acidic: An adjective for materials that contain acid. Acidic materials often are capable of dissolving away some minerals such as carbonate, or preventing their formation in the first place.
behavior: The way something, often a person or other organism, acts towards others, or conducts itself.
blood pressure: The force exerted against vessel walls by blood moving through the body. Usually this pressure refers to blood moving specifically through the body’s arteries. That pressure allows blood to circulate to our heads and keeps the fluid moving so that it can deliver oxygen to all tissues. Blood pressure can vary based on physical activity and the body’s position. High blood pressure can put someone at risk for heart attacks or stroke. Low blood pressure may leave people dizzy, or faint, as the pressure becomes too low to supply enough blood to the brain.
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.
chelate: (in public health) To administer a chelating agent, one that will bind with certain metals (often lead) to remove them from the body. This treatment is known as chelation therapy.
cognitive: A term that relates to mental activities, such as thinking, learning, remembering and solving puzzles.
corrode: (n. corrosion) A chemical process that weakens or destroys normally robust materials, such as metals or rock.
database: An organized collection of related data.
depression: (in medicine) A mental illness characterized by persistent sadness and apathy. Although these feelings can be triggered by events, such as the death of a loved one or the move to a new city, that isn’t typically considered an “illness” — unless the symptoms are prolonged and harm an individual’s ability to perform normal daily tasks (such as working, sleeping or interacting with others). People suffering from depression often feel they lack the energy needed to get anything done. They may have difficulty concentrating on things or showing an interest in normal events. Many times, these feelings seem to be triggered by nothing; they can appear out of nowhere.
develop: To emerge or to make come into being, either naturally or through human intervention, such as by manufacturing. (in biology) To grow as an organism from conception through adulthood, often undergoing changes in chemistry, size, mental maturity or sometimes even shape.
disorder: (in medicine) A condition where the body does not work appropriately, leading to what might be viewed as an illness. This term can sometimes be used interchangeably with disease.
economics: The social science that deals with the production, distribution and consumption of goods and services and with the theory and management of economies or economic systems. A person who studies economics is an economist.
element: (in chemistry) Each of more than one hundred substances for which the smallest unit of each is a single atom. Examples include hydrogen, oxygen, carbon, lithium and uranium.
Environmental Protection Agency: (or EPA) A national government agency charged with helping create a cleaner, safer and healthier environment in the United States. Created on Dec. 2, 1970, it reviews data on the possible toxicity of new chemicals (other than foods or drugs, which are regulated by other agencies) before they are approved for sale and use. Where such chemicals may be toxic, it sets limits or guidelines on how much of them may be released into (or allowed to build up in) the air, water or soil.
epidemiologist: Like health detectives, these researchers look to link a particular illness to what might have caused it and/or allowed it to spread.
filter: (n.) Something that allows some materials to pass through but not others, based on their size or some other feature. (v.) The process of screening some things out on the basis of traits such as size, density, electric charge. (in physics) A screen, plate or layer of a substance that absorbs light or other radiation or selectively prevents the transmission of some of its components.
friction: The resistance that one surface or object encounters when moving over or through another material (such as a fluid or a gas). Friction generally causes a heating, which can damage a surface of some material as it rubs against another.
high blood pressure: The common term for a medical condition known as hypertension. It puts a strain on blood vessels and the heart.
immune: (adj.) Having to do with immunity. (v.) Able to ward off a particular infection. Alternatively, this term can be used to mean an organism shows no impacts from exposure to a particular poison or process. More generally, the term may signal that something cannot be hurt by a particular drug, disease or chemical.
infrastructure: The underlying structure of a system. The term usually refers to the basic physical structures and facilities on which a society depends. These include roads, bridges, sewers, drinking water supplies, electrical power grids and phone systems.
IQ: Short for intelligence quotient. It’s a number representing a person’s reasoning ability. It’s determined by dividing a person’s score on a special test by his or her age, then multiplying by 100.
kidney: Each in a pair of organs in mammals that filters blood and produces urine.
leach: (in geology and chemistry) The process by which water (often in the form of rain) removes soluble minerals or other chemicals from a solid, such as rock, or from sand, soil, bones, trash or ash.
lead: A toxic heavy metal (abbreviated as Pb) that in the body moves to where calcium wants to go (such as bones and teeth). The metal is particularly toxic to the brain. In a child’s developing brain, it can permanently impair IQ, even at relatively low levels.
mental health: A term for someone’s emotional, psychological and social well-being. It refers to how people behave on their own and how they interact with others. It includes how people make choices, handle stress and manage fear or anxiety. Poor mental health can be triggered by disease or might reflect a short-term response to life’s challenges. It can occur in people of any age, from babies to the elderly.
metal: Something that conducts electricity well, tends to be shiny (reflective) and is malleable (meaning it can be reshaped with heat and not too much force or pressure).
nutrient: A vitamin, mineral, fat, carbohydrate or protein that a plant, animal or other organism requires as part of its food in order to survive.
octane booster: Octane refers to a class of colorless, flammable hydrocarbons that emerge during the refining of petroleum into gasoline and other fuels. When a fuel’s octane level isn’t high enough, some auto engines will develop a ping, knocking sound or begin to hesitate. To avoid this, engineers created liquid fuel additives known as octane boosters. One notorious and widely used type in the middle of the 20th century contained the toxic, heavy metal lead.
panic disorder: A type of anxiety disorder. Its victims frequently experience sudden attacks of overwhelming fear and panic. Panic attacks can happen without an obvious cause. They often include strong physical reactions. People having such an attack sometimes feel like they are losing control, can’t breathe or even are having a heart attack.
particle: A minute amount of something.
Proceedings of the National Academy of Sciences: A prestigious journal publishing original scientific research, begun in 1914. The journal’s content spans the biological, physical and social sciences. Each of the more than 3,000 papers it publishes each year, now, are not only peer reviewed but also approved by a member of the U.S. National Academy of Sciences.
psychologist: A scientist or mental-health professional who studies the mind, especially in relation to actions and behaviors. Some work with people. Others may conduct experiments with animals (usually rodents) to test how their minds respond to different stimuli and conditions.
puberty: A developmental period in humans and other primates when the body undergoes hormonal changes that will result in the maturation of reproductive organs.
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.)
social: (adj.) Relating to gatherings of people; a term for animals (or people) that prefer to exist in groups. (noun) A gathering of people, for instance those who belong to a club or other organization, for the purpose of enjoying each other’s company.
sociologist: A scientist who studies the behaviors of groups of people, how those behaviors developed, and the organizations that people create to support communities (societies) of people.
standardized test: A test that is administered and scored in the same way for all students and usually is given to large populations of students (not just to individual classes). Schools administer such tests in certain subjects regularly so that they can track how well their students are performing in those school subjects. The test may be given as a paper-and-pencil exam or on a computer.
stroke: (in biology and medicine) A condition where blood stops flowing to part of the brain or leaks in the brain.
survey: To view, examine, measure or evaluate something, often land or broad aspects of a landscape. (with people) To ask questions that glean data on the opinions, practices (such as dining or sleeping habits), knowledge or skills of a broad range of people. Researchers select the number and types of people questioned in hopes that the answers these individuals give will be representative of others who are their age, belong to the same ethnic group or live in the same region. (n.) The list of questions that will be offered to glean those data.
symptom: A physical or mental indicator generally regarded to be characteristic of a disease. Sometimes a single symptom — especially a general one, such as fever or pain — can be a sign of any of many different types of injury or disease.
system: A network of parts that together work to achieve some function. For instance, the blood, vessels and heart are primary components of the human body’s circulatory system. Similarly, trains, platforms, tracks, roadway signals and overpasses are among the potential components of a nation’s railway system. System can even be applied to the processes or ideas that are part of some method or ordered set of procedures for getting a task done.
toxic: Poisonous or able to harm or kill cells, tissues or whole organisms. The measure of risk posed by such a poison is its toxicity.
waste: Any materials that are left over from biological or other systems that have no value, so they can be disposed of as trash or recycled for some new use.
womb: Another name for the uterus, the organ in mammals in which a fetus grows and matures in preparation for birth.