Environmental Science Flashcards
Absorption (in biology)
penetration of a substance into an organism and its cells by various processes, some specialized, some involving expenditure of energy (active transport), some involving a carrier system, and other involving passive movement down an electrochemical gradient. In mammals absorption is usually through the respiratory tract, gastrointestinal tract, or skin into the circulatory system and from the circulation into organs, tissues, and cells
Acceptable risk
the risk that has minimal effects or for which benefits outweight the potential hazards. Calculated risk of an increase of one case in a million people per year for cancer is usually considered to be negligible
Acid deposition
acidification occurs after the release of nitrogen oxide and sulfur dioxide from point or nonpoint sources into the atmostphere. Chemical processes may transform these chemicals into sulfuric and nitric acids. These are returned to the earth in snowfallk rain, fog, and dust and may deposit at distances far from the original sources
acute exposure
a single exposure to a toxic substance which may result in sever biological harm or death. Acute exposures are usually characterized as lasting no longer than a day, as compared to longer, continuing exposure over a period of time
additive effect
a biologic response to exposure to multiple substances that equals the sum of responses of all the individual substances added togerh
adverse health effect
a change in body function or cell structure that might lead to disease or health problems.
aerobic
life or process that require, or are not destroyed by, the presence of oxygen
aerosol
mixture of small droplets of particles (solid, liquid, or mixed) and a carrier gas (usually air)
Agency for Toxic Substances and DIsease Registry
The agency for Toxi c Substances and Disease Registry, based in Atlanta, is a federal public health agency of the U.S. HHS. ATSDR serves the public by using the best science, taking responsive public health actions, and providing trusted ehatlh information to prevent harmful exposures and diseases related to toxic substances
air toxics
any air pollutant for which a national ambient air quality standard (NAAQS) does not exist (i.e. excluding ozone, carbon monoxide, PM-10, sulfur dioxide, nitrogen oxide) that may reasonably be anticipated to cause cancer; respiratory, cardiovascular, or developmental effects; reproductive dysfunctions, neurological disorders, heritable gene mutations, or other serious or irreversible chronic or acute health effects in humans.
Alpha particl
a positively charged particle ejected spontaneously from the nuclei of some radioactive elements. It is identical to a helium nucleus that has a mass number of 4 and an electro static charge of +2. It has low penetrating power and a short range ( a few centimenters in air). THe most energetic alpha particle will generally fail to penetrate the dead layers of cells covering the skin and can be easily stopped by a sheet of paper. ALpha particles are hazardous when an alpha-emitting isotope is inside the body
ambient air
any unconfined portion of the atmosphere; open air, surrounding air
American Conference of Governmental Industrial Hygienists (ACGIH)
ACGIH is a member-based organization that advances occupational and environmental health. TLVs and BEIs
ANaerobic
a life or process that occurs in, or is not destroyed by, the absence of oxygen
analyte
a substance that is undergoing analysis or is being measured. For example, if the analyte is mercury, the lab test will determine the amount of mercury in the sample
antagonism (in toxicology)
combined effect of two or more factors that is smaller than the solitary effect of any one of those factors
anthropogenic
caused by or influenced by human activites
apoptosis
programmed cell death, the body’s normal method of disposing of damaged, unwanted, or unneeded cells
aqueous
of, relating to, or resembling water, made from, with, or by water
Aqueous solubility
the max concentration of a chemical that iwll dissolve in pure water at a referenc temperature
aquifer
underground geological formation, or group of formations, containing water. Are sources of groundwater for wells and spings
ALARA
As low as is reasonably achievable. Means making every reasonable
Assessment endpoint
an explicit expression of the environmental value that is to be protected, operationally defined by an ecological entity and its attributes. For example, salmon are valued ecological entities; reproduction and age class structure are some other important attributes.
asthma
chronic respiratory disease characterized by bronchoconstriction, excessive mucus secretion and edema of the pulmonary alveoli, resulting in difficulty in breathg out, wheezing, and cough.
B lymphocyte
a type of lymphocyte (white blood cells), produced in the bone marrow, which synthesizes and secretes antibodies in response to the presence of a foreign substance or one identified by it as being foreign
background level
the concentration of a substance in an environmental media (air, water, or soil) that occurs naturally or is not the result of human activities; 2. IN exposure assessment the concentration of a substance in a defined control area, during a fixed period of time before, during, or after a data-gathering operation
bacteria
microscopic living organisms. Bacteria in soil, water, or air may be pathogenic and cause illnesses in humans, animals, and plants. They can also be non-pathogenic and be beneficial in pollution control by metabolizing organic matter in sewage, oil spills, or other pollutants
basal metabolic rate
the rate at which heat is given off by an organism at complete rest
bedrock
the solid rock underneath surface soils
Bench-scale tests
laboratory testing of potential cleanup technologies
Beta particle
a charged particle emitted from a nucleus during radioactive decay, with a mass equal to 1/1837 that of a proton. A negatively charged beta particle is identical to an electron. A positively charged beta particle is called a positron. Large amounts of beta radiation may cause skin burns, and beta emitters are harmful if they enter the body. May be stopped by thin sheets of metal or plastic.
bioaccumulants
substances that increase in concentration in various tissues of living organisms as they take in contaminated air, water, or food because the substances are very slowly metabolized or excreted
biochemical oxygen demand (BOD)
a measure of the amount of oxygen consumed in the biological processes that break down organic matter in water. The greater the BOD< the greater the degree of pollution
biocide
substance intended to kill living organisms
biodegradable
capable of decomposing under natural conditions
biohazard
an agent of biological origin that has the capacity to produce deleterious effects on humans, e.e. microorganisms, toxins, and allergens derived from those organisms; and allergens and toxins derived from higher plants and animals
Biological Exposure Indices (BEI)
A guidance value recommended by ACGIH for assessing biological monitoring results
biologic monitoring
the measuring of hazardous substances in biologic materials (blood, hair, urine, breath) to determine whether exposure has occurred. e.g. blood test for lead
biologic uptake
the transfer of substances from the environment to plants, animals, and humans.
biomarker
a cellular or molecular indicator of exposure, health effects, or suceptibility. Can be used to measure internal dose, biologically effective dose, early biological response, altered structure or fuction, susceptability.
biomedical testing
testing of persons to find out whether a change in a body function might have occurred because of exposure to a hazardous substance
bioremediation
use of living organisms to clean up oil spills or remove other pollutants from soil, water, or wastewater; use of organisms such as non-harmful insects to remove agricultural pests or counteract diseases of trees, plants, and garden soil
biota
the animal and plant life of a given region
biotechnology
the indistrial use of living organisms (or parts of living organisms) to produce foods, drugs, or other products
bioterrorism
terrorism by intentional release or dissemination of biological agents (bacteria, viruses, or toxins) these may be in a naturally-occurring or in a human-modified form.
BOD5
the amount of dissolved oxygen consumed in five days by biological processes breaking down organic matter
body burden
total amount of a substance, organism, or noxious agent present in an organism at a given time
built environment
encompasses all buildings, spaces, and products that are created, or modified, by people. Includes homes, schools, workplaces, parks/recreation areas, greenways, business areas and transportation systems. It extends overhead in the form of electric transmission lines, underground in the form of waste disposal sites and subway trains, and across the country in the form of highways. Includes land-use planning and policies that impact our communities in urban, rural, and suburban areas.
cancer
any one of a group of diseases that occur when cells in the body become abnormal and grow or multiply out of control
