory scale and verified that titanium dioxide is effective in removing pollution.
"There are many studies by numerous groups around the world that also showed the same positive performance," Destaillats said.
In 2015, another building designed to fight pollution will be unveiled, this time in Milan, Italy, as part of the 2015 Milan Expo. Designed by the Italian architectural firm Nemesi & Partners, the "Palazzo Italia" encompasses 13,275 square meters (142,890 square feet) and six floors.
The outer façade, which is about 9,000 square meters,(96,875 square feet) will consist of 900 panels made from "i.active biodynamic" cement panels by Italcementi, an Italian multinational company that is the world's fifth largest cement producer.
"Palazzo Italia was designed in a sustainable manner, thanks to the contribution of photovoltaic glass and the photocatalytic properties of the new cement for the outer casing, obtained through the active substance TX Active patented by Italcementi," Nemesi & Partners said in a news release.
"In direct sunlight, the active principle contained in the material "captures" certain pollutants present in the air and converts them into inert salts, helping to purify the atmosphere from smog," according to Italcementi.
Destaillats called these buildings a "significant innovation" but this still needs to be demonstrated in the field.
"Laboratory tests are promising, but it's difficult to reproduce in small scale all the features of natural exposure," he said. "These new buildings will allow for real-world measurement and validation," he said.
Smog is basically a mixture of pollutants that is trapped in the lower part of the atmosphere, usually during an inversion and under light winds according to AccuWeather.com Expert Senior Forecaster Brett Anderson.
"A majority of smog is made up of ozone pollution from automobiles," Anderson said.
Climate can play a significant role in studying why pollution levels are higher in certain cities of the world as opposed to others.
"The role of climate is critical," Destaillats said. Cities [such as Los Angeles and Mexico City] with intense sun irradiation have a major problem with photochemical smog, induced precisely by sunlight."
"As the climate warms the demand for energy use [such as air conditioning, electricity] increases, which in turn leads to increased emissions and the potential for more smog," Anderson said. "Some studies also indicate that a warming climate will lead to more stagnant weather patterns."
"Stagnant areas of high pressure are the main weather pattern culprits for smog as they cause inversions and have little wind underneath the high pressure," Anderson said.
Destaillats added that precipitation can help with "cleaning" the air.
Anderson said smog is usually found in cities with a high concentration of automobile traffic as well as cities where the local topography can cause the polluted air to get trapped, citing Los Angeles as an example.
According to Anderson, the mountains to the north and east almost act like the lid on a bowl, keeping the dirty air in place over the city.
In the U.S., Anderson said he believed that pollution has decreased in the past few decades mainly due to increased regulations and the Clean Air Act.
"However, due to increasing automobiles, ozone pollution continues to be a growing problem for some cities," he said.
Recently, NASA released images to show how U.S. air quality has improved and that people living in major cities are breathing less nitrogen dioxide.