Toxicology

Question 1

Hippocrates (400 B.C.)

Answer 1

*First to describe relationship between work and illness

First real discussions on controlling absorption of compounds

Question 2

Bernardino Ramazzini (1633-1714)

Answer 2

His book outlined health hazards and other agents in the work place

Question 3

Early Aviation Hazards

Answer 3

First fuel used Caster Oil mix for lubrication. Aviators wore long scarves to wipe off spray - ingesting caused severe diarrhea.

Question 4

*Types of hazards

Answer 4

Physical - result form energy and matter - interaction of two things

Biological - cause illness due to infectious properties

Chemical - amount/exposure/ dose determines reaction (water in large quantities; 100% oxygen in hyperbolic chamber)

Occupational - anything capable of causing safety effect

Question 5

Exposure time

Answer 5

Acute - short term, sudden exposure (can incapacitate - cabin leaks)

Chronic - longer term exposure, does not necessarily cause immediate health effect (ground support - fuel)

Question 6

Threshold Limit Value (TLV)

Answer 6

Concentration of chemical that will produce no effects when exposed for 8 hour periods

Question 7

Short Term Exposure Limits (TLV-STEL)

Answer 7

Concentration of chemicals allowed for exposure of 15 min.

Question 8

Ceiling Concentration (TLV-CL)

Answer 8

Concentration never to be exceeded during work day

Question 9

*Toxicology Principals

Answer 9

**Time and dosage - longer/larger dose increases effects

Route of entry (inhalation [most likely], absorption, inhalation)

Ratio of retention and excretion

Physiological effects - metabolism, body fat, genetics

Physiochemical - biochem process of detoxifying chemicals

Environmental - atm pressure (fumes), temperature, humidity

Question 10

Toxic AV substances

Answer 10

Aviation fuels - mainly vapor hazard

Army engines us JP-8 - kerosene, 100*F flash-point

Question 11

AV fuel acute exposure

Answer 11

Neurological - lightheaded; confusion; fatigue; slurred speech; impaired psychomotor

Skin - chemical burns; irritation

Gastrointestinal - nausea; vomit; easy mouth absorption

Cardiac/resp. - irregular HR; respiratory failure; coughing; chocking

Question 12

Carbon Monoxide

Answer 12

Most common and toxic AV substance

0-10% - no effect
10-20% - shortness of breath
20-30% - extreme shortness breath, minor headache
30-40% - pronounced headache, impaired judgement
40-60% - disorientation, fainting
60-80% - unconsciousness, respiratory failure
80-100% - immediate death

Question 13

Solvents/degreasers

Answer 13

Organic bases to dissolve petroleum products

ethyl, cyante base words

Question 14

Lubricants

Answer 14

When exposed to hot surfaces, inhalation hazard and symptoms like carbon monoxide

Skin dermatitis reaction

Question 15

Hydraulic fluids

Answer 15

High pressure leaks can mist cockpit - impairs vision, can pool, and irritates lungs

Question 16

Fire extinguishers

Answer 16

*Threat in enclosed environment

Halon type - liquified compressed gas, non-toxic unless used in enclosed space - decomposes to acids with high heat!

CO2 type - safe, large quantities needed for harm - 2-5% can cause drowsiness/headache, 10% can cause collapse/death

Aquious film forming foam - like dawn dish soap; is a skin irritant.

Question 17

Composites/plastics

Answer 17

Composed of:

Fibers - include graphite, boron, kevlar, fiberglass; primary hazard is inhalation (like asbestos)

Resins - include epoxy, phenol, polyurethane, amino acids; hazard on thermal release inhalation

Question 18

Plastics

Answer 18

When burned - release cyanide, Florine gas, and phosgene

Question 19

Protection Measures

Answer 19

Individual - prevent contamination, wash hands, wear PPE, pay attention to symptoms

Cockpit - be aware for potential exposure, smoke/fumes are a serious matter; take immediate action (recognize, ventilate, descend, land, evacuate, seek medical)

Question 20

Route of Entry

Answer 20

Route of entry - inhalation (most common), absorption, ingestion

Question 21

Ratio of retention and excretion

Answer 21

Ratio of retention and excretion - how long toxin stays in body, how quickly KIDNEYS and LIVER (usually) can get rid of it

Question 22

Physiological

Answer 22

Physiological effects - metabolism (age, meds), body fat, genetics (ethnicity, sex)

Question 23

Physiochemical

Answer 23

Physiochemical - biochemical process of ridding chemicals (kidneys, liver)

Question 24

Environmental

Answer 24

Environmental - Atmospheric pressure (fumes)
Temperature (toxin worse in high temp)
Humidity (chemicals thru hot/wet skin)