Toxicology

Question 1

Concerned with the deleterious effects of these chemical agents on all living systems

Answer 1

TOXICOLOGY

Question 2

Primarily concerned with adverse effects in humans resulting from exposure to drugs and other chemicals as well as the demonstration of safety or hazard associated with their use

Answer 2

TOXICOLOGY

Question 3

 deals with the chemicals found in the workplace.

Answer 3

OCCUPATIONAL TOXICOLOGY

Question 4

 define and carry out programs for the surveillance of exposed workers and the environment in which they work

Answer 4

OCCUPATIONAL TOXICOLOGY

Question 5

deals with the potentially deleterious impact of chemicals, present as pollutants of the environment, on living organisms

Answer 5

ENVIRONEMENTAL TOXICOLOGY

Question 6

concerned with the toxic effects of chemical and physical agents on populations and communities of living organisms within defined ecosystems

Answer 6

ECOTOXICOLOGY

Question 7

includes the transfer pathways of those agents and their interactions with the environment.

Answer 7

ECOTOXICOLOGY

Question 8

ability of a chemical agent to cause injury in a given situation or setting; the conditions of use and exposure are the primary considerations.

Answer 8

Hazard

Question 9

often a description based on subjective estimates (subjective injury) rather than objective evaluation

Answer 9

Hazards

Question 10

expected frequency of the occurrence of an undesirable effect arising from exposure to a chemical or physical agent

Answer 10

Risks

Question 11

Estimation of risk makes use of ?

Answer 11

dose-response data

Question 12

A single exposure—or multiple exposures occurring over a brief period from seconds to 1 or 2 days

Answer 12

Acute exposure

Question 13

Multiple exposures continuing over a longer period of time

Answer 13

Chronic exposure

Question 14

If the intake of a long-lasting contaminant by an organism exceeds the latter’s ability to metabolize or excrete the substance, the chemical accumulates within the tissues of the organism.

Answer 14

Bioaccumulation

Question 15

Although the concentration of a contaminant may be virtually undetectable in water, it may be magnified hundreds or thousands of times as the contaminant passes up the food chain

Answer 15

Biomagnification

Question 16

colorless, tasteless, odorless, and nonirritating gas, a byproduct of incomplete combustion

Answer 16

Carbon monoxide

Question 17

Threshold limit value of Carbon monoxide

Answer 17

25 ppm

Question 18

MOA of CO toxicity

Answer 18

• formation of Carboxyhemoglobin (220x Oxygen affinity to Hgb)
• interferes with the dissociation of oxygen to remaining oxyhemoglobin

Question 19

Most affected organs of CO poisoning:

Answer 19

Heart and Brain

Question 20

Treatment for CO poisoning

Answer 20

Hyperbaric O2 (2-3 atm)

Question 21

colorless, irritant gas generated primarily by the combustion of sulfur-containing fossil fuels

Answer 21

Sulfur Dioxide

Question 22

Threshold Limit Value of Sulfur dioxide

Answer 22

2 ppm

Question 23

MOA of Sulfur Dioxide Poisoning:

Answer 23

• Mucus membrane irritant (sulfurous acid)
• causes bronchial constriction
• asthmatics are sensitive

Question 24

clinical feature of severe exposure of Sulfur dioxide poisoning

Answer 24

Delayed-onset Pulmonary edema

Question 25

a brownish irritant gas sometimes associated with fires

Answer 25

NITROGEN OXIDES

Question 26

exposure of farmers to NO₂ in the confines of a silo

Answer 26

Silo-Filler’s Disease

Question 27

MOA of NO₂ poisoning

Answer 27

* Relatively insoluble deep lung irritant capable of producing pulmonary edema * primarily targets type 1 alveolar cells

Question 28

Drug therapy for NO₂ poisoning

Answer 28

bronchodilators, sedatives, and antibiotics

Question 29

Threshold Limit Value of NO₂

Answer 29

3 ppm

Question 30

bluish irritant gas and an important absorbent of ultraviolet light

Answer 30

Ozone

Question 31

Clinical Features of Ozone Poisoning

Answer 31

* upper respiratory tract irritation * Pulmonary edema

Question 32

Threshold Limit Value of Ozone

Answer 32

0.05 ppm

Question 33

Air Pollutants

Answer 33

* CO * SO₂ * NO₂ * O₃

Question 34

Solvents

Answer 34

* Halogenated Alipathic Hydrocarbons * **CCl_{4 [5ppm]}** * **CHCl_{3 [10 ppm]}** * **C₂HCl₃** (trichlorethylene) [50 ppm] * **C₂Cl₄** (tetrachlorethylene) [25 ppm] * **C₂H₃Cl₃** (Trichlorethane or methyl chloroform) [350 ppm] * Aromatic Hydrocarbons * Benzene [0.5 ppm] * Toluene [50 ppm] * Xylene [100 ppm]

Question 35

Clinical effects of Halogenated Aliphatic HC

Answer 35

central nervous system depression, liver injury, kidney injury, cardiotoxicity.

Question 36

Clinical effects of Benzene

Answer 36

* Acute: epression of the central nervous system * Chronic: bone marrow injury * high level: Leukema * low level: Myelotoxic

Question 37

a central nervous system depressant and a skin and eye irritant. It is also fetotoxic.

Answer 37

Toluene (Methylbenzene)

Question 38

4 major groups of pesticides

Answer 38

* Organochlorine * Organophosphorous * Carbamates * Botanical

Question 39

Organochlorine pesticides

Answer 39

* DDT (Chlorophenothane) * Benzene hexachlorides (Lindane) * Cyclodienes (Aldrin) * Toxaphenes

Question 40

MOA of Organochlorine Pesticides

Answer 40

* interfere with inactivation of the sodium channel * cause rapid repetitive firing in most neuron * enhances the excitability of neurons (CNS stimulation)

Question 41

Organophosphorous pesticides

Answer 41

* Malathion * Parathion (6) * Methyl-parathion (5) * Trichlorfon * Diazinon * Azinphos-methyl (5)

Question 42

MOA of Organophosphorous pesticides

Answer 42

* inhibition of acetylcholinesterase through phosphorylation of the esteratic site

Question 43

Treatment for Organophosphate poisoning

Answer 43

* Atropine Sulfate * Pralidoxime * Diacetyl monoxime

Question 44

Carbamates pesticides

Answer 44

* Carbofuran * Isolan * Propoxur (Baygon) * Pyrolan * Zectran * Aldicarb (6)

Question 45

MOA of Carbamate poisoning

Answer 45

Inhibits acetylcholinesterase by carbamoylation of the esteratic site

Question 46

Botanical Pesticides

Answer 46

* Nicotine * Rotenone * Pyrethrum

Question 47

eacts with the acetylcholine receptor of the postsynaptic membrane (sympathetic and parasympathetic ganglia, neuromuscular junction) resulting in depolarization of the membrane

Answer 47

Nicotine

Question 48

Symptoms of Rotenone Ingestion

Answer 48

gastrointestinal irritation, conjunctivitis, dermatitis, pharyngitis, and rhinitis

Question 49

cause irritant asthma and, potentially, reactive airways dysfunction syndrome (RADS) and even anaphylaxis

Answer 49

Pyrethrum

Question 50

for aircraft disinfection

Answer 50

Pyrethrum

Question 51

major site of toxic action is the central nervous system; excitation, convulsions, and tetanic paralysis can occur

Answer 51

Pyrethrum

Question 52

Treatment for Pyrethrum poisoning

Answer 52

* Ivermectin * Pentobarbital * Mephenesin

Question 53

Herbicides

Answer 53

* Chlorophenoxy herbicides * Bipyridyl herbicides * Polychlorinated biphenyls * Glyphosphate

Question 54

toxicologic profile for chlorophenoxy hebicides is complicated by the presence of

Answer 54

chemical contaminants (**dioxins**)

Question 56

is the most important agent of BIPYRIDYL HERBICIDES

Answer 56

Paraquat

Question 57

Clinical features of Paraquats

Answer 57

lung edema, alveolitis, and progressive fibrosis

Question 58

inhibits superoxide dismutase

Answer 58

Paraquats

Question 59

Treatment for Paraquat poisoning

Answer 59

* Gastric lavage * Cathartics * Adsorbents

Question 60

cooking oil contamination with PCB-containing transfer medium

Answer 60

Yusho disease

Question 61

is now the most widely used herbicide in the world

Answer 61

Glyphosate (N-[phosphonomethyl] glycine