Air pollution occurs when chemical, physical or biological substances alter the natural characteristics of the atmosphere, potentially leading to respiratory and other diseases that can be lethal.
The International Agency for Research on Cancer (IARC) at the World Health Organization classifies particulate matter, the main component of air pollution, as carcinogenic and published a study in 2013 definitively linking air pollution and lung cancer.
Industrial cities and densely populated metropolises are home to many sources of air pollution or otherwise fail to counter natural and manmade pollution sources, creating public planning risk scenarios that require mitigation. Of concern to health officials in urban areas are: large open grounds without any trees or grass and that may also lack protection against erosion; motorization, including exhaust and particulates from the residue of tire friction against asphalt; and winterization of roadways, commonly with sands and other reagents. Rural living conditions in the developing world can present uniquely challenging pollutants because reducing the pollutants would require cultural adaptations. For example, the use of biomass for fuel and home construction as well as poor sanitation in highly travel roadways generates air pollution.
*PM10 is used to describe particles of 10 micrometers or less and PM2.5 represents particles less than 2.5 micrometers in aerodynamic diameter.
The worst drought to affect South Africa in the last century is further damaging the economic strength of the county's sugar sector. According to the United States Department of Agriculture, South Africa was expected to harvest 1.61 million metric tons of sugar during the 2016/2017 marketing year, a decrease of 5.5 percent from the previous marketing year and the lowest marketed-yield since 1995. Sugar producers are already grappling with competition from cheap imports, forcing some mills to remain closed and reducing employment in the sector.Note: Precipitation amounts less than 0.5 mm have been replaced with "0" values.
The current state standards for drinking water in the United States do not take into account the harmful impurities that have appeared in it, such as metals and chemicals. "Today, thousands of toxic substances, organic and inorganic, enter the house of every American through the water supply system", - summarizes Philip Hart, a Senator from Michigan. That's why in the US bottles of spring water are sold in each grocery store, and all machines have long been accustomed to the machines that sell it.
Note: amounts less than 0.5 mm replaced with "0"