Term
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Definition
1. determine risks we are exposed to
2. understand how to manage those risks |
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Term
| Key environmental chemicals of greatest concern |
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Definition
1. anthropogenic organic compounds
2. unsuspecting environmental contaminants |
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Term
| anthropogenic organic compounds |
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Definition
1. pesticides
2. solvents
3. fuel products
4. by-products of various industrial products |
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Term
| unsuspecting environmental contaminants |
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Definition
1. reproductive hormones
2. birth control pills, steroids, antibiotics, metabolites |
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Term
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Definition
--naturally occurring (released into water bodies)
--Uses: insecticides, alloying agents, wood preservatives
--Health effects: GI effects, cardiovascular disease, diabetes, reproductive effects, carcinogenic |
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Term
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Definition
--known human carcinogen
--Uses: cigarette filters, wine filters, hair dryers, brake linings, cement pipes, floor tiles
--Health effects: all related to inhalation of microscopic fibers, asbestosis, mesothelioma |
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Term
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Definition
--Uses: water systems, gasoline, automobile batteries, paints
--Health effects: nausea and irritability (at low levels), brain damage (at high levels)
--Major routes of exposure: inhalation and ingestion |
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Term
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Definition
--Nervous system toxin
--Uses: thermometers, manometers, medicines, fungicides, combustion of fossil fuels, waste incineration, industrial processes
--present in both organic and inorganic forms
--the form of mercury and the manner of human exposure determine the nature of health effects |
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Term
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Definition
--chlorinated hydrocarbons (PCBs, DDT)
--Uses: electric transformers, pesticides, insecticides
--lipophilic and persistent
--endocrine disruptors, carcinogens, reproductive and developmental disorders |
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Term
| Degree of hazards posed by the contacted substance will generally be dependent upon |
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Definition
--physical form and chemical composition
--quantities contacted
--reactivity
--toxicity effects
--local conditions and environmental settings (temperature, humidity, light) |
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Term
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Definition
--have biological effects that are different in nature and degree when compared to those of individual substances acting alone
--additive (sum of individual effects)
--synergistic (the fact is greater than the sum of individual effects)
--antagonistic (active substance decreases the effect of another active substance)
--potentiation (inactive or neutral substance enhances the action of an active substance) |
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Term
| classification of chemical toxicity |
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Definition
--acute vs. chronic
--local vs. symptomatic
--immediate vs. delayed |
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Term
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Definition
| involves the sudden onset of symptoms that lasts for a short period of time |
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Term
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Definition
| results in symptoms that are of long continuous duration |
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Term
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Definition
| occurs when the symptoms resulting from exposure to a toxicant are restricted or limited to the site of initial exposure |
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Term
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Definition
| occurs when the adverse effects occur at sites far removed from the initial site of exposure |
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Term
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Definition
results when symptoms occur rapidly following the exposure of an organism to a toxicant
--delayed toxicity generally results long after exposure and therefore sometimes adds to the difficulty in establishing a cause-and-effect relationship |
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Term
| time depenent toxicant behavior |
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Definition
time dependent behavior of the toxicant is related to its absorption, distribution, storage, biotransformation, and elimination
--toxicokinetics and toxicokinetics are important areas of study in this respect |
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Term
| Factors influencing chemical toxicity to humans |
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Definition
--nature of toxic chemical (physical and chemical properties, mechanism of action)
--exposure characteristics (dose, route of exposure)
--individual susceptibility (age, gender)
--hazard controls (safe work practices, source reduction)
--medical intervention (screening, treatment) |
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Term
| distribution and storage of toxicants in the human body |
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Definition
| exposure --> absorption --> distribution --> storage |
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Term
| Factors affecting the distribution of toxicants to tissues in the human body |
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Definition
--physical/chemical properties/characteristics of the toxicant
--concentration gradient (blood/tissue)
--volume of blood flowing through a specific tissue or organ
--affinity of the toxicants for specific tissues
--structural barriers to slow down the entrance of the toxicant |
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Term
| Scope of chemical hazard problems |
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Definition
| potency + exposure = toxicity |
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Term
| "The dose makes the poison" |
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Definition
Ex: Metals
--essential for many cellular functions and evolutionary development
--concentrations that are too high or too low can cause problems
--distinctions between therapeutic and toxic properties (i.e. concentrations) |
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Term
| Need for public health risk assessment |
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Definition
--some risks are tolerable
--we need a tool to systematically manage risks and develop policy
--clean-up levels
--acceptable risk/non-acceptable risks |
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Term
| General objectives of risk management programs |
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Definition
1. Does a hazard exist and can humans contact it?
2. Estimate the potential threat to public health
3. Is immediate response needed?
4. Determine remedies and/or corrective action
5. Informational needs of community at risk (health, safety, reduced exposure, etc.) |
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Term
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Definition
--Differences in policy (regional, national, global)
--Many times risk assessment is carried out as part of a legislative process (Potential problems with this: motives, extent of risk reduction, parties affected) |
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