Toxicology

Question 1

Define toxicology

Answer 1

Study of quantitative effects of chemical on biological tissue

Question 2

Define toxic

Answer 2

Harmful with regard to effects of chemicals

Question 3

Measures of exposure

Answer 3

(1) Length of exposure
(2) Frequency of exposure
(3) Route of exposure
(4) Dose delivered
(5) Physical/chemical form

Question 4

Acute Vs. Chronic

Answer 4

Acute: single event with rapid absorption.
Chronic: dose delivered over some period of time.

Question 5

Local effect Vs. Systemic effect

Answer 5

Local: effect may be at site of exposure.
Systemic: toxin may be transported to some distant sight then exert its toxic effect.

Question 6

Elimination of toxic

Answer 6

(1) Biotransformation (metabolism): change to a less toxic form in preparation for elimination. Sometimes it leads to a more toxic form.
(2) Excretion:

Question 7

Routes for toxic materials: Respiratory system

Answer 7

Respiratory system: important route of entry for toxic materials.

Question 8

Routes for toxic materials: Pulmonary

Answer 8

Pulmonary inflammation: URT, bronchi, lungs. Causes pneumoconiosis which is dust fibers on the lung

Question 9

Routes for toxic materials: Kidneys

Answer 9

Kidneys: nephrotoxins from heavy metals such as Pb, Hg, Cd, and Cr. Results in tubular damage that may lead to blockage.

Question 10

Routes for toxic materials: Liver

Answer 10

Liver (hepatic): receives nearly all GI blood. Hepatotoxins include chlorinated HC’s: CCl4, and CHCl3. Alcohol, acetaminophen, potentiation: CCl4+EtOH

Question 11

Routes for toxic materials: Blood

Answer 11

Hematopoietic: damage to RBCs causes impaired O2 transport.
Arsine: direct hemolytic effects

Question 12

Gases and vapor

Answer 12

Asphyxiants: simple includes N2, N2O2, CO2, H2, He, CH4
Chemical: CO, Cn, H2S

Question 13

Solvent toxicity

Answer 13

Incidental exposures everywhere. Effects include irritation, nuisance, narcosis, dermatitis, cancer.
Aliphatic HC’s and alcohol

Question 14

Metal toxicity

Answer 14

Disease potential from accumulation.
Routes of entry include inhalation, topical, ingestion.
Organ of toxicity: kidneys and is carcinogenic potential

Question 15

Pesticides

Answer 15

(1) Organophosphate:
(2) Carbamates
(3) Organochlorine
(4) Warfrin (rat poison): anticoagulant

Question 16

Carcinogen

Answer 16

Normal cells to neoplastic cells. Neoplastic cells to neoplasm which causes cells to reproduce.
Non-carcinogen such as asbestos causes lung cancer
Promotion is the increased development of neoplasm. From croton oil.

Question 17

Teratogens

Answer 17

Defect of fetal development. 1.5% of congenital defects are from drugs or chemicals.