U 5.1 : INTRO TO TOXICOLOGY Flashcards
Event in History
Rapid development of Industrialization and the use of fossil fuels
Great Smog of London
Event in History
A lot of the people developed respiratory illnesses
Great Smog of London
Event in History
Mercurial pollution in water sources
Minamata Disease
People had neurological
manifestations due to methyl mercury that has been implicated
Minamata Disease
Event in History
Nuclear reactor, radiation leak
Chernobyl
T/F Exposure to chemicals may be through the environment (air, water, soil, food) and/or occupational.
T
T/F Most common chemicals are used in households, personal care and
consumer products; agriculture and industry.
T
Toxicology Effects (3)
- Dose
- Duration of Exposure
- Vulnerability of Individuals
Toxicology can affect (3)
- CNS
- Liver and kidneys
- Reproductive system
T/F Signs and symptoms in toxicology are always specific
F; non-specific
T/F Diseases caused by toxicology has no treatment available.
F; treatment available
Deals with the effects of chemicals found in the workplace
Occupational Toxicology
Things to identify in occupational toxicology
- Agents of concern
- Acute and chronic diseases
- Conditions for safe use
- Preventive measures
- Treatment
- Surveillance
provide “safe” chemical exposure limits for workers
Occupational Safety and Health Administration (OSHA)
standards for specific materials of particularly serious toxicity
Permissible Exposure Limits (PELs)
Environmental Toxicology is also known as
ecotoxicology
Deals with the deleterious impact of chemical pollutants in the environment, on living organisms.
Environmental Toxicology
T/F Environmental toxicology deals with toxic effects of chemical and physical agent on populations and communities of non-living organisms within defined ecosystems.
F; living organisms
Environmental toxicology deals with
Transfer pathways of those agents & interactions with the environment
Concerned with the impact on populations of living organisms or on ecosystems and is affected by Air, Soil or Water pollution
Environmental Toxicology`
Ability of chemical agent to cause injury/disease in a given situation or setting
Hazard
Expected frequency of the of the occurrence of an
undesirable effect arising from exposure to a chemical or physical agent
Risk
Likelihood that a hazard will cause harm
Risk
Routes of Exposure for Industrial
Industrial: Inhalational > Transdermal Route > Oral
Water and Soil pollutants are absorbed through
inhalational, ingestion or transdermal
Most common in the household setting is the oral route
Ingestion
An exposure to a toxic substance that is absorbed by the target human or animal results in a dose.
Quantity, Duration & Intensity of Exposure
Single exposure or multiple exposure over a brief period of time
Acute Exposure
Single or multiple exposure over a longer period of time
Chronic Exposure
Degradability, bioaccumulation, and transport and biomagnification
Environmental considerations
Environmental Considerations
Chemicals that exhibit environmental persistence and can accumulate
Poorly degraded chemicals
Environmental Considerations
Lipophilic substances: organochlorine pesticides bioaccumulate in body fat ->
- endocrine disruption
- neurological disorders
- carcinogenesis/cancer formation
Environmental Considerations
Methyl mercury discharges ->
neurotoxic (Ex. Metal, mining)
Environmental Considerations
entails specific or only one organism or
biologic system
Bioaccumulation
Environmental Considerations
entails several biological systems or organisms to occur
Biomagnification
Environmental Considerations
Concentrates the chemical in organisms higher on the food chain. (magnifies)
Biomagnification
T/F The pollutants that have the widest environmental impact are poorly degradable; are relatively mobile in air, water, and soil; exhibit bioaccumulation; and also exhibit biomagnification.
T
Air Pollutants
- Colorless, tasteless, odorless and nonirritating gas
- Byproduct of incomplete combustion
- from gas stoves; generators and other gasoline powered equipment; automobile exhaust and tobacco smoke
Carbon Monoxide (CO)
Air Pollutants
- Easily absorbed through the lungs
- Exposure may be acute or chronic
- Has teratogenic potential
Carbon Monoxide (CO)
Air Pollutants
a silent killer
Carbon Monoxide (CO)
Air Pollutants
combines tightly but reversibly with the oxygen binding
site of hemoglobin (Hb) producing Carboxyhemoglobin
CO
Air Pollutants
produced when CO combines tightly but reversibly with the oxygen binding
site of hemoglobin (Hb
Carboxyhemoglobin
Air Pollutants (CO)
Organs with the highest oxygen demand are most seriously affected
Brain, Heart and Kidneys
Air Pollutants
Clinical Effects include symptoms of hypoxia, psychomotor impairment, headache and tightness in temporal area
Carbon Monoxide (CO)
Air Pollutants
Clinical Effects include confusion and loss of visual acuity, tachycardia, tachypnea, syncope, and coma, deep coma, convulsions, shock and respiratory failure
Carbon Monoxide (CO)
Air Pollutants
- Colorless irritant gas
- Gas at the Great Smog of London
- Generated primarily by the
combustion of sulfur containing fossil
fuel
Sulfur Dioxide (SO2)
Air Pollutants
High solubility of SO2 in moist membranes forms
sulfurous acid
Air Pollutants
Severe irritant on the eyes, mucous membranes, respiratory tract and skin
sulfurous acid
Air Pollutants
T/F 90% of inhaled form of SO2 is absorbed in the Lower Respiratory tract causing Acute Irritant Asthma
F; Upper Respiratory Tract
Air Pollutants
Clinical Effects include Eye, nose and throat irritation, reflex bronchoconstriction and increased bronchial secretions
Sulfur Dioxide (SO2)
Air Pollutants
Treatment is supportive, non-specific
Sulfur Dioxide (SO2), Nitrogen Oxides (NO2)
Air Pollutants
- May initiate or exacerbate Bronchial Asthma
- Delayed-onset pulmonary edema
Sulfur Dioxide (SO2)
Air Pollutants
Brownish irritant gas associated with fires
Nitrogen Oxides (NO2)
Air Pollutants
Mostly in alveoli which it damages it by causing the surfactant to be decreased
Nitrogen Oxides (NO2)