study guide need by tomorrow afternoon

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 3 elements of industrial hygiene

 Multidisciplinary

 Ultimate goal of industrial hygiene

 IH Contributors

 Agricola

 Paracelsus

 Ramazzini

 Pott

 Hamilton

 IH Organizations

 Elements of an IH Program

 Anticipation/recognition of health hazards

 Physical

 Chemical

 Biological

 Ergonomic

 Evaluation of health hazards

 Control of health hazards

 Recordkeeping

 Employee training

 Program review

Walkthrough Survey

 Elements of an IH Program

 Anticipation/recognition of health hazards

 Evaluation of health hazards

 Instrumentation

 Occupational exposure limits

 Control of health hazards

 Engineering

 Administrative

 Personal protective equipment

 Recordkeeping

 Employee training

 Program review

EHST 3700/3701:

Industrial Hygiene

 To explain the dose-response relationship and

the concept of threshold dose

 To discuss how toxins enter the body and are

transported to different organs and tissues

 To describe the types of toxic effects

resulting from substance exposure

 To describe how toxins are altered,

detoxified, and eliminated from the body

 To enumerate different classes of toxins

 Definition of Toxicology

 Dose-Response Relationship

 Indicators of Relative Toxicity

 Routes of Exposure

 Distribution of Toxins

 Biotransformation of Toxins

 Excretion of Toxins

 Classes of Toxins

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 The study of harmful interactions between

chemicals and living organisms

 Science of poisons

 Importance in industrial hygiene?

 OSHA Hazard Communication Standard

Dose

R e sp

o n se

Threshold Dose

 Dose

 The amount of a

substance

administered

 Response

 Effect or effects of

a substance

 Positive:

therapeutic drug

dosage

 Negative:

respiratory tract

irritation

 Threshold dose

 Dose level below

which the adverse

effects of a

substance are not

expressed by the

exposed

population

 No observed

adverse effect

level (NOAEL)

 No effect level

(NEL) Dose

R e sp

o n se

Threshold Dose Dose

R e sp

o n se

Threshold Dose

Dose

R e sp

o n se

Dose

R e sp

o n se

Dose

R e sp

o n se

A B

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 Toxicity: a substance’ ability to cause harm

or adversely affect an organism

 LD50 (lethal dose)

 Dose of a substance needed to produce death in

50% of the exposed population

 LC50 (lethal concentration)

 Concentration of a substance needed to produce

death in 50% of the exposed population

5 mice 10 mice

Death

 ED50 (effective dose)

 Dose of a substance needed to produce

effectiveness in 50% of the exposed

population

 EC50 (effective concentration)

 Concentration of a substance needed to

produce effectiveness in 50% of the

exposed population

5 cured mice 10 sick mice

Agent LD50 (mg/kg)

Ethyl alcohol 10,000

Sodium chloride 4,000

Morphine sulfate 900

Strychinine sulfate 2

Nicotine 1

Hemicholinium-3 0.2

Dioxin (TCDD) 0.001

Botulinum toxin 0.00001

 Acute effects

 Associated with a short duration of

exposure to a high level of dose

 Chronic effects

 Associated with a longer duration of

exposure to a relatively low level or dose;

carcinogenicity

 Subacute effects

 Associated with exposures or doses that are

below LD50 but still high enough to cause a

toxic response

Toxicity

Classification

LD50

Oral mg/kg

LD50

Inhalation

mg/kg

LD50

Skin mg/kg

Supertoxic <5 <250 <250

Extremely

toxic

5–50 250-1,000 250-1,000

Very toxic 50-500 1,000-10,000 1,000-3,000

Moderately

toxic

500-5,000 10,000-30,000 3,000-10,000

Slightly toxic >5,000 >30,000 >10,000

Route of

Administration

Pentobarbital1

LD50 mg/kg

Procaine1

LD50 mg/kg

DFP2

LD50 mg/kg

Oral 280 500 4.0

Subcutaneous 130 800 1.0

Intramuscular 124 630 0.9

Intraperitoneal 130 230 1.0

Intravenous 80 45 0.3

1 Mouse toxicity data 2 Di-isopropylfluoro phosphate; rabbit toxicity data

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Animal tests are not

designed to prove that a

substance is “safe”.

Animal tests are

used to determine

the toxic effects

that a substance

will produce.

Species Route of

Administration

LD50

Rat Oral 10 mg/kg

Rat Intravenous 6.6 mg/kg

Mouse Oral 117 mg/kg

Mouse Intravenous 87 mg/kg

Dog Oral 1,200 mg/kg

Dog Intravenous 51 mg/kg

 Provides a wide margin between the

lowest anticipated human exposures and

the lowest levels of exposures tested on

animals

Animal data are

extrapolated with

caution to ensure

conservation

application of test

data between

species.

 Descriptive

 Group with similar symptoms  common

exposure

 Cohort

 Prospective: Group with common exposure

 followed through time  disease

 Retrospective: Group with the disease 

back through time  common exposure

Absorption

Distribution

Metabolism

Excretion

 Inhalation

 Ingestion

 Skin absorption

 Injection

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a Liver

b Stomach

c Duodenum

d Ileum

e Colon

f Longitudinal

section of the ileum

g Detail of fold

h,i Circular muscles

j Serosal membrane

k Detail of villi

m Microvilli

 Filtration

 Diffusion

 Active transport

 Phagocytosis

1. Compound must be

fat-soluble.

2. Compound must not

be ionized.

3. There must be a

concentration

gradient across the

cell membrane.

Facilitated diffusion

needs a specific carrier

molecule on the cell

membrane.

 Active transport

 Energy is spent by the

cell

 Chemical reaction or

carrier molecule

 Phagocytosis

 Engulfing of a

molecule by the cell

membrane

 Absorption of solid

materials

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 The process by which these materials are

chemically altered to make them easier to

eliminate

 More water-soluble

 Increased size and weight

Acetaminophen

Toxic

Metabolite

Liver Damage

Blood

Bile

The functions of the liver

make it vulnerable as a

target organ.

Acinus

 Necrosis

 Steatosis

 Cholestasis

 Immune cell infiltrate

 Neoplasia

 Fibrosis or cirrhosis

Substance Hepatotoxic Effect

Necrosis Steatosis Cirrhosis Cancer

Acetaminophen +

Beryllium +

Carbon

tetrachloride

+ + + +

Chloroform + + +

Ethanol + +

Phosphorus + +

Tetrachloroethane + +

Urethane +

Vinyl chloride + Urine

Exhaled breath

Feces

Sweat

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Nephron: functional unit of the kidney

¼ of cardiac

output

Urine

Small, water-soluble molecules

Volatile compounds

 Benzene

 Carbon monoxide

 Carbon dioxide

Classes of toxins

 Dose-response relationship, threshold dose

and LD50 may be used as indicators of

relative toxicity of a substance.

 Toxic effects may vary in severity: simple

irritation to permanent injury to death.

 Toxic effects may be acute, subacute or

chronic.

 Toxins may enter the body through

inhalation, absorption, ingestion and

injection.

 In the human body, toxins are absorbed,

distributed, metabolized and excreted.