Air pollution caused by burning rubbish much higher than previously thought, research finds

The amount of air pollution caused by the unregulated burning of rubbish is a lot higher than previously suggested, researchers have said.

The researchers from the National Center for Atmospheric Research said that 1.1 billion tons, which equals about 41%, of the total waste generated worldwide is disposed of through unregulated burning – each year.

The work showed that in China 22% of the larger type of air pollution particles came from burning garbage.

Air pollution is monitored on two difference scales, which relate to the diameter of particles in the air.

Fine particles are produced by all types of combustion including the use of cars, power plants, wood burning and some industrial processes.

Coarse dust particles are created from crushing or grinding operations and dust stirred by vehicles travelling on roads.

They identified China, India, Brazil, Mexico, Pakistan, and Turkey, as the countries that generated the most emissions from burning trash.

The researchers put most of this down to the rapid expansion of developing countries, whether there are also fewer trans disposal facilities landfills and incinerators.


The researchers found that as much as 29% percent of global emissions of small particulates created come from fires.

This is as well as 10% or mercury and 40% of a group of gases known as polycyclic aromatic hydrocarbons (PAHs). These have all been said to have dangerous health impacts.

“Air pollution across much of the globe is significantly underestimated because no one is tracking open-fire burning of trash,” said scientist Christine Wiedinmyer, lead author of the new study.

“The uncontrolled burning of trash is a major source of pollutants, and it’s one that should receive more attention.”

Estimated annual emissions of carbon monoxide (CO, Gg yr−1) from the open combustion of waste at residences and dumps.

Estimated annual emissions of carbon monoxide (CO, Gg yr−1) from the open combustion of waste at residences and dumps.

However Wiedinmyer said that the actual emissions could be higher or lower than the team’s estimates by a factor of two.

This is partly because it is incredibly difficult to measure and is unregulated.

She said: “This study was a first step to put some bounds on the magnitude of this issue.

“The next step is to look at what happens when these pollutants are emitted into the atmosphere—where are they being transported and which populations are being most affected.”

Image two courtesy of NCAR

3D Implants: Printing personalised medical beads to treat illness

Researchers have created customisable antibiotic implants that can be made on consumer-grade 3D printers.

The technology could lead to personalised medical treatments that can be easily made for individual patients.

The custom bead-shaped medical implants were created by a team from Louisiana Tech University who say they can target drug delivery using their creation.

The beads, which may contain cancer-fighting compounds or any other antibacterial substance, would be broken down by the body over time.

The major advantage of their work is the ability to create the beads on a 3D printer that could be purchased by anyone.

Jeffery Weisman, a doctoral student in Louisiana Tech’s biomedical engineering programme, said their work was accessible to a wide number of people.

He said: “One of the greatest benefits of this technology is that it can be done using any consumer printer and can be used anywhere in the world.”


Weisman said that his team’s work used bioplastics that can be re-absorbed by the body.

Current beads, which can be made for individual patients, have to be hand-made, cannot be fully broken down by the body and also require surgery to be removed.

He said: “After identifying the usefulness of the 3D printers, we realised there was an opportunity for rapid prototyping using this fabrication method.

“Through the addition of nanoparticles and /or other additives, this technology becomes much more viable using a common 3D printing material that is already biocompatible.

“The material can be loaded with antibiotics or other medicinal compounds, and the implant can be naturally broken down by the body over time.”


Their work brings down the scale and cost of existing technologies that lead to personalised medical treatments.

“Currently, embedding of additives in plastic requires industrial-scale facilities to ensure proper dispersion throughout the extruded plastic,” said Dr David K. Mills who led the work.

“Our method enables dispersion on a tabletop scale, allowing researchers to easily customise additives to the desired levels.

“There are not even any industrial processes for antibiotics or special drug delivery as injection molding currently focuses more on colourants and cosmetic properties.”

Image one courtesy of Louisiana Tech University