cancer: Any of more than 100 different diseases, each characterized by the rapid, uncontrolled growth of abnormal cells. The development and growth of cancers, also known as malignancies, can lead to tumors, pain and death.
chemical: A substance formed from two or more atoms that unite (bond) in a fixed proportion and structure. For example, water is a chemical made when two hydrogen atoms bond to one oxygen atom. Its chemical formula is H2O. Chemical also can be an adjective to describe properties of materials that are the result of various reactions between different compounds.
cholesterol: A fatty material in animals that forms a part of cell walls. In vertebrate animals, it travels through the blood in little vessels known as lipoproteins. Excessive levels in the blood can signal risks to blood vessels and heart.
colleague: Someone who works with another; a co-worker or team member.
component: Something that is part of something else (such as pieces that go on an electronic circuit board or ingredients that go into a cookie recipe).
compound: (often used as a synonym for chemical) A compound is a substance formed when two or more chemical elements unite (bond) in fixed proportions. For example, water is a compound made of two hydrogen atoms bonded to one oxygen atom. Its chemical symbol is H2O.
concentration: (in chemistry) A measurement of how much of one substance has been dissolved into another.
environment: The sum of all of the things that exist around some organism or the process and the condition those things create. Environment may refer to the weather and ecosystem in which some animal lives, or, perhaps, the temperature and humidity (or even the placement of things in the vicinity of an item of interest).
environmental science: The study of ecosystems to help identify environmental problems and possible solutions. Environmental science can bring together many fields including physics, chemistry, biology and oceanography to understand how ecosystems function and how humans can coexist with them in harmony. People who work in this field are known as environmental scientists.
fluorine: An element first discovered in 1886 by Henri Moissan. It takes its name from the Latin word meaning “to flow.” Very reactive, chemically, this element had little commercial use until World War II, when it was used to help make a nuclear-reactor fuel. Later, it was used as ingredients (fluorocarbons) in refrigerants and aerosol propellants. Most recently, it has found widespread use to make nonstick coatings for frying pans, plumbers’ tape, and waterproof clothing.
landfill: A site where trash is dumped and then covered with dirt to reduce smells. If they are not lined with impermeable materials, rains washing through these waste sites can leach out toxic materials and carry them downstream or into groundwater. Because trash in these facilities is covered by dirt, the wastes do not get ready access to sunlight and microbes to aid in their breakdown. As a result, even newspaper sent to a landfill may resist breakdown for many decades.
perfluorooctanoic acid (PFOA): One of a host of synthetic, fluorine-rich molecules designed to keep water, oils and other materials from sticking to something. It is one of the most heavily studied members of a large family of very persistent, fluorine-rich compounds used as a nonstick coating and fabric treatment (to repel water and stains). Data in animals suggest that ingestion or inhalation of this compound could cause harm. Sometimes known as C8, this abbreviation denotes the number of carbon atoms making up the molecule’s backbone (and to which fluorine atoms are bound).
physicist: A scientist who studies the nature and properties of matter and energy.
polyfluoroalkyl substances (PFAS): Also known as perfluorocarbons and perfluorinated chemicals. These synthetic (human-made) chemicals contain a long chain of linked carbon atoms that act like a backbone from which fluorine atoms dangle (like little legs). They are long lived chemicals and have the ability to build up in organisms (including people). They have gained widespread industrial use for being stain- and water-repellent and having general non-stick properties. Among the best-known examples is Teflon.
risk: The chance or mathematical likelihood that some bad thing might happen. For instance, exposure to radiation poses a risk of cancer. Or the hazard — or peril — itself. (For instance: Among cancer risks that the people faced were radiation and drinking water tainted with arsenic.)
screening: A health test that is done early, before any symptoms are present. That can help find disease when it is easiest to treat. Screenings can include blood tests (such as for HIV, diabetes or high cholesterol), X-rays or scans (such as mammograms for breast cancer).
technology: The application of scientific knowledge for practical purposes, especially in industry — or the devices, processes and systems that result from those efforts.
thyroid: A gland in the neck that releases hormones, which play a pivotal role in directing development and metabolism (the use of food as fuel). The gland is relatively small, with two lobes separated by a bridge-like structure. Some therefore refer to its shape as resembling a butterfly.