Glossary
This glossary has been produced to be of help to readers of this
particular text. It has been compiled with the aid of a number of glossaries and
dictionaries, and as such should not be considered to be an approved glossary of
WHO.
algal bloom: abnormally increased biomass of algae in a
lake, river or ocean.
aliphatic hydrocarbons: chemical compounds including carbon
and hydrogen with a straight structure.
aromatic hydrocarbons: chemical compounds including carbon
and hydrogen with a structure including at least one benzene ring.
ascariasis: disease caused by infection with Ascaris or
related ascarid nematodes.
ascites: accumulation of serous fluid in the abdominal
cavity.
atherosclerosis: a disease in which fat compounds build up
on the inside of arteries, potentially blocking blood flow.
atmosphere: gaseous envelope that surrounds Earth and which
is subdivided into the troposphere, stratosphere and mesosphere.
attenuated vaccine: vaccine based on live infectious
material that has been treated in such a way that it creates an antibody
response but does not cause the disease.
attributable risk: the proportion of a disease or other
outcome in exposed individuals that can be attributed to the exposure of
interest.
biofuel: renewable hydrocarbon fuel, usually alcohol, e.g.
methanol, ethanol, derived from corn (maize) and other grains.
"blackfoot disease": disease reported in China
of the peripheral blood vessels which is caused by arsenic exposure. The disease
constricts the arteries, the blood flow is diminished and the feet look black.
chlorofluorocarbons (CFCs): halocarbons that are major
greenhouse gases. CFCs are of human origin and have long atmospheric lifetimes
(more than 100 years). They are destroyed only by photolytic destruction in the
stratosphere where they cause ozone depletion.
coliform: general, ill-defined term used to denote
gram-negative, fermentative rods that inhabit the intestinal tract of man and
other animals.
copepod: any member of the subclass Copepoda. (Copepoda are
abundant, freeliving, freshwater and marine crustaceans of fundamental
importance to the aquatic food-chain in both marine and freshwater
environments.)
cor pulmonale: in chronic cases characterized by
hypertrophy of the right ventricle, resulting from disease of the lungs; in
acute cases, characterized by dilation and failure of the right side of the
heart due to pulmonary embolism.
Cryptosporidium: genus of coccidian sporozoans that are
important pathogens of calves and other domestic animals, and common
opportunistic parasites of humans that flourish under conditions of compromised
immune function.
cutaneous melanoma: type of skin cancer. A melanoma is a
malignant neoplasm, derived from cells that are capable of forming melanin.
cyanobacterial poisoning: reaction to the toxins produced
by cyanobacteria.
dengue fever: disease of tropical and sub-tropical regions,
caused by mosquitotransmitted dengue viruses.
dracunculiasis: also called guinea-worm disease, caused by
a parasite whose larvae can grow under the skin, reaching up to one metre in
length.
El Niño: name originally given by local inhabitants to a
weak warm ocean current flowing along the coast of Ecuador and Peru. El Niño
occurs irregularly, but approximately every four years on average.
endemic disease: the constant presence of a disease or
infectious agent within a given geographic area or population group; may also
refer to the usual prevalence of a given disease within such area or group.
epidemic: the occurrence in a community or region of cases
of an illness, specific health-related behaviour or other health-related events
clearly in excess of normal expectancy.
erethism: an abnormal state of excitement, irritation or
sensitivity to stimulation, either general or local.
eutrophication: the occurrence of high nutrient levels in
freshwater and marine ecosystems, usually resulting in excessive plant growth
and the death of animal and some plant life due to oxygen deprivation
filariasis: presence of filariae in the body, occurring in
tropical and subtropical regions.
fluorosis: condition caused by an excessive intake of
fluorides, characterized mainly by mottling, staining, or hypoplasia of the
enamel of the teeth.
food security: a situation in which all households have
both physical and economic access to adequate food for all members and where
households are not at risk of losing such access.
free radical: highly reactive chemical molecule that has at
least one unpaired electron.
greenhouse gas: gas that absorbs radiation emitted by
Earth's surface and clouds. The effect is a local trapping of part of the
absorbed energy and a tendency to warm Earth's surface. Water vapour,
carbon dioxide, nitrous oxide, methane, and ozone are the primary greenhouse
gases in Earth's atmosphere.
half-life: period during which the radioactivity of a
radioactive substance decreases to half of its original value; similarly applied
to the decrease in activity of any unstable active substance with time.
halocarbons: generic term to describe a group of human-made
chemicals that contains carbon and members of the halogen family. Halocarbons
include chlorofluorocarbons and haloes, substances that deplete stratospheric
ozone.
haloes: various gaseous compounds of carbon, bromine and
other halogens, usually bromoflouromethanes, used to extinguish fires, that
contribute to destruction of stratospheric ozone.
helminth: intestinal vermiform parasite; primarily
nematodes, cestodes, trematodes, and acanthocephalans.
hepatomegaly: enlargement of the liver.
incidence: the number of cases of illness commencing, or of
persons falling ill, during a given time period within a specified population.
Internet: global computer network providing access to and
dissemination of a vast amount of information.
ionizing radiation: electromagnetic or particle radiation
of a sufficient energy to cause ionization in biological cells.
isotope: one of two or more nuclides that are chemically
identical yet differ in mass number.
Japanese encephalitis: encephalitis (inflammation of the
brain) caused by a mosquito-transmitted Flavivirus, affecting large populations
in ricegrowing, suburban, and rural regions of South-East Asia.
keratosis: any lesion on the epidermis marked by the
presence of circumscribed overgrowths of the horny layer.
leishmaniasis: infection with a species of Leishmania;
transmission is by various sandfly species of the genus Phlebotomus or
Lutzomyia.
leptospirosis: illnesses caused by infection with
Leptospira; transmission is associated with contact with infected animals or
water contaminated with rat urine.
manufacturing value added: the difference between the value
of goods and the cost of materials or supplies that are used in producing them.
Value added is derived by subtracting the cost of raw materials, parts,
supplies, fuel, goods purchased for resale, electric energy, and contract work
from the value of shipments. It is the best money gauge of the relative economic
importance of a manufacturing industry because it measures that industry's
contribution to the economy rather than its gross sales.
mesothelioma: a cancer in the mesothelial tissues, usually
in the lining of the lung.
nuclide: particular (atomic) nuclear species with defined
atomic mass and number.
oblast: Russian word for "region".
odds ratio: epidemiological term used to express the
relative risk of disease when comparing groups. It is the ratio of the odds of
exposure among the cases of disease to the odds of exposure in the controls.
oedema: swelling caused by the accumulation of fluid in
body tissues.
onchocerciasis: tropical disease caused by a filarial
parasite transmitted by blackflies.
ozone: form of the element oxygen with three atoms instead
of the two that characterize normal oxygen molecules. Ozone (O3) is
an important greenhouse gas. The stratosphere contains 90% of all the
O3 present in the atmosphere that absorbs harmful ultraviolet
radiation.
pH: measure of the acidity or alkalinity of a solution,
ranging from 0 (acidic) to 7 (neutral) to 14 (alkaline).
parenchymal lung disease: disease of lung due to its
disfunction.
peripheral neuropathy: disease involving the peripheral
nerves.
peripheral vascular disease: disease of the peripheral
blood vessels
pertussis: commonly called whooping cough, caused by
Bordetella pertussis.
photovoltaic: term applied to devices that creates
electricity when exposed to light.
"polluter pays" principle: a system of charges
on the person or company that cause pollution.
primary health care: essential health care made accessible
at a cost the country and community can afford, with methods that are practical,
scientifically sound and socially acceptable.
prevalence: proportion of persons within a given population
who are currently affected by a particular disease or risk factor.
radiative forcing: a simple measure of the importance of a
potential climate change mechanism. The amount of perturbation of the energy
balance of the Earth-atmosphere system following, for example, a change in
carbon dioxide concentrations or a change in the output of the sun.
radionuclide: a nuclide of artificial or natural origin
that exhibits radioactivity.
radon: radioactive element, resulting from the breakdown of
radium.
relative risk: ratio of risk of occurrence of a disease in
one group as compared to the risk of occurrence in another group.
residual house-spraying: spraying of the internal walls of
houses with an insecticide in formulation and dose that ensures prolonged (i.e.
residual) action.
rotavirus: wheel-shaped virus that causes infantile acute
gastroenteritis and diarrhoea.
schistosomiasis: infection with species of Schistosoma.
Manifestations of this disease vary with the infecting species.
secondary (photochemical) pollutants: air pollutants
created by chemical reactions in the atmosphere from other pollutants that have
been emitted from motor vehicles or industry.
serotype: group or category of bacteria or other
microorganisms that have a certain set of antigens in common or against which
common antibodies are produced; the combination of antigens by which such a
group is categorized.
stomatitis: inflammation of the mucous membrane of the
mouth.
stratosphere: highly stratified and stable region of the
atmosphere above the troposphere extending from about 10 km to 50 km.
subclinical: without clinical manifestations; generally the
early stage of an infection or other disease before symptoms and signs become
clinically apparent.
trachoma: infectious inflammation of the eye, often
associated with lack of water for personal hygiene.
teratogenesis: a process that damages the growth of the
fetus in utero.
trematode: flat worm of the class Trematoda, including the
parasitic worms called "flukes". Trematodes that cause disease in
humans have intermediate stages in snails.
troposphere: lowest part of the atmosphere in which clouds
and weather phenomena occur. The troposphere is defined as the region in which
temperatures generally decrease with height.
trypanosomiasis: infection with protozoa, Trypanosoma
including American trypanosomiasis (Chagas disease) or African trypanosomiasis.
vibrio: type of actively mobile bacteria. The species
include the cholera vibrios, highly pathogenic for humans.
zoonosis: infectious disease of vertebrate animals, such as
rabies, that can be transmitted to
humans.
