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Water: Microbial

Thesaurus of Terms Used in Microbial Risk Assessment:

5.6   Host Characterization and Health Effect Terms

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acquired immunity

A form of cellular defense which identifies certain foreign substances (antigens) as harmful to the body.  For this reason, the body can acquire resistance to a particular foreign agent.  (CancerWEB 2005)
RELATED TERMS: immunity

active immunity

An organisms resistance to disease or infection, developed because the organisms immune system has produced antibodies after an infection or inoculation.  (CancerWEB 2005)
Resistance developed in response to stimulus by an antigen (infecting agent or vaccine) and usually characterized by the presence of antibody produced by the host.  (MERREA 2005)
RELATED TERMS: immunity

acute

Occurring over a short time (compare with chronic).  (ATSDR 2004)
Referring to a health effect, sudden onset, often brief; sometimes loosely used to mean severe; referring to exposure, brief, intense, or short-term; sometimes specifically referring to a brief exposure of high intensity.  (MERREA 2005)
RELATED TERMS: contrast with chronic

acute effect

  1. Any toxic effect produced with a short period of time following an exposure, for example, minutes to a few days (EPA 2004)
  2. An adverse effect on any living organism in which severe symptoms develop rapidly and often subside after the exposure stops.  (EPA 2005e)
  3. Occurring over a short time.  (ATSDR 2004)
  4. Diseases or responses with short and generally severe course (often due to high pollutant concentrations).  (RAIS 2004, SRA 2004)

adverse effect

  1. A biochemical change, functional impairment, or pathologic lesion that affects the performance of the whole organism, or reduces an organism’s ability to respond to an additional environmental challenge.  (EPA 2003)
    (Adverse ecological effects) Changes considered undesirable because they alter valued structural or functional characteristics of ecosystems or their components.  (EPA 1998a)
  2. Change in morphology, physiology, growth, development, or life span of an organism that results in impairment of functional capacity or impairment of capacity to compensate for additional stress or increase in susceptibility to the harmful effects of other environmental influences.  Decisions on whether or not any effect is adverse require expert judgment.  (WHO 1994)
  3. Change in morphology, physiology, growth, development or lifespan of an organism that results in impairment of functional capacity or impairment of capacity to compensate for additional stress or increase in susceptibility to the harmful effects of other environmental influences.  (ILSI 2001)
  4. Change in the morphology, physiology, growth, development, reproduction or life span of an organism, system, or (sub) population that results in an impairment of functional capacity, an impairment of the capacity to compensate for additional stress, or an increase in susceptibility to other influences.  (IPCS/OECD 2004)
    RELATED TERMS: adverse health effect

Adverse effect is a general term that can be applied more broadly than the effects explicitly stated above.  All adverse health effects can be considered adverse effects, however not all adverse effects are adverse health effects.  Based on the definitions for the two terms, the distinction is whether health related symptoms are experienced.  For example, biochemical changes, pathological lesions, and changes in morphology may be classified as adverse effects even when they are only precursors to an adverse health effect.  Even though the two terms are not identical in meaning it is not unreasonable to classify disease symptoms or teratogenic effects (malformations of an embryo or fetus) as adverse effects as well as adverse health effects.

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adverse health effect

A health effect from exposure to air contaminants that may range from relatively mild and temporary (e.g., eye or throat irritation, shortness of breath, or headaches) to permanent and serious conditions (e.g., birth defects, cancer or damage to lungs, nerves, liver, heart, or other organs), and which negatively affects an individual’s health or well-being, or reduces an individual’s ability to respond to an additional environmental challenge.  (EPA 2004)
A change in body function or cell structure that might lead to disease or health problems. (ATSDR 2004)
RELATED TERMS: adverse effect

antagonistic effect

A biologic response to exposure to multiple substances that is less than would be expected if the known effects of the individual substances were added together.  (ATSDR 2004)
RELATED TERMS: additive effect, synergistic effect

antibody

  1. An immunoglobulin molecule that has a specific amino acid sequence by virtue of which it interacts only with the antigen that induced its synthesis in cells of the lymphoid series (especially plasma cells) or with antigen closely related to it. Antibodies are classified according to their ode of action as agglutinins, bacteriolysins, haemolysins, opsonins, precipitins, etc.  (CancerWeb 2005)
  2. An immunoglobulin molecule produced by B lymphoid cells with a specific amino acid sequence evoked in humans or other animals by an antigen (immunogen).  These molecules are characterized by reacting specifically with the antigen in some demonstrable way, antibody and antigen each being defined in terms of the other.  Antibodies may also exist naturally, without being present as a result of the stimulus provided by the introduction of an antigen; antibodies are found in the blood and body fluids, although the basic structure of the molecule consists of two light and two heavy chains, antibodies may also be found as dimers, trimers, or pentamers.  (Stedman 2005)

antigen

  1. Substances which are capable, under appropriate conditions, of inducing a specific immune response and of reacting with the products of that response, that is, with specific antibodies or specifically sensitised T-lymphocytes, or both. Antigens may be soluble substances, such as toxins and foreign proteins, or particulates, such as bacteria and tissue cells; however, only the portion of the protein or polysaccharide molecule known as the antigenic determinant (epitopes) combines with antibody or a specific receptor on a lymphocyte.  (CancerWeb 2005)
  2. Any substance that, as a result of coming in contact with appropriate cells, induces a state of sensitivity and/or immune responsiveness after a latent period (days to weeks) and that reacts in a demonstrable way with antibodies and/or immune cells of the sensitized subject in vivo or in vitro. Modern usage tends to retain the broad meaning of antigen, employing the terms “antigenic determinant” or “determinant group” for the particular chemical group of a molecule that confers antigenic specificity.  (Stedman 2005)

asymptomatic

  1. Without obvious signs or symptoms of disease.  (CancerWEB 2005)

Showing or causing no symptoms (a symptom is any subjective evidence of disease or of a patient’s condition, i.e., such evidence as perceived by the patient; a change in a patient’s condition indicative of some bodily or mental state).  Note that a symptom is different from a sign, which is any objective evidence of a disease, i.e., such evidence that is perceptible to the examining physician, as opposed to the subjective sensations (symptoms) of the patient.  (Dorland 1981)
RELATED TERMS: subclinical infection, carrier

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at-risk population

Any group who may be more susceptible to more serious symptoms or side effects from an illness than the general population.  At-risk groups for foodborne illness include: very young children, pregnant women, the elderly, and people with weakened immune systems.  (FDA 2001)
RELATED TERMS: population at risk, sensitive subgroups, special populations, subpopulation, susceptible subgroups

attenuation

  1. The process by which a compound is reduced in concentration over time, through absorption, adsorption, degradation, dilution, and/or transformation.  Can also be the decrease with distance of sight caused by attenuation of light by particulate pollution.  (EPA 2005b)
  2. Weakening (dilution) of the concentration, as of an antigen in a vaccine.  (MERREA 2005)

bacteremia

  1. The presence of viable bacteria circulating in the bloodstream.  (CancerWeb 2005, USDA 2004)
  2. The presence of bacteria in the blood stream.  (Queensland Health 2005)

biological medium

Any one of the major categories of material within an organism (blood, adipose tissue, breath), through which chemicals can move, be stored, or be biologically, physically, or chemically transformed.  (EPA 2004)
In microbiology, biological medium is support matrix for sustaining microbiological activity or growth, (e.g., liquid broth, agar plates).

biomarker

  1. A specific biochemical in the body which has a particular molecular feature that makes it useful for measuring the progress of disease or the effects of treatment.  (CancerWeb 2005)
  2. Indicators of changes or events in human biological systems.  Biological markers of exposure refer to cellular, biochemical, or molecular measures that are obtained from biological media such as human tissues, cells, or fluids and are indicative of exposure to environmental contaminants.  (NRC 1991)
  3. Indicator of changes or events in biological systems.  Biological markers of exposure refer to cellular, biochemical, analytical, or molecular measures that are obtained from biological media such as tissues, cells, or fluids and are indicative of exposure to an agent.  (IPCS 2004)

chronic

  1. Occurring over a long time (compare with acute).  (ATSDR 2004)
  2. Occurring over a long period of time, either continuously or intermittently; used to describe ongoing effects that develop only after a long exposure, especially when referring to health.  (CRCWQT 2002)

Referring to a health-related state, lasting a long time; referring to exposure, prolonged or long-term, often with specific reference to low intensity.  (MERREA 2005)
RELATED TERMS: contrast with acute

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chronic effect

  1. An effect which occurs as a result of repeated or long term (chronic) exposures.  (EPA 2003)
  2. An adverse effect on a human or animal in which symptoms recur frequently or develop slowly over a long period of time.  (EPA 2005b)

An adverse effect on any living organism in which symptoms develop slowly over a long period of time or recur frequently.  (EPA 2005e)
RELATED TERMS: contrast with acute effect

chronic health effects

  1. An effect which occurs as a result of repeated or long term (chronic) exposures.  (EPA 2003, EPA 2004)
  2. An adverse effect on a human or animal in which symptoms recur frequently or develop slowly over a long period of time.  (EPA 2005b)
  3. Having a persistent, recurring or long-term nature.  (RAIS 2004, SRA 2004)

developmental toxicity

  1. Adverse effects on the developing organism that may result from exposure prior to conception (either parent), during prenatal development, or postnatally until the time of sexual maturation.  The major manifestations of developmental toxicity include death of the developing organism, structural abnormality, altered growth, and functional deficiency.  (EPA 2003)
  2. The potential of an agent to cause abnormal development.  Developmental toxicity generally occurs in a dose-related manner, may result from short-term exposure (including single exposure situations) or from longer term low-level exposure, may be produced by various routes of exposure, and the types of effects may vary depending on the timing of exposure because of a number of critical periods of development for various organs and functional systems.  The four major manifestations of developmental toxicity are death, structural abnormality, altered growth, and functional deficit.  (EPA 2004)

diarrhea

An abnormally frequent discharge of semisolid or fluid fecal matter from the bowel.  (Stedman 2005)

disease

  1. Any deviation from or interruption of the normal structure or function of any part, organ, or system (or combination thereof) of the body that is manifested by a characteristic set of symptoms and signs and whose etiology, pathology, and prognosis may be known or unknown.  (Dorland 1984)
  2. Literally, dis-ease, the opposite of ease, when something is wrong with a bodily function.  The words disease, illness, and sickness are loosely interchangeable, but are better regarded as not synonymous.  Disease is a physiological/psychological dysfunction.  Illness is a subjective state of the person who feels aware of not being well.  Sickness is a state of social dysfunction.  (MERREA 2005)

A general term describing a morbid condition which can be defined by objective, physical signs (e.g., hypertension), subjective symptoms or mental phobias, disorder of function (e.g., biochemical abnormality), or disorders of structure (anatomic or pathological change).  Existence of disease may be questioned in disorder of structure without associated disorder of function.  (SRA 2004)
RELATED TERMS: syndrome

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duration of infectiousness

Refers to the period of time during which a host excretes infectious pathogen.  In this context it does not refer to environmental stability of the pathogen.  (EPA 2005f)

foodborne illness

Infection or intoxication caused by the transfer of microbial or chemical contaminants (substances that spoil or infect) from food or drinking water to a human.  In most cases, the contaminants are bacteria, parasites, or viruses.  (FDA 2001)

gastroenteritis

An inflammation of the stomach and intestine resulting in diarrhoea, with vomiting and cramps when irritation is excessive.  When caused by an infectious agent, it is often associated with fever.  (CRCWQT 2002)

health effect

  1. The clinical manifestation of disease associated with a specific pathogen, including symptomatic and asymptomatic infections, clinical illness, mortality, and sequelae.  (ILSI 2000)
  2. Changes in morphology, physiology growth, development or life span of an organism, which results in impairment of functional capacity or impairment of capacity to compensate for additional stress or increase in susceptibility to the harmful effects or other environmental influences.  (KIWA 2004)
  3. A deviation in the normal function of the human body.  (MERREA 2005, RAIS 2004, SRA 2004)

health endpoint

An observable or measurable biological event used as an index to determine when a deviation in the normal function of the human body occurs.  (EPA 2004)

host

  1. In genetics, the organism, typically a bacterium, into which a gene from another organism is transplanted.  In medicine, an animal infected or parasitized by another organism.  (EPA 2005b)
  2. A person or other living animal, including birds and arthropods, that affords subsistence or lodgment to an infectious agent under natural conditions.  In an epidemiologic context, the host may be a population or a group.  (Last 1988)
  3. A person or other living organism that can be infected by an infectious agent under natural conditions.  (CDC 2005)

illness

A condition marked by pronounced deviation from the normal healthy state.  (Dorland 1981)
RELATED TERMS: subclinical infection

immune status

Immune status is a frequently used term, so it is surprising that definitions were not readily available.  This may be because there are many ways to characterize the human immune system. immune status refers to an individual’s (or population’s) degree of immune system functioning.  Immune markers can include but are not limited to general indicators, such as T-cell count, and myriad specific markers, such as antibodies that confer acquired immunity.  In addition, the general strength and specific abilities of an individual’s immune system fluctuates through time. It can refer to either individual or population based measures of immunity characteristics.

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immunity

The condition of being immune, the protection against infectious disease conferred either by the immune response generated by immunization or previous infection or by other nonimmunologic factors.  (CancerWEB 2005)

immunocompromised

  1. A state of reduced immune responsiveness as a result of inherited defects, infection, administration of immunosuppressive drugs, irradiation, malnutrition, or certain disease processes.  (ILSI 2000)
  2. Individuals with a weakened immune system, making them susceptible to additional infections.  (USDA 2004)

Pregnancy and young or old age are also associated with weakened immune systems.

incubation period

  1. The time from the moment of inoculation (exposure) to the development of the clinical manifestations of a particular infectious disease.  (CancerWEB 2005)

time interval between invasion of the body by an infecting organism and the appearance of the first sign or symptom it causes; in a disease vector, the period between entry of the disease organism and the time at which the vector is capable of transmitting the disease to another human host.  (Stedman 2005)
RELATED TERMS: latency period

individual susceptibility

The marked variability in the manner in which individuals will respond to a given exposure to a toxic agent.  (MERREA 2005, SRA 2004)

infectibility

The host characteristic or state in which the host is capable of being infected.  (MERREA 2005)

infection

  1. Attachment and growth of pathogenic microorganisms, including bacteria, protozoans, viruses, and parasites, on or within the body of a human or animal.  (FDA 2001)
  2. Colonisation by a micro-organism.  (KIWA 2004)
  3. The entry and development or multiplication of an infectious agent in the body of man or animals.  Infection is not synonymous with infectious disease; the result may be unapparent or manifest.  The presence of living infectious agents on exterior surfaces of the body is called “infestation.”  The presence of living infectious agents upon articles of apparel or soiled articles is called contamination.  (MERREA 2005)

An illness or carrier state arising from colonization of foodborne microbial pathogens in the human gastrointestinal tract or other parts of the human body.  Human antibodies that resist these pathogens may cause chronic complications.  (USDA 2004)
RELATED TERMS: contagious

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latency period

  1. The time between first exposure to an agent and manifestation or detection of a health effect of interest.  (EPA 2003)
  2. A period of subclinical or inapparent pathologic changes following exposure, ending with the onset of symptoms of chronic disease.  (CDC 2005)
  3. Period of time from exposure to an agent to the onset of a health effect.  (MERREA 2005, RAIS 2004, SRA 2004)

latent infection

An asymptomatic infection capable of manifesting symptoms under particular circumstances or if activated.  (CancerWeb 2005, Stedman 2005)

nosocomial infection

  1. Pertaining to or originating in the hospital, said of an infection not present or incubating prior to admittance to the hospital, but generally occurring 72 hours after admittance, the term is usually used to refer to patient disease, but hospital personnel may also acquire nosocomial infection.  (CancerWEB 2005)

An infection originating in a medical facility, e.g., occurring in a patient in a hospital or other health care facility in whom the infection was not present or incubating at the time of admission.  Includes infections acquired in the hospital but appearing after discharge; it also includes such infections among staff.  (MERREA 2005)
RELATED TERMS: infection

nutritional status

State of the body in relation to the consumption and utilization of nutrients.  (CancerWEB 2005)

outcome

A term used in risk assessment that refers to an effect or consequence such as disease, illness, injury, birth defect, organ damage, death, etc.  (NYS 1998)

patient isolation

The segregation of patients with communicable or other diseases for a specified time.  Isolation may be strict, in which movement and social contacts are limited; modified, where an effort to control specified aspects of care is made in order to prevent cross infection; or reverse, where the patient is secluded in a controlled or germ-free environment in order to protect him or her from cross infection.  (CancerWeb 2005).

population at risk

  1. A population subgroup that is more likely to be exposed to a chemical, or is more sensitive to the chemical, than is the general population.  (EPA 2005b)

A limited population that may be unique for a specific dose-effect relationship; the uniqueness may be with respect to susceptibility to the effect or with respect to the dose or exposure itself.  (MERREA 2005, RAIS 2004, SRA 2004)
RELATED TERMS: at-risk population, population at risk, sensitive subgroups, special populations, subpopulation, susceptible subgroups

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protective immunity

State of specific resistance to infection and infectious disease resulting from prior exposure to a pathogen and/or pathogen-derived toxins.  (ILSI 2000)
RELATED TERMS: immunity

secondary infection

An infection, usually septic, occurring in a person or animal already suffering from an infection of another nature.  (CancerWeb 2005, Stedman 2005)

sensitive subgroups

Identifiable subsets of the general population that, due to differential exposure or susceptibility, are at greater risk than the general population to the toxic effects of a specific air pollutant (e.g., depending on the pollutant and the exposure circumstances, these may be groups such as subsistence fishers, infants, asthmatics, or the elderly).  (EPA 2004)
RELATED TERMS: at-risk population, population at risk, special populations, subpopulation, susceptible subgroups

sensitivity

  1. The ability of a test to work on people you know have the infection. More precisely TP/(TP+FN), where TP is the number of true positives and FN is the number of false negatives. (Swinton 1999)

Sensitivity of a screening test is the proportion of truly diseased persons in the screened population who are identified as diseased by the screening test.  Sensitivity is a measure of the probability of correctly diagnosing a case, or the probability that any given case will be identified by the test (Syn: true positive rate).  (Last 1983)
RELATED TERMS: specificity

sequelae

Abnormal conditions that arise following the acute phase of a disease.  For example, kidney failure may follow acute E. coli O157:H7 disease.  (USDA 2004)

severity of illness

The degree or extent of clinical disease produced by an infectious microorganism or toxin.  Severity of illness does not necessarily reflect severity of infection.  (ILSI 2000)

severity of infection

The degree or extent to which a microorganism multiplies or develops in a susceptible host.  Severity of infection does not necessarily determine severity of illness.  (ILSI 2000)

special populations

People who might be more sensitive or susceptible to exposure to hazardous substances because of factors such as age, occupation, sex, or behaviors (for example, cigarette smoking).  Children, pregnant women, and older people are often considered special populations.  (ATSDR 2004)
RELATED TERMS: at-risk population, population at risk, sensitive subgroups, subpopulation, susceptible subgroups

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specific immunity

The immune status in which there is an altered reactivity directed solely against the antigenic determinants (infectious agent or other) that stimulated it.  (CancerWEB 2005) 
RELATED TERMS: immunity

subclinical infection

  1. An infection in which symptoms are sufficiently mild or inapparent to escape diagnosis other than by positive confirmation of the ability to transmit the infection or serologically.  (CancerWeb 2005)

Infection associated with no detectable clinical signs but caused by a microorganism capable of producing clinical illness.  Infection may remain subclinical, or signs and symptoms of disease may subsequently become apparent.  (ILSI 2000)
RELATED TERMS: asymptomatic

subpopulation

A subset of the target population that has been identified for a specific purpose, usually requires the ability to estimate an attribute of the subpopulation.  (EPA 2005c)
RELATED TERMS: at-risk population, population at risk, sensitive subgroups, special populations, susceptible subgroups

susceptibility

  1. Increased likelihood of an adverse effect, often discussed in terms of relationship to a factor that can be used to describe a human subpopulation (e.g., life stage, demographic feature, or genetic characteristic).  (EPA 2003, ATSDR 2004)
  2. The extent to which a host is vulnerable to infection by a pathogen, taking into account a host’s intrinsic and/or acquired traits that modify the risk of infection.  (ILSI 2000)

susceptible subgroups

May refer to life stages, for example, children or the elderly, or to other segments of the population, for example, asthmatics or the immune-compromised, but are likely to be somewhat chemical-specific and may not be consistently defined in all cases.  (EPA 2003, ATSDR 2004)
RELATED TERMS: at-risk population, population at risk, sensitive subgroups, special populations,subpopulation

syndrome

  1. A set of signs or a series of events occurring together that often point to a single disease or condition as the cause.  (CancerWeb 2005)
  2. A group of symptoms and signs that tend to appear together and collectively characterize a disorder.  (MERREA 2005)

The aggregate of symptoms and signs associated with any morbid process, and constituting together the picture of the disease.  (Stedman 2005)
RELATED TERMS: disease

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systemic effects

  1. Toxic effects as a result of absorption and distribution of a toxicant to a site distant from its entry point.  (EPA 2003)

Systemic effects are those that require absorption and distribution of the toxicant to a site distant from its entry point, at which point effects are produced.  Most chemicals that produce systemic toxicity do not cause a similar degree of toxicity in all organs, but usually demonstrate major toxicity to one or two organs.  These are referred to as the target organs of toxicity for that chemical.  Systemic effects do not include cancer.  (RAIS 2004)
RELATED TERMS: systemic toxicity

systemic toxicity

SEE: systemic effects

target

Any biological entity that receives an exposure or a dose (e.g., a human, a human population, or a human organ).  (IPCS 2004)

target organ

The biological organ(s) most adversely affected by exposure to a chemical, physical, or biological agent.  (EPA 2003)

target population

The target population is the entire group a researcher is interested in; the group about which the researcher wishes to draw conclusions.  (STEPS 1997)
RELATED TERMS: population

uptake (absorption)

The process by which an agent crosses an absorption barrier (see Dose).  (IPCS 2004)

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5.6   Host Characterization and Health Effect Terms

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acquired immunity

A form of cellular defense which identifies certain foreign substances (antigens) as harmful to the body.  For this reason, the body can acquire resistance to a particular foreign agent.  (CancerWEB 2005)
RELATED TERMS: immunity

active immunity

An organisms resistance to disease or infection, developed because the organisms immune system has produced antibodies after an infection or inoculation.  (CancerWEB 2005)
Resistance developed in response to stimulus by an antigen (infecting agent or vaccine) and usually characterized by the presence of antibody produced by the host.  (MERREA 2005)
RELATED TERMS: immunity

acute

Occurring over a short time (compare with chronic).  (ATSDR 2004)
Referring to a health effect, sudden onset, often brief; sometimes loosely used to mean severe; referring to exposure, brief, intense, or short-term; sometimes specifically referring to a brief exposure of high intensity.  (MERREA 2005)
RELATED TERMS: contrast with chronic

acute effect

  1. Any toxic effect produced with a short period of time following an exposure, for example, minutes to a few days (EPA 2004)
  2. An adverse effect on any living organism in which severe symptoms develop rapidly and often subside after the exposure stops.  (EPA 2005e)
  3. Occurring over a short time.  (ATSDR 2004)
  4. Diseases or responses with short and generally severe course (often due to high pollutant concentrations).  (RAIS 2004, SRA 2004)

adverse effect

  1. A biochemical change, functional impairment, or pathologic lesion that affects the performance of the whole organism, or reduces an organism’s ability to respond to an additional environmental challenge.  (EPA 2003)
    (Adverse ecological effects) Changes considered undesirable because they alter valued structural or functional characteristics of ecosystems or their components.  (EPA 1998a)
  2. Change in morphology, physiology, growth, development, or life span of an organism that results in impairment of functional capacity or impairment of capacity to compensate for additional stress or increase in susceptibility to the harmful effects of other environmental influences.  Decisions on whether or not any effect is adverse require expert judgment.  (WHO 1994)
  3. Change in morphology, physiology, growth, development or lifespan of an organism that results in impairment of functional capacity or impairment of capacity to compensate for additional stress or increase in susceptibility to the harmful effects of other environmental influences.  (ILSI 2001)
  4. Change in the morphology, physiology, growth, development, reproduction or life span of an organism, system, or (sub) population that results in an impairment of functional capacity, an impairment of the capacity to compensate for additional stress, or an increase in susceptibility to other influences.  (IPCS/OECD 2004)
    RELATED TERMS: adverse health effect

Adverse effect is a general term that can be applied more broadly than the effects explicitly stated above.  All adverse health effects can be considered adverse effects, however not all adverse effects are adverse health effects.  Based on the definitions for the two terms, the distinction is whether health related symptoms are experienced.  For example, biochemical changes, pathological lesions, and changes in morphology may be classified as adverse effects even when they are only precursors to an adverse health effect.  Even though the two terms are not identical in meaning it is not unreasonable to classify disease symptoms or teratogenic effects (malformations of an embryo or fetus) as adverse effects as well as adverse health effects.

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adverse health effect

A health effect from exposure to air contaminants that may range from relatively mild and temporary (e.g., eye or throat irritation, shortness of breath, or headaches) to permanent and serious conditions (e.g., birth defects, cancer or damage to lungs, nerves, liver, heart, or other organs), and which negatively affects an individual’s health or well-being, or reduces an individual’s ability to respond to an additional environmental challenge.  (EPA 2004)
A change in body function or cell structure that might lead to disease or health problems. (ATSDR 2004)
RELATED TERMS: adverse effect

antagonistic effect

A biologic response to exposure to multiple substances that is less than would be expected if the known effects of the individual substances were added together.  (ATSDR 2004)
RELATED TERMS: additive effect, synergistic effect

antibody

  1. An immunoglobulin molecule that has a specific amino acid sequence by virtue of which it interacts only with the antigen that induced its synthesis in cells of the lymphoid series (especially plasma cells) or with antigen closely related to it. Antibodies are classified according to their ode of action as agglutinins, bacteriolysins, haemolysins, opsonins, precipitins, etc.  (CancerWeb 2005)
  2. An immunoglobulin molecule produced by B lymphoid cells with a specific amino acid sequence evoked in humans or other animals by an antigen (immunogen).  These molecules are characterized by reacting specifically with the antigen in some demonstrable way, antibody and antigen each being defined in terms of the other.  Antibodies may also exist naturally, without being present as a result of the stimulus provided by the introduction of an antigen; antibodies are found in the blood and body fluids, although the basic structure of the molecule consists of two light and two heavy chains, antibodies may also be found as dimers, trimers, or pentamers.  (Stedman 2005)

antigen

  1. Substances which are capable, under appropriate conditions, of inducing a specific immune response and of reacting with the products of that response, that is, with specific antibodies or specifically sensitised T-lymphocytes, or both. Antigens may be soluble substances, such as toxins and foreign proteins, or particulates, such as bacteria and tissue cells; however, only the portion of the protein or polysaccharide molecule known as the antigenic determinant (epitopes) combines with antibody or a specific receptor on a lymphocyte.  (CancerWeb 2005)
  2. Any substance that, as a result of coming in contact with appropriate cells, induces a state of sensitivity and/or immune responsiveness after a latent period (days to weeks) and that reacts in a demonstrable way with antibodies and/or immune cells of the sensitized subject in vivo or in vitro. Modern usage tends to retain the broad meaning of antigen, employing the terms “antigenic determinant” or “determinant group” for the particular chemical group of a molecule that confers antigenic specificity.  (Stedman 2005)

asymptomatic

  1. Without obvious signs or symptoms of disease.  (CancerWEB 2005)

Showing or causing no symptoms (a symptom is any subjective evidence of disease or of a patient’s condition, i.e., such evidence as perceived by the patient; a change in a patient’s condition indicative of some bodily or mental state).  Note that a symptom is different from a sign, which is any objective evidence of a disease, i.e., such evidence that is perceptible to the examining physician, as opposed to the subjective sensations (symptoms) of the patient.  (Dorland 1981)
RELATED TERMS: subclinical infection, carrier

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at-risk population

Any group who may be more susceptible to more serious symptoms or side effects from an illness than the general population.  At-risk groups for foodborne illness include: very young children, pregnant women, the elderly, and people with weakened immune systems.  (FDA 2001)
RELATED TERMS: population at risk, sensitive subgroups, special populations, subpopulation, susceptible subgroups

attenuation

  1. The process by which a compound is reduced in concentration over time, through absorption, adsorption, degradation, dilution, and/or transformation.  Can also be the decrease with distance of sight caused by attenuation of light by particulate pollution.  (EPA 2005b)
  2. Weakening (dilution) of the concentration, as of an antigen in a vaccine.  (MERREA 2005)

bacteremia

  1. The presence of viable bacteria circulating in the bloodstream.  (CancerWeb 2005, USDA 2004)
  2. The presence of bacteria in the blood stream.  (Queensland Health 2005)

biological medium

Any one of the major categories of material within an organism (blood, adipose tissue, breath), through which chemicals can move, be stored, or be biologically, physically, or chemically transformed.  (EPA 2004)
In microbiology, biological medium is support matrix for sustaining microbiological activity or growth, (e.g., liquid broth, agar plates).

biomarker

  1. A specific biochemical in the body which has a particular molecular feature that makes it useful for measuring the progress of disease or the effects of treatment.  (CancerWeb 2005)
  2. Indicators of changes or events in human biological systems.  Biological markers of exposure refer to cellular, biochemical, or molecular measures that are obtained from biological media such as human tissues, cells, or fluids and are indicative of exposure to environmental contaminants.  (NRC 1991)
  3. Indicator of changes or events in biological systems.  Biological markers of exposure refer to cellular, biochemical, analytical, or molecular measures that are obtained from biological media such as tissues, cells, or fluids and are indicative of exposure to an agent.  (IPCS 2004)

chronic

  1. Occurring over a long time (compare with acute).  (ATSDR 2004)
  2. Occurring over a long period of time, either continuously or intermittently; used to describe ongoing effects that develop only after a long exposure, especially when referring to health.  (CRCWQT 2002)

Referring to a health-related state, lasting a long time; referring to exposure, prolonged or long-term, often with specific reference to low intensity.  (MERREA 2005)
RELATED TERMS: contrast with acute

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chronic effect

  1. An effect which occurs as a result of repeated or long term (chronic) exposures.  (EPA 2003)
  2. An adverse effect on a human or animal in which symptoms recur frequently or develop slowly over a long period of time.  (EPA 2005b)

An adverse effect on any living organism in which symptoms develop slowly over a long period of time or recur frequently.  (EPA 2005e)
RELATED TERMS: contrast with acute effect

chronic health effects

  1. An effect which occurs as a result of repeated or long term (chronic) exposures.  (EPA 2003, EPA 2004)
  2. An adverse effect on a human or animal in which symptoms recur frequently or develop slowly over a long period of time.  (EPA 2005b)
  3. Having a persistent, recurring or long-term nature.  (RAIS 2004, SRA 2004)

developmental toxicity

  1. Adverse effects on the developing organism that may result from exposure prior to conception (either parent), during prenatal development, or postnatally until the time of sexual maturation.  The major manifestations of developmental toxicity include death of the developing organism, structural abnormality, altered growth, and functional deficiency.  (EPA 2003)
  2. The potential of an agent to cause abnormal development.  Developmental toxicity generally occurs in a dose-related manner, may result from short-term exposure (including single exposure situations) or from longer term low-level exposure, may be produced by various routes of exposure, and the types of effects may vary depending on the timing of exposure because of a number of critical periods of development for various organs and functional systems.  The four major manifestations of developmental toxicity are death, structural abnormality, altered growth, and functional deficit.  (EPA 2004)

diarrhea

An abnormally frequent discharge of semisolid or fluid fecal matter from the bowel.  (Stedman 2005)

disease

  1. Any deviation from or interruption of the normal structure or function of any part, organ, or system (or combination thereof) of the body that is manifested by a characteristic set of symptoms and signs and whose etiology, pathology, and prognosis may be known or unknown.  (Dorland 1984)
  2. Literally, dis-ease, the opposite of ease, when something is wrong with a bodily function.  The words disease, illness, and sickness are loosely interchangeable, but are better regarded as not synonymous.  Disease is a physiological/psychological dysfunction.  Illness is a subjective state of the person who feels aware of not being well.  Sickness is a state of social dysfunction.  (MERREA 2005)

A general term describing a morbid condition which can be defined by objective, physical signs (e.g., hypertension), subjective symptoms or mental phobias, disorder of function (e.g., biochemical abnormality), or disorders of structure (anatomic or pathological change).  Existence of disease may be questioned in disorder of structure without associated disorder of function.  (SRA 2004)
RELATED TERMS: syndrome

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duration of infectiousness

Refers to the period of time during which a host excretes infectious pathogen.  In this context it does not refer to environmental stability of the pathogen.  (EPA 2005f)

foodborne illness

Infection or intoxication caused by the transfer of microbial or chemical contaminants (substances that spoil or infect) from food or drinking water to a human.  In most cases, the contaminants are bacteria, parasites, or viruses.  (FDA 2001)

gastroenteritis

An inflammation of the stomach and intestine resulting in diarrhoea, with vomiting and cramps when irritation is excessive.  When caused by an infectious agent, it is often associated with fever.  (CRCWQT 2002)

health effect

  1. The clinical manifestation of disease associated with a specific pathogen, including symptomatic and asymptomatic infections, clinical illness, mortality, and sequelae.  (ILSI 2000)
  2. Changes in morphology, physiology growth, development or life span of an organism, which results in impairment of functional capacity or impairment of capacity to compensate for additional stress or increase in susceptibility to the harmful effects or other environmental influences.  (KIWA 2004)
  3. A deviation in the normal function of the human body.  (MERREA 2005, RAIS 2004, SRA 2004)

health endpoint

An observable or measurable biological event used as an index to determine when a deviation in the normal function of the human body occurs.  (EPA 2004)

host

  1. In genetics, the organism, typically a bacterium, into which a gene from another organism is transplanted.  In medicine, an animal infected or parasitized by another organism.  (EPA 2005b)
  2. A person or other living animal, including birds and arthropods, that affords subsistence or lodgment to an infectious agent under natural conditions.  In an epidemiologic context, the host may be a population or a group.  (Last 1988)
  3. A person or other living organism that can be infected by an infectious agent under natural conditions.  (CDC 2005)

illness

A condition marked by pronounced deviation from the normal healthy state.  (Dorland 1981)
RELATED TERMS: subclinical infection

immune status

Immune status is a frequently used term, so it is surprising that definitions were not readily available.  This may be because there are many ways to characterize the human immune system. immune status refers to an individual’s (or population’s) degree of immune system functioning.  Immune markers can include but are not limited to general indicators, such as T-cell count, and myriad specific markers, such as antibodies that confer acquired immunity.  In addition, the general strength and specific abilities of an individual’s immune system fluctuates through time. It can refer to either individual or population based measures of immunity characteristics.

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immunity

The condition of being immune, the protection against infectious disease conferred either by the immune response generated by immunization or previous infection or by other nonimmunologic factors.  (CancerWEB 2005)

immunocompromised

  1. A state of reduced immune responsiveness as a result of inherited defects, infection, administration of immunosuppressive drugs, irradiation, malnutrition, or certain disease processes.  (ILSI 2000)
  2. Individuals with a weakened immune system, making them susceptible to additional infections.  (USDA 2004)

Pregnancy and young or old age are also associated with weakened immune systems.

incubation period

  1. The time from the moment of inoculation (exposure) to the development of the clinical manifestations of a particular infectious disease.  (CancerWEB 2005)

time interval between invasion of the body by an infecting organism and the appearance of the first sign or symptom it causes; in a disease vector, the period between entry of the disease organism and the time at which the vector is capable of transmitting the disease to another human host.  (Stedman 2005)
RELATED TERMS: latency period

individual susceptibility

The marked variability in the manner in which individuals will respond to a given exposure to a toxic agent.  (MERREA 2005, SRA 2004)

infectibility

The host characteristic or state in which the host is capable of being infected.  (MERREA 2005)

infection

  1. Attachment and growth of pathogenic microorganisms, including bacteria, protozoans, viruses, and parasites, on or within the body of a human or animal.  (FDA 2001)
  2. Colonisation by a micro-organism.  (KIWA 2004)
  3. The entry and development or multiplication of an infectious agent in the body of man or animals.  Infection is not synonymous with infectious disease; the result may be unapparent or manifest.  The presence of living infectious agents on exterior surfaces of the body is called “infestation.”  The presence of living infectious agents upon articles of apparel or soiled articles is called contamination.  (MERREA 2005)

An illness or carrier state arising from colonization of foodborne microbial pathogens in the human gastrointestinal tract or other parts of the human body.  Human antibodies that resist these pathogens may cause chronic complications.  (USDA 2004)
RELATED TERMS: contagious

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latency period

  1. The time between first exposure to an agent and manifestation or detection of a health effect of interest.  (EPA 2003)
  2. A period of subclinical or inapparent pathologic changes following exposure, ending with the onset of symptoms of chronic disease.  (CDC 2005)
  3. Period of time from exposure to an agent to the onset of a health effect.  (MERREA 2005, RAIS 2004, SRA 2004)

latent infection

An asymptomatic infection capable of manifesting symptoms under particular circumstances or if activated.  (CancerWeb 2005, Stedman 2005)

nosocomial infection

  1. Pertaining to or originating in the hospital, said of an infection not present or incubating prior to admittance to the hospital, but generally occurring 72 hours after admittance, the term is usually used to refer to patient disease, but hospital personnel may also acquire nosocomial infection.  (CancerWEB 2005)

An infection originating in a medical facility, e.g., occurring in a patient in a hospital or other health care facility in whom the infection was not present or incubating at the time of admission.  Includes infections acquired in the hospital but appearing after discharge; it also includes such infections among staff.  (MERREA 2005)
RELATED TERMS: infection

nutritional status

State of the body in relation to the consumption and utilization of nutrients.  (CancerWEB 2005)

outcome

A term used in risk assessment that refers to an effect or consequence such as disease, illness, injury, birth defect, organ damage, death, etc.  (NYS 1998)

patient isolation

The segregation of patients with communicable or other diseases for a specified time.  Isolation may be strict, in which movement and social contacts are limited; modified, where an effort to control specified aspects of care is made in order to prevent cross infection; or reverse, where the patient is secluded in a controlled or germ-free environment in order to protect him or her from cross infection.  (CancerWeb 2005).

population at risk

  1. A population subgroup that is more likely to be exposed to a chemical, or is more sensitive to the chemical, than is the general population.  (EPA 2005b)

A limited population that may be unique for a specific dose-effect relationship; the uniqueness may be with respect to susceptibility to the effect or with respect to the dose or exposure itself.  (MERREA 2005, RAIS 2004, SRA 2004)
RELATED TERMS: at-risk population, population at risk, sensitive subgroups, special populations, subpopulation, susceptible subgroups

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protective immunity

State of specific resistance to infection and infectious disease resulting from prior exposure to a pathogen and/or pathogen-derived toxins.  (ILSI 2000)
RELATED TERMS: immunity

secondary infection

An infection, usually septic, occurring in a person or animal already suffering from an infection of another nature.  (CancerWeb 2005, Stedman 2005)

sensitive subgroups

Identifiable subsets of the general population that, due to differential exposure or susceptibility, are at greater risk than the general population to the toxic effects of a specific air pollutant (e.g., depending on the pollutant and the exposure circumstances, these may be groups such as subsistence fishers, infants, asthmatics, or the elderly).  (EPA 2004)
RELATED TERMS: at-risk population, population at risk, special populations, subpopulation, susceptible subgroups

sensitivity

  1. The ability of a test to work on people you know have the infection. More precisely TP/(TP+FN), where TP is the number of true positives and FN is the number of false negatives. (Swinton 1999)

Sensitivity of a screening test is the proportion of truly diseased persons in the screened population who are identified as diseased by the screening test.  Sensitivity is a measure of the probability of correctly diagnosing a case, or the probability that any given case will be identified by the test (Syn: true positive rate).  (Last 1983)
RELATED TERMS: specificity

sequelae

Abnormal conditions that arise following the acute phase of a disease.  For example, kidney failure may follow acute E. coli O157:H7 disease.  (USDA 2004)

severity of illness

The degree or extent of clinical disease produced by an infectious microorganism or toxin.  Severity of illness does not necessarily reflect severity of infection.  (ILSI 2000)

severity of infection

The degree or extent to which a microorganism multiplies or develops in a susceptible host.  Severity of infection does not necessarily determine severity of illness.  (ILSI 2000)

special populations

People who might be more sensitive or susceptible to exposure to hazardous substances because of factors such as age, occupation, sex, or behaviors (for example, cigarette smoking).  Children, pregnant women, and older people are often considered special populations.  (ATSDR 2004)
RELATED TERMS: at-risk population, population at risk, sensitive subgroups, subpopulation, susceptible subgroups

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specific immunity

The immune status in which there is an altered reactivity directed solely against the antigenic determinants (infectious agent or other) that stimulated it.  (CancerWEB 2005) 
RELATED TERMS: immunity

subclinical infection

  1. An infection in which symptoms are sufficiently mild or inapparent to escape diagnosis other than by positive confirmation of the ability to transmit the infection or serologically.  (CancerWeb 2005)

Infection associated with no detectable clinical signs but caused by a microorganism capable of producing clinical illness.  Infection may remain subclinical, or signs and symptoms of disease may subsequently become apparent.  (ILSI 2000)
RELATED TERMS: asymptomatic

subpopulation

A subset of the target population that has been identified for a specific purpose, usually requires the ability to estimate an attribute of the subpopulation.  (EPA 2005c)
RELATED TERMS: at-risk population, population at risk, sensitive subgroups, special populations, susceptible subgroups

susceptibility

  1. Increased likelihood of an adverse effect, often discussed in terms of relationship to a factor that can be used to describe a human subpopulation (e.g., life stage, demographic feature, or genetic characteristic).  (EPA 2003, ATSDR 2004)
  2. The extent to which a host is vulnerable to infection by a pathogen, taking into account a host’s intrinsic and/or acquired traits that modify the risk of infection.  (ILSI 2000)

susceptible subgroups

May refer to life stages, for example, children or the elderly, or to other segments of the population, for example, asthmatics or the immune-compromised, but are likely to be somewhat chemical-specific and may not be consistently defined in all cases.  (EPA 2003, ATSDR 2004)
RELATED TERMS: at-risk population, population at risk, sensitive subgroups, special populations,subpopulation

syndrome

  1. A set of signs or a series of events occurring together that often point to a single disease or condition as the cause.  (CancerWeb 2005)
  2. A group of symptoms and signs that tend to appear together and collectively characterize a disorder.  (MERREA 2005)

The aggregate of symptoms and signs associated with any morbid process, and constituting together the picture of the disease.  (Stedman 2005)
RELATED TERMS: disease

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systemic effects

  1. Toxic effects as a result of absorption and distribution of a toxicant to a site distant from its entry point.  (EPA 2003)

Systemic effects are those that require absorption and distribution of the toxicant to a site distant from its entry point, at which point effects are produced.  Most chemicals that produce systemic toxicity do not cause a similar degree of toxicity in all organs, but usually demonstrate major toxicity to one or two organs.  These are referred to as the target organs of toxicity for that chemical.  Systemic effects do not include cancer.  (RAIS 2004)
RELATED TERMS: systemic toxicity

systemic toxicity

SEE: systemic effects

target

Any biological entity that receives an exposure or a dose (e.g., a human, a human population, or a human organ).  (IPCS 2004)

target organ

The biological organ(s) most adversely affected by exposure to a chemical, physical, or biological agent.  (EPA 2003)

target population

The target population is the entire group a researcher is interested in; the group about which the researcher wishes to draw conclusions.  (STEPS 1997)
RELATED TERMS: population

uptake (absorption)

The process by which an agent crosses an absorption barrier (see Dose).  (IPCS 2004)

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