As the world’s population continues to grow, so does its waste. According to the United Nations’ “World Population Prospects,” there is a worldwide trend for improvements in life expectancy accompanied by an increase in concerns about how much waste is being produced and where it all goes. With no clean solution available, scientists have turned to nanotechnologies in their search for environmentally-friendly solutions. Nowadays, these technologies are not just limited to anti-aging skin care creams; they’ve been utilized globally and are working.
The United States alone produces 27 million tons of hazardous material annually and more than 15 billion pounds of toxic waste each day. While the Environmental Protection Agency (EPA) has set standards for disposing of all this waste, it is often shipped to developing countries where there are fewer occupational and environmental protections. In other words, hazardous materials are being dumped in developing countries, where they remain and contaminate the soil and groundwater for generations. Needless to say, despite US efforts to ensure that these sites are properly rehabilitated, many still present a serious health risk.
Furthermore, according to “Waste Management and Technology,” poor management of hazardous waste leads to pollution of land and water systems with toxic chemicals that threaten human health as well as environmental stability throughout developing nations. The end result is global contamination of water supplies by toxic heavy metals and other contaminants.
So, how can nanotechnologies help us solve this global dilemma? Well, they’ve already been used to remediate land polluted with toxic waste. According to “The Nanotechnology Revolution,” magnetic nanoparticles were coated onto sewage sludge and turned into magnetite. This was then used to remediate chromium pollution in California’s groundwater and soil. Over time, the sludge lost its toxicity and became inert after being treated by the nano-magnetites.
Researchers have also been developing a technology that protects people from exposure to harmful chemicals used in consumer goods like cosmetics and personal care products. Nanoscale silver particles can help eliminate bacteria such as E.coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli.
These are just a few examples of nanotechnology’s potential to help us clean up toxic waste. Nanotechnologies have already made significant progress in medical applications, such as improved prostheses for artificial limbs and better ways to deliver vaccines and medicines. They even have the potential to make the environment cleaner and safer by helping to clean up all types of waste.
What is nano encapsulation?
One specific application of nanotechnology that has been making headway in the field of cleanup operations is nano-encapsulation. This entails using nanomaterials to produce little containers that hold a significant amount of toxic waste and then pumping them out of the site into specialized disposal facilities. The containers are then filled with different types of waste and disposed of, again by pumping.
Depending on the type of chemical contained in the waste, the amount of encapsulation needed can vary greatly. For example, toxic sludge from a copper smelter contains concentrated levels of arsenic and other heavy metals, which makes its removal a significant problem. In order to remove it safely, gallons of different chemicals are pumped into the containers that make up this toxic sludge and then sent to a special facility in order to be slaked out by being allowed to evaporate over a period of time. After nearly all the toxic chemicals have evaporated, the remaining solids are collected and disposed of according to state regulations.
Since the beginning of this project, the amount of toxic waste removed has decreased by about 80%. This decrease can be attributed to the removal of harmful emissions from smelters and the fact that less toxic chemicals are now being mechanically transported to special facilities for disposal. Other examples include the removal of heavy metals from spent lead batteries.
Even though their waste contains toxic materials like lead and cadmium, it is not harmful when properly disposed of in a way that does not allow its residual solids to mix with other substances. Another key application of nanotechnologies in the field of toxic waste removal is the use of nanoparticles as catalysts for safer chemical reactions. In these reactions, hazardous chemicals are removed or destroyed by nanomaterials that are less harmful to the environment and humans.
For example, in an effort to help solve a growing public health problem, scientific research is currently being conducted on plume remediation using nanoparticles capable of removing nitrates and thereby reducing their bioavailability to the environment. This can eliminate labile gases like ammonia and hydrogen sulfide, which can be toxic if inhaled over a long period of time.
Nano particles in automobiles
In addition, nanoparticles can also be used to remove toxic chemicals like dioxins and polycyclic aromatic hydrocarbons found in the exhaust of automobiles, biofuel boilers, and other industrial processes that contribute to environmental pollution.
Nano particles to clean oil spills
The use of nanoparticles in cleaning up hazardous waste sites is also an important application of nanotechnology in the field of science. As an example, nanoparticles may be used to dissolve the oil that spills into the water and thereby help clean up offshore drilling sites.
When these nanoparticles are released onto the surface of the water, they can absorb oil that has been spilled and break it down into smaller particles so as to allow this water to be cleaned. Nanoparticles released into a body of water have been shown to have similar effects on removing pollutants from a river that contains toxic sludge and heavy metals by breaking them down for disposal.
According to the EPA, toxic substances can build up over time in specific areas due to their close proximity and exposure to these chemicals. These hazardous locations, known as “Superfund sites” by the EPA, may require extensive cleanup efforts that can include depolluting soil or groundwater and allowing them to dissipate over time.
The result of these cases is often a need for remediation to avoid any further contamination and help control runoff that may be harmful if it accumulates into public water supplies. In certain cases, this can necessitate the use of nanotechnologies that help remove hazardous waste from areas where it may have been buried after having been dumped there by industrial processes or other operations.
What is bio remediation?
According to the EPA, scientists are now using nanotechnologies to develop innovative measures for the cleanup of hazardous sites. One specific example is the use of nanomaterials that can serve as “bio-remediation” agents and help break up hazardous compounds that have been buried in soil or groundwater.
Scientists have studied the variety of nanoparticles that can easily penetrate these compounds, bind with them and help break them apart through chemical reactions that remove harmful toxic materials. Another specific application is the use of nanotechnology in cleaning up landfills where toxic waste may have been stored for a long time.
Nanotechnology can also be used to develop more environmentally friendly products that are safe for human consumption. For example, nanoparticles may be used to treat paper that is used in making paper bags to ensure that the food and other substances inside do not stick to them.
Paper pulp from the pulp and paper industry is now being treated with nanoparticles containing enzymes that break down any leftover material to ensure higher quality and safety for use in these bags. In another application, nanotechnology can be used to develop new foods and beverages to reduce their negative impacts on human health, animal health, or the environment.
Nano materials in food and beverages industry
In this context, nanomaterials are used to reduce the need for pesticides in the crop production process and thus reduce potential side effects on working animals and farm workers. For example, scientists have discovered that it is possible to use nanotechnology to develop foods containing bitter components, such as quinine, to treat malaria and other conditions.
Scientists are using this approach because bitter components may be toxic if consumed in large amounts without proper treatment. As a result, using nanomaterials can greatly simplify the processing and ensure that all toxic components are broken down while maintaining the functionality of these foods.
Nano technology and water purification
Thanks to nanotechnology, we now have new techniques that let us look at tiny amounts of water and dirt down to the level of individual atoms and molecules to study how they react when they come into contact with each other. We can use this information to understand what happens when these substances come together in the real world, in streams, rivers, and oceans. And we can then use this knowledge to develop smarter ways of cleaning up polluted water or soil. Let’s take a look at some examples:
Water filtration is a big challenge for developing countries where there is little money for advanced water treatment technology. But using nanotechnology, we can create affordable water filters that can remove particles from the water and let the clean water through.
Cleaning oil spills
In the cleanup of oil spills, advanced solvent-like chemicals are used to help break down a slick into tiny droplets that can then be absorbed by clay or sand. Nanomaterials can help create stronger solvents that absorb the oil more quickly and completely. Experts are already developing this technology at laboratories like Argonne National Laboratory in Illinois and Nanjing University in China.
Detecting virus and bacteria in water
Nanoparticles can also be used as powerful indicators for detecting pollutants such as bacteria and viruses in water samples. Scientists at the University of Michigan have used nanoparticles as markers to detect and track pathogenic microorganisms in contaminated water. Researchers are already using this technology at Oxford University in the UK and at Nanjing University.
Filtering heavy metals
Nanotechnology can also filter heavy metals like arsenic, lead, mercury, and cadmium from soil. The nanoparticle-based technology developed by researchers at Stanford University can separate soil into three different fractions that can be processed separately for recycling their resources. Although this is a very early stage of development, there is hope that this technology will help us clean up polluted soils in urban environments that are decades old.
