This work is licensed under a . Your use of this

advertisement

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike License . Your use of this material constitutes acceptance of that license and the conditions of use of materials on this site.

Copyright 2015, The Johns Hopkins University and Michael Trush. All rights reserved. Use of these materials permitted only in accordance with license rights granted. Materials provided “AS IS”; no representations or warranties provided. User assumes all responsibility for use, and all liability related thereto, and must independently review all materials for accuracy and efficacy. May contain materials owned by others. User is responsible for obtaining permissions for use from third parties as needed.

1

Toxicity Testing, Dose Response, and Risk Assessment

James D. Yager, PhD

Johns Hopkins University

Section A

Introduction to Risk Assessment

!

The material in this video is subject to the copyright of the owners of the material and is being provided for educational purposes under rules of fair use for registered students in this course only. No additional copies of the copyrighted work may be made or distributed.

Organization of this Lecture

!

Section A: introduction to risk assessment and elements of the risk assessment process

!

Section B: toxicity assessment (testing)

!

Section C: in vivo tests or bioassays

!

Section D: in vitro tests: genotoxicity

!

Section E: in vitro tests: cellular toxicity

!

Dose-response relationships

!

Application of testing and dose-response to risk assessment

4

“Hazardous to my Health”

“Another day—another chance something will be found hazardous to my health.”

5

The Toxicological Paradigm

6

National Geographic: October, 2006

Source: David Ewing Duncan. (October, 2006). “The Pollution Within.”

National Geographic.

7

U.S. Agencies for Toxic Chemical Regulation

Agency Legislation

FDA

EPA

OSHA

CPSC

DOT

Federal Food, Drug, and Cosmetic Act

Federal Insecticide, Fungicide, and

Rodenticide Act; Clean Air Act; Safe

Drinking Water Act and 1996 Amendment;

Food Qual. Protection Act 1996; Toxic

Substances Control Act; Superfund

Amendments and Reauthorization

Occupational Safety and Health Act;

Federal Hazardous Substance Act

Consumer Product Safety Act

Hazardous Materials Transportation Act

Covers

Drugs; food additives; food contact substance; coloring

(no carcinogens)

Air and water pollutants; contaminated sites; environmental estrogens/endocrine disruptors; pesticides; toxic substances

Occupational exposure

Consumer products

Shipping hazardous materials

Source: adapted by CTLT from: NRC/NAS, Toxicity Testing for Assessment of Environmental Agents, 2006

8

What Is Risk Assessment?

!

Risk assessment

is a characterization of the probability of potentially adverse health effects from human exposures to environmental hazards

9

Risk Assessment Process

10

Risk Assessment Process

11

Risk Assessment Process

!

Exposure assessment (what, who, how, extent)

-

What

exposure(s) were/are/anticipated to occur?

!

Chemicals/agents

-

Who

is exposed? Identify exposed populations

!

Age (adults, children, elderly), gender, lifestyle, genetic susceptibilities

-

How:

identify routes of exposure

-

Extent:

estimate degree of exposure

12

What, Who, How, Extent

13

Download