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Nomming on Nanotechnology: The Presence of Nanoparticles in Food and Food Packaging

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Nomming on Nanotechnology: The Presence of Nanoparticles in Food and Food Packaging

Nanotechnology is found in a variety of sectors—drug administration, water filtration, and solar technology, to name a few—but what you may not know is that nanotechnology could have been in your last meal.

Over the last ten years, the food industry has been utilizing nanotechnology in a multitude of ways.1 Nanoparticles can increase opaqueness of food coloring, make white foods appear whiter, and even prevent ingredients from clumping together.1 Packaging companies now utilize nano-sized clay pieces to make bottles that are less likely to break and better able to retain carbonation.2 Though nanotechnology has proven to be useful to the food industry, some items that contain nanoparticles have not undergone any safety testing or labeling. As more consumers learn about nanotechnology’s presence in food, many are asking whether it is safe.

Since the use of nanotechnology is still relatively new to the food industry, many countries are still developing regulations and testing requirements. The FDA, for example, currently requires food companies that utilize nanotechnology to provide proof that their products won’t harm consumers, but does not require specific tests proving that the actual nanotechnology used in the products is safe.2 This oversight is problematic because while previous studies have shown that direct contact with certain nanoparticles can be harmful for the lungs and brain, much is still unknown about the effects of most nanoparticles. Currently, it is also unclear if nanoparticles in packaging can be transferred to the food products themselves. With so many uncertainties, an activist group centered in Washington, D.C. called Friends of the Earth is advocating for a ban on all use of nanotechnology in the food industry.2

However, the situation may not require such drastic measures. The results of a study last year published in the Journal of Agricultural Economics show that the majority of consumers would not mind the presence of nanotechnology in food if it makes the food more nutritious or safe.3 For example, one of the applications of nanotechnology within the food sector focuses on nanosensors, which reveal the presence of trace contaminants or other unwanted microbes.5 Additionally, nanomaterials could be used to make more impermeable packaging that could protect food from UV radiation.5

Nanotechnology could also be applied to water purification, nutrient delivery, and fortification of vitamins and minerals.5 Water filters that utilize nanotechnology incorporate carbon nanotubes and alumina fibers into their structure, which allows microscopic pieces of sediment and contaminants to be removed from the water.6 Additionally, nanosensors made using titanium oxide nanowires, which can be functionalized to change color when they come into contact with certain contaminants, can help detect what kind of sediment is being removed.6 Encapsulating nutrients on the nanoscale-level, especially in lipid or polymer-based nanoparticles, increases their absorption and circulation within the body.7 Encapsulating vitamins and minerals within nanoparticles slows their release from food, causing absorption to occur at the most optimal part of digestion.4 Coatings containing nano-sized nutrients are also being applied to foods to increase their nutritional value.7 Therefore, there are many useful applications of nanoparticles that consumers have already shown to support.

While testing and research is an ongoing process, nanotechnology is already making food safer and healthier for consumers. The FDA is currently studying the efficacy of nanotechnology in food under the 2013 Nanotechnology Regulatory Science Research Plan. Though the study has not yet been completed, the FDA has stated that in the interim, it “supports innovation and the safe use of nanotechnology in FDA-regulated products under appropriate and balanced regulatory oversight.”8,9 As nanotechnology becomes commonplace, consumers can also expect to see an increase in the application of nanotechnology in food and food packaging in the near future.

References

  1. Ortiz, C. Wait, There's Nanotech in My Food? http://www.popularmechanics.com/science/health/a12790/wait-theres-nanotechnology-in-my-food-16510737/ (accessed November 9, 2015).
  2. Biello, D. Do Nanoparticles in Food Pose a Health Risk? http://www.scientificamerican.com/article/do-nanoparticles-in-food-pose-health-risk/ (accessed October 1, 2015).
  3. Yue, C., Zhao, S. and Kuzma, J. Journal of Agricultural Economics. 2014. 66: 308–328. doi: 10.1111/1477-9552.12090
  4. Sozer, N., & Kokini, J. Trend Biotechnol. 2009. 27(2), 82-89.
  5. Duncan, T. J. Colloid Interface Sci. 2011. 363(1), 1-24.
  6. Inderscience Publishers. (2010, July 28). Nanotechnology for water purification. ScienceDaily. (accessed March 3, 2016)
  7. Srinivas, P. R., Philbert, M., Vu, T. Q., Huang, Q., Kokini, J. L., Saos, E., … Ross, S. A. (2010). Nanotechnology Research: Applications in Nutritional Sciences. The Journal of Nutrition, 140(1), 119–124.
  8. U.S. Food and Drug Administration. http://www.fda.gov/ScienceResearch/SpecialTopics/Nanotechnology/ucm273325.htm (accessed November 9, 2015).
  9. U.S. Food and Drug Administration. (2015). http://www.fda.gov/ScienceResearch/SpecialTopics/Nanotechnology/ucm301114.htm (accessed November 9, 2015).

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Homo Naledi – A New Piece in the Evolutionary Puzzle

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Homo Naledi – A New Piece in the Evolutionary Puzzle

Human beings share 96% of their genome with chimpanzees,1 which is why modern science has accepted the concept that humans and apes share a recent common ancestor. However, our understanding of the transition from these ancient primates to the bipedal, tool-wielding species that conquered the globe is less clear than many realize. One crucial missing chapter in the evolutionary story is the origin of our very own genus, Homo. Scientists believe that somewhere between two and three million years ago, the hominid species Australopithecus afarensis evolved into the first recognizably human species, Homo erectus. However, the details of this genealogical shift have remained a mystery. In 2013, a discovery made in the Rising Star cave by two recreational cavers may have provided revolutionary insight into this intractable problem.

The Rising Star cave lies 30 miles outside the city of Johannesburg in northern South Africa. A popular destination for spelunkers for the past 50 years, this cave is well-known and has been extensively mapped.2 Two years ago, Steven Tucker and Rick Hunter dropped into the Rising Star cave in an effort to discover new extensions to the cave, with the hope of finding something more.2 They found a tight crevice that was previously unexplored, which led to a challenging forty-foot drop through a chute. At the bottom, Hunter and Tucker came across scattered bones and fossils in what would later be named the Dinaledi chamber.2 Hunter and Tucker consulted with Dr. Lee Berger, a paleoanthropologist at the University of Witwatersrand. It was clear to Dr. Berger that these fossils were not of modern humans -- an ancient hominid species had been discovered.2

Within weeks of this discovery, Dr. Berger assembled a qualified team and set up camp at the mouth of the Rising Star cave. In the largest hominid artifact discovery in Africa, over one thousand bones from multiple bodies were extracted and analyzed.2

As the fossils were being transferred out of the cave, paleoanthropologists at the surface worked to piece together a skeleton. Some aspects of this species’ bone structure were distinctly human, like the long thumbs, long legs, and arched feet.2 Other features, including curved fingers and a flared pelvis, were indicative of a more primitive animal.2 A large skull fragment from above the left eye of one of the skeletons allowed scientists to definitively determine this hominid’s genus.

The Australopithecus skull is characterized by a large orbital ridge above the eye, with a deep concavity behind it, leading to a flatter face with pronounced brows.3 The skull fragment collected by the team, however, had a shorter ridge and less of an indentation above the frontal lobe.3 This finding led the team to conclude that they had discovered a new member of the Homo genus, which Dr. Berger named Homo naledi. ‘Naledi’ in the Sotho language means ‘star,’ a reference to the vivid stalactites emanating from the ceiling of the Dinaledi chamber.3

Dr. Berger’s discovery in the Rising Star cave was an incredible breakthrough, but finding fossils is only half the battle. The next step is to find a place for this species in the million-year narrative of human evolution we have created.

In accomplishing this feat, a logical place to start is considering how the fossils of Homo naledi ended up in their final resting place. There were no signs of predation, as no other animal fossils were found at this location. In addition, these fossils accumulated gradually, meaning that the bodies did not all die from a single event. Dr. Berger postulated that these bodies were placed there with purpose, but intentional body disposal is an advanced social behavior which, up to this point, has only been exhibited by more evolved Homo species. The brain size of the discovered hominids is estimated to be between 450 and 550 cubic centimeters, about one third the size of Homo sapiens brain and only marginally larger than that of a chimpanzee.3 The possibility of such a small-brained animal engaging in intentional body disposal challenges ideas about the cognitive abilities necessary for such advanced social behavior. Dr. William Jungers, chair of anatomical sciences at Stony Brook University, argues that advanced social intelligence was not likely at play in this instance. He claims that “intentional corpse disposal is a nice sound bite, but more spin than substance […] dumping conspecifics down a hole may be better than letting them decay around you.”4

The idea of intentional body disposal is not the only one of Dr. Berger’s conclusions that has attracted criticism. Some in the scientific community argue that Homo naledi is a distant cousin, not a direct ancestor, of modern humans. Others, like UC Berkeley’s Dr. Tim White, argue that "new species should not be created willy-nilly,” and believe that these discoveries may just be fossils of Homo erectus.5 Biologist Dr. David Menton takes the small brain size of these hominids as well as well as their “sloped face” and “robust mandible” as indication that Homo naledi does not even belong in the Homo genus.6

It is clear that while the Homo naledi fossils are extremely significant in the scientific community, their placement within the story of human evolution is contentious. Our inability to definitively date the fossils makes the task even more challenging. However, Homo naledi’s unique mosaic of human and ape-like features provides support for a new model of human evolution that has recently gained traction in the scientific community. While scientists would prefer to draw a family tree of human ancestors with modern humans at the top, our evolution is not so simple. Dr. Berger likens the reality of evolution to a braided stream.2 Like a collection of tributaries all contributing to a river basin, humans may have been the product of a collection of human ancestors, each contributing to our existence differently. We may never fully understand where we came from, but discoveries like Homo naledi bring us a little bit closer to completing the evolutionary puzzle.

References

  1. Spencer, G. New Genome Comparison Finds Chimps, Humans Very Similar at the DNA Level. National Human Genome Research Institute [Online], August 31, 2005. https://www.genome.gov/15515096 (accessed March 1st, 2016)
  2. Shreeve, J. This Face Changes the Human Story. But How? National Geographic [Online], September 10, 2015. http://news.nationalgeographic.com/2015/09/150910-human-evolution-change/ (accessed January 17, 2016)
  3. Berger, L. R. et al. ELife [Online] 2015, 4. http://elifesciences.org/content/4/e09560 (accessed January 16, 2016)
  4. Bascomb, B. Archaeology's Disputed Genius. PBS NOVA NEXT [Online], September 10, 2015. http://www.pbs.org/wgbh/nova/next/evolution/lee-berger/ (accessed January 19, 2016)
  5. Stoddard, E. Critics question fossil find, but South Africa basks in scientific glory. UK Reuters [Online], September 16, 2015. http://uk.reuters.com/article/us-safrica-fossil-idUKKCN0RG0Z120150916 (accessed January 19, 2016)
  6. Dr. Mitchell, E. Is Homo naledi a New Species of Human Ancestor? Answers in Genesis [Online], September 12, 2015. https://answersingenesis.org/human-evolution/homo-naledi-new-species-human-ancestor/ (accessed January 17, 2016)

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