Organic Biochemistry

Nitrogen from Fertilizers: Too Much of a Good Thing

April 2010 (pp 5–7)

Author: Beth Nolte

Chemistry Connections: Equilibrium, Organic/Biochemistry, Reactions, Solids/Liquids/Gases

Description: Describes the nitrogen cycle and the role of excessive use of nitrogen fertilizers in polluting the environment. The chemistry of nitrogen, ammonia, oxides of nitrogen and nitrates are emphasized. Suggests that changes in farming methods can ameliorate the environmental effects. Includes sidebars on organic farming and the Haber-Bosch method of producing ammonia.

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Plastics Go Green

April 2010 (pp 10–12)

Author: Cynthia Washam

Chemistry Connections: Organic/Biochemistry, Sustainability

Description: Discusses the recent trend toward producing plant-based plastics—called bioplastics—from plants like sugar cane, potatoes and wheat as an alternative to using petroleum. Explains two types of bioplastics, polylactide acid and polyhydroxyalkanoate—polymers made from simple sugar molecules—and includes structural formulas for these. Gives background on plastics as polymers. Discusses pros and cons of bioplastics—for consumers and for the environment. Includes activity for students to make a compostable bioplastic.

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Green Gasoline: Fuel from Plants
February 2010 (pp 13–15)

Author: Michael Schirber

Chemistry Connections: Bonding, Organic/Biochemistry, Reactions, Thermochemistry

Description: Describes how molecules, like cellulose, found in plants like switchgrass and plant “leftovers” like corn stalks, can be made into gasoline. Uses lots of graphics to explain the use of zeolite catalysts in the process of stripping oxygen atoms from carbohydrate molecules to make hydrocarbon molecules that, in turn, make gasoline. Distinguishes green gasoline from biofuels like ethanol. Describes benefits of green gasoline.

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Anesthesia: Chemistry in the Operating Room
February 2010 (pp 8–9)

Author: Claudia M. Caruana

Chemistry Connections: History/Biography, Organic/Biochemistry, Solids/Liquids/Gases

Description: Describes and explains the way in which general and local inhaled anesthetics work in the human body. Provides the reader with some history of anesthesia—from 4200 BC to the present day—including nitrous oxide, ether and modern inhalation anesthetics, halogenated ethers. Discusses some biochemical mechanisms suggested to explain the effect of an anesthetic on the nervous system, although it also states the lack of a precise medical/scientific understanding of how anesthetics work.

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Hollywood's Special Effects - How Did They Do That?
December 2009 (pp 5–8)

Author: Diana Lutz

Chemistry Connections: Bonding, Organic/Biochemistry, Reactions, Solids/Liquids/Gases, Thermochemistry

Description: Describes how various special effects are created for movies, including fake snow, fake skin, fire and explosions. Some chemistry is detailed to explain how the materials are produced.

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Nanotechnology's Big Impact
October 2009 (pp 15–17)

Author: Nadia Halim

Chemistry Connections: Bonding, Organic/Biochemistry

Description: Nanotechnology utilizing the elements carbon and silicon create nanostructures (1-100 nanos large) for use in electronics, medicine (drug delivery systems), clean energy production (solar cells). Three basic structures are nanotubes, nanowires, and fullerenes (“Bucky balls”). Construction of a nanostructure by electron beam lithography and photolithography is illustrated.

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Chocolate, the New Health Food - Or Is It?
April 2009 (pp 13–15)

Author: Gail Kay Haines

Chemistry Connections: Organic/Biochemistry

Description: Details the various important chemical components and the purported health effects of pure, processed chocolate with structural formulas of caffeine, theobromine, anandamide, phenylethylamine, various polyphenols (antioxidants) and flavanols. Side bar shows production of chocolate extract from

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Bringing Chemistry to the Kitchen
February 2009 (pp 10–12)

Author: Patrice Pages

Chemistry Connections: Organic/Biochemistry, Reactions, Solids/Liquids/Gases, Solutions

Description: Experimental cooking based on some understanding of chemistry and physics but primarily experimental using new physical forms of ingredients in the mix. Influence of color on taste perception studied; good taste influences amount eaten (savoring means less eaten)

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Coffee: Brain Booster to Go?
December 2008 (pp 7–9)

Author: Gail Kay Hines

Chemistry Connections: Organic/Biochemistry

Description: Discusses chemicals contained in coffee, including caffeine (of course) and chlorogenic acids. Describes caffeine’s effects on the brain and the role of chlorogenic acids as major antioxidants in the body, as well as other positive health effects of drinking coffee, such as preventing tooth decay and intestinal infections by killing bacteria and relieving stress and reducing alcohol cravings. The article shows structural formulas for caffeine and a chlorogenic acid.

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Glowing Proteins with Promising Biological and Medical Applications
December 2008 (pp 12–14)

Author: Linda Zajac

Chemistry Connections: History/Biography, Organic/Biochemistry, Reactions

Description: Discusses research done to discover why crystal jellyfish glow in the dark, which led to discovery of green fluorescent protein (GFP, for short). Describes how GFP genes can be inserted into DNA of other cells that can then act as tracers as they travel throughout the body. Describes the uses of other colors of fluorescent proteins that have been discovered, including: tracking viruses in plant diseases, helping to cure brain diseases, and cancer therapy studies. Might be used in class in discussion of light emission and absorption and energy and wavelength of light.

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The Olympic Flame: Chemistry Held High
October 2008 (pp 4–5)

Author: Brian Rohrig

Chemistry Connections: Organic/Biochemistry, Reactions, Thermochemistry

Description: Describes the history of the Olympic torch, and its 135-day relay trip to Beijing for the 2008 Olympics, which included an underwater portion and a trip up Mt. Everest. Then discusses the chemistry of the torch itself, including its composition and the many different fuels used in the torch over the years. Chemistry includes equations for combustion of propane and ammonium perchlorate (for the underwater part of the trip).

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The Chemistry of Marathon Running
October 2008 (pp 6–8)

Author: Brian Rohrig

Chemistry Connections: Organic/Biochemistry, Thermochemistry

Description: Describes the author’s trials and tribulations running a marathon. Discusses aerobic and anaerobic respiration, the different fuels the body uses – carbohydrates (glucose, primarily glycogen), fats and protein – to fuel its muscles, and how the fuel changes with varying degrees of exercise. Article shows structural formulas of glucose and glycogen.

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Natural, Braided, Bleached, Colored, Straight, and Curly Hair: Thanks to Chemistry
October 2008 (pp 15–17)

Author: Lois Fruen

Chemistry Connections: Bonding, Organic/Biochemistry

Description: Talks about various chemicals and the roles they play in hair styling. Hair conditioners, antihumectants, styling products, hair dyes and hair straighteners are all described. Chemical structures are shown for many of the products. Bond types involved in hair are described.

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Sniffing Landmines
April 2008 (pp 7–9)

Author: Sarah Vos

Chemistry Connections: Organic/Biochemistry, Reactions, Thermochemistry

Description: Discusses the use of trained dogs to sniff out landmines, and the need for both the dogs and handlers to be well trained. Says TNT (trinitrotoluene), the explosive of choice for landmines, can release DNT (dinitrotoluene) vapors, which dogs smell. Compares efficacy of sniffing dogs to metal detectors. Also covers research being done by military and academic groups to produce detectors that work the same way dogs’ noses do. Formulas for TNT and DNT, and equation for detonation of TNT are given.

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The Forensics of Blood
February 2008 (pp 4–7)

Author: Brian Rohrig

Chemistry Connections: Organic/Biochemistry, Solutions

Description: Describes how chemists determine if a substance at a crime scene is blood (luminol and hydrogen peroxide or phenolphthalein and hydrogen peroxide), and if so, if it is human blood (rabbit antibody clotting test). Discusses blood as a colloid. Also tells how criminal investigators can determine blood type. Discusses useful information about blood stains – shape of blood droplets, transfer stains, projected stains. Two sidebars discuss the composition of blood, and the role of antibodies and antigens in determining blood type. The equation describing the reaction of luminal with hemoglobin is shown.

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"Follow the Carbon.” Follow the What?
February 2008 (pp 16–19)

Author: Lora Bleacher

Chemistry Connections: Atomic Theory, Nuclear, Organic/Biochemistry

Description: Describes the Sample Analysis at Mars (SAM) suite of instruments on board the Mars Science Laboratory (MSL), to land on Mars in late 2009 and stay there roving the surface collecting data. Instruments include laser spectrometer, gas chromatograph, and quadrupole mass spectrometer. Discussion of the value of studying carbon as an essential ingredient of life and its role in organic compounds ensues. Talks about isotopes of carbon providing information about the origin of the organic materials the SAM might detect.

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Percy Julian: Rising Above Racism
October 2007 (pp 13–15)

Author: Christen Brownlee

Chemistry Connections: History/Biography, Organic/Biochemistry

Description: Chronicles Julian’s early life as the grandson of slaves, his education at DePauw University, Harvard and the University of Vienna and his teaching career at DePauw, Fisk and Howard Universities. Describes his groundbreaking synthesis of alkaloids—physostigmine to treat glaucoma, derivatives of soybeans for a variety of applications and steroids like progesterone and cortisol. Also recounts Julian’s struggles to overcome the racism of the time.

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Retiring Old Tires
April 2007 (pp 11–13)

Author: Donald Jones and Helen Herlocker

Chemistry Connections: Bonding, Organic/Biochemistry, Sustainability

Description: Establishes tire fires as a serious environmental hazard. Describes the polymer chemistry used in manufacturing rubber. Makes the case for re-using old tires in three ways: burning them as a fuel (tire-derived fuel or TDF), shredding them and using them to help civil engineers in highways projects for drainage and landfills and grinding them into “crumb” size for use in making asphalt, playground surfaces and even for making new tires.

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Alice Ball: A Young Chemist Gave Hope to Millions
February 2007 (pp 16–19)

Author: Paul Wermager and Carl Heltzel

Chemistry Connections: History/Biography, Organic/Biochemistry

Description: Chronicles the history of the leper colony at Kalaupapa settlement on the Hawaiian island of Molokai and early attempts to treat leprosy (Hansen’s Disease). Traces the introduction of a modern treatment, chaulmoogra oil, the active ingredients of which are chaulmoogric acid and hydnocarpic acid. Both chemicals are insoluble in water, making them difficult to use in humans. Features biographical information on Alice Ball, a young African-American chemistry instructor at the University of Hawaii. Ball solved the insolubility of chaulmoogra oil in 1915, by preparing the ethyl esters of the fatty acids present in the oil, thus making the treatment available by injection. This method of treating Hansen’s Disease was the standard of care until sulfa drugs were introduced in the 1940’s.

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Corn—The A”maiz”ing Grain
December 2006 (pp 4–7)

Author: Gail Haines

Chemistry Connections: Organic/Biochemistry

Description: Describes the evolution of corn (grass derivative) over 8000 years with genetic changes through natural selection and deliberate genetic modification (inserting genes). Corn’s multiple uses—animal feed, alcohol fuel, food additive as corn syrup (modified for sweetness)—are highlighted. Unresolved controversy over the role of corn syrup in “causing” obesity.

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ChemSumer: Sticky Situation: The Wonders of Glue
December 2006 (pp 8–10)

Author: Linda Shiber

Chemistry Connections: Bonding, Organic/Biochemistry, Reactions, Solids/Liquids/Gases

Description: Glues produced “biologically” by animals as well as chemical mixes from human experimentation are explained in chemical terms. Even cilia of geckos utilize induced dipoles (London dispersion) between cilia and surfaces for attachment.

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Unusual Sunken Treasure
December 2006 (pp 11–13)

Author: Tim Graham

Chemistry Connections: Equilibrium, Organic/Biochemistry, Solids/Liquids/Gases, Solutions

Description: Raising a Norwegian sunken ship (torpedo, 1916) full of champagne requires understanding of the gas laws—effect of temperature, pressure on dissolved carbon dioxide in champagne. Asides on fermentation, processing champagne, what produces the fine bubbles.

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Sick Buildings—Air Pollution Comes Home
October 2006 (pp 12–14)

Author: Michelle Laliberte

Chemistry Connections: Nuclear, Bonding, Organic/Biochemistry, Reactions, Sustainability

Description: Homes can have multiple sources of pollution: biological (mold, dust mites), chemical (formaldehyde, radon, carbon monoxide). Chemistry of CO poisoning and formaldehyde resin formation shown.

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ChemSumer: The Dog Ate My Homework and Other Gut-Wrenching Tales

Author: Michael Tinnesand

Chemistry Connections: Bonding, Organic/Biochemistry

Description: Describes the digestive processes in animals, specifically a dog in this article, with emphasis on the breaking and reforming of chemical bonds in biomolecules. The role of enzymes is used to explain why cellulose, which is made up of glucose units, cannot be digested but starch, also made up of glucose, cannot. Article notes that most animals that feed on a cellulose-rich diet cannot digest cellulose and, therefore, have a symbiotic relationship with micro-organisms that break down the cellulose.

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Sneeze and Wheeze

April 2006 (pp 7–10)

Author: Roberta Baxter

Chemistry Connections: Organic/Biochemistry

Description: Five major topics covered here—the human respiratory system, allergies, allergy treatment, asthma, asthma treatment and the role of inflammation in allergies and asthma. Discusses the chemicals involved in allergies and asthma and their treatment.

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GreenChem: Biomimicry—Where Chemistry Lessons Come Naturally

April 2006 (pp 15–17)

Author: Kathryn Parent and Jennifer Young

Chemistry Connections: Organic/Biochemistry, Reactions

Description: This green chemistry article explains biomimicry—studying natural chemical processes and trying to duplicate them for technological purposes. Cites and explains examples—super-strong silk produced from amino acids by the golden orb weaver spider, the irritant made from hydroquinone and hydrogen peroxide and emitted by the bombardier beetle and the strong water-resistant glue produced by mussels.

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Nanomotors

April 2006 (pp 18–19)

Author: Anne Rosenthal

Chemistry Connections: Organic/Biochemistry, Reactions

Description: Describes and explains the structure and mechanism of the biological nanomotors that propel bacterial flagella. Compares electrical and biological motors. Emphasizes the role of proton diffusion in the cell as the driving force for the bio-motors. Gives examples of synthetic nanomotors made from carbon nanotubes, and catalytic nanomotors made of platinum and gold and propelled by the decomposition of hydrogen peroxide.

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ChemMystery: Real or Fake? The James Ossuary Case
February 2006 (pp 8–10)

Author: Lois Fruen

Chemistry Connections: Atomic Theory, Equilibrium, History/Biography, Nuclear, Organic/Biochemistry

Description: Discusses methods used to authenticate antiquities, focusing on radiocarbon dating. The process and the background science are described. Other methods described: hardness and density testing, microscopic analysis of mineral composition, mass spectrometry to measure O-18 to O-16 isotope ratios. Scientists reported the artifacts were fake, but then further research by other scientists refuted the fakery claims. The question remains unanswered. Chemistry centers on isotopic composition and presence of carbon dioxide in groundwater dissolving calcite (equilibrium equations provided).

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ChemSumer: Liquid Crystal Displays
October 2005 (pp 6–9)

Author: Lois Fruen

Chemistry Connections: Bonding, Organic/Biochemistry, Solids/Liquids/Gases

Description: Talks about electronic games and other electronic devices that use liquid crystal displays (LCDs). Describes what liquid crystals are—long polar organic molecules, how they work—they align themselves in an electric field, but not too tightly, and polarizing films and polarized light—the process by which liquid crystals are able to transmit (or not) light. Discusses twisted nematic liquid crystals and color display screens, as well as the future of LCDs. Also includes a sidebar on plasma display screens, which use phosphorescent cells containing noble gases that emit ultraviolet light when excited by electricity, subsequently exciting the electrons in the phosphors to emit visible light.

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ChemHistory: There’s Chemistry in Golf Balls!
October 2005 (pp 15–17)

Author: Brian Rohrig

Chemistry Connections: Bonding, History/Biography, Organic/Biochemistry

Description: Traces the history of the golf ball, from wood to featherie to guttie to mass-produced solid-rubber-core-with-rubber-thread-wrap to the pneumatic core to the myriad compositions of today’s golf balls. The invention of the superball is credited with major advances in golf ball technology. Describes the need for an inner core that is elastic and bounces back quickly after it is hit, and an outer layer that can deform, absorbing more of the energy of the swing. Discusses vulcanization of rubber polymer to improve coefficient of restitution (bounce).

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The Great Hartford Circus Fire

February 2005 (pp 4–7)

Author: Brendan Rimetz

Chemistry Connections: Bonding, History/Biography, Organic/Biochemistry, Reactions, Solutions

Description: Tells the history of a fire that destroyed the Ringling Brothers and Barnum & Bailey Circus “big top” tent in July, 1944 and killed or injured almost 900 people. Focuses on waterproofing agent, composed of paraffin wax and gasoline. Discusses polarity of water, and non-polarity of gasoline and paraffin, and why the latter two chemicals were used to waterproof the tent canvas, and describes the synergistic (in this case, synergistically BAD) effects of using the two organic substances together, and why firefighters using water to put out the fire were unsuccessful. Discusses second waterproofing substance, with little known about its composition. Sidebar tells a survivor’s story. Second sidebar discusses colloidal dispersions to dissolve polar and non-polar substances together.

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Carb Crazy
October 2004 (pp 6–8)

Author: Brain Rohrig

Chemistry Connections: Organic/Biochemistry, Thermochemistry

Description: Explains the chemical structure of different types of carbohydrates and their role in cellular respiration. Also explains the relationship of carbohydrates and blood sugar. Examines low-carb diets and how they work and how low-carb diets lead to ketosis, the conversion of fat to ketones. Offers pro and con research on the value of low-carb diets for teenagers.

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Lab on a Stick
October 2004 (pp 9–12)

Author: Christen Brownlee

Chemistry Connections: Acids/Bases, History/Biography, Organic/Biochemistry, Reactions, Solutions

Description: Recounts attempts to find an easy-to-use colorimetric urine test for diabetes. Includes early chemical testing, from the use of copper (II) sulfate-sodium hydroxide-ammonia reagent, to the advance made by Walter Compton who combined the reagents into tablet form (called Clinitest), to the modification made by Helen and Al Free which was a tablet that tested urine for ketone bodies. Describes the paper strip test, also developed by the Frees, which uses glucose enzymes to test for sugar in urine. Eventually the paper strip developed by the Frees contained ten tests in a single strip. The test strips are called Multistix-10SG. Article includes photos of the test strips. An interview with Helen Free follows the article.

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MysteryMatters: When Good Science Goes Bad!
October 2004 (pp 16–18)

Author: Tim Graham

Chemistry Connections: Organic/Biochemistry, Reactions

Description: Reviews the evidence used to convict a mother of poisoning her son with ethylene glycol and points out how analytical testing can yield inaccurate results. Also focuses on chemical reactions in the human body that can be used to identify chemicals present in the body. Explains the working of the gas chromatograph-mass spectrometer. A good forensic chemistry article.

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Chemsumer: Can Chemistry Stop What's Bugging You?
April 2004 (pp 8–10)

Author: Doris Kimbrough

Chemistry Connections: Organic/Biochemistry

Description: Examines major classes of insecticides—organochlorines (banned in the U.S.), carbamates, pyrethoids, and organophosphates—their chemical structure and their effect on humans. Describes the importance of acetylcholine in the nervous system of humans and the fact that some pesticides, like carbamates, compete with acetylcholine for the enzyme called acetylcholinesterase that controls the amount of acetylcholine in the nervous system. Explains that carbamates react with acetylcholinesterase and prevent it from controlling acetylcholine and that acetylcholine buildup in the nervous system can cause harmful physiological reactions. Describes this mechanism as the means by which insects are killed, but that it can be temporarily dangerous to humans as well. Notes that organophosphates can cause permanent damage in humans.

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Chemsumer: The Aspirin Effect: Pain Relief and More

February 2004 (pp 7–9)

Author: Doris Kimbrough

Chemistry Connections: History/Biography, Organic/Biochemistry, Reactions

Description: Relates the chemistry of non-steroidal anti-inflammatory drugs (NSAIDS) to the chemistry of prostaglandins and their role in the body’s pain producers. Explains that prostaglandins are lipids with a five-carbon ring as part of their structure. Also explains that prostaglandins are derived from arachidonic acid in a series of chemical reactions the article calls the arachidonic acid pathway. Recounts the history of aspirin and other NSAIDS like ibuprofen, acetaminophen and naproxen and explains that these compounds relieve pain in the body by inhibiting the production of prostaglandins.

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Vanilla! It’s Everywhere!
December 2003 (pp 4–6)

Author: Gail Haines

Chemistry Connections: Organic/Biochemistry, Nuclear, Reactions

Description: Describes historical origins of the most widely used flavoring, vanilla, sources of natural and methods to synthesize vanillin, chemical methods of analysis (authenticate natural vs. synthetic). Side bar describes most sensitive test using isotopic ratios of carbon to detect substitution of synthetic vanillin for natural.

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Chemistry in the Sunlight
October 2003 (pp 22–24)

Author: Jeannie Allen

Chemistry Connections: Organic/Biochemistry, Reactions, Solids/Liquids/Gases, Thermochemistry

Description: Positive and negative effects of ozone in our atmosphere—blocking UV radiation, negatively affecting biological tissue. Sources of ozone—volcanoes, burning fossil fuels. Additional “pollutants” (volatile organic compounds, VOC, and nitrogen oxides, NOx) and their effects are described.

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Asthma—Attack From the Air
September 2001 (pp 12–13)

Author: Helen Herlocker

Chemistry Connections: Organic/Biochemistry, Solids/Liquids/Gases

Description: Provides a look at the causes, mechanism and effects of asthma with an emphasis on its effect on teenagers. Points to various allergens like pollen, pollution, dust, molds and second-hand cigarette smoke as the basic causes. Colds, flu and other infections may also be causes. Emphasizes the strong link between air pollution and asthma. Lists some of the atmospheric chemicals that can act as asthma-causing triggers—sulfur dioxide (SO2), nitrogen oxides (NOx), carbon monoxide (CO), ground-level ozone (O3) and particulates

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