CONTENTS 
Page 
Continued, But Modified, Use of Animals in Testing 175 
Avoiding Duplicative Testing 176 
Reducing Pain and Distress 176 
Use of Living Systems in Testing 177 
In Vitro Systems 177 
Nonanimal Organisms ..179 
Use of Nonliving Systems in Testing 180 
Chemical Systems 180 
Mathematical and Computer Models . 180 
Epidemiologic Data on Humans 181 
The LD 50 Test 181 
Using Fewer Animals 182 
The Limit Test and Other Refinements 182 
In Vitro and Nonanimal Methods 182 
Skin and Eye Irritation 183 
In Vitro Tests 183 
Chick Embryo 183 
Repeated -Dose Toxicity Tests 184 
Hepatotoxicity 185 
Neurotoxicity 185 
Mutagenicity 185 
Micro-organism Tests 186 
In Vitro Tests 186 
Tests Using Insects . 186 
Carcinogenicity 187 
The Ames Test 187 
Use of the Ames Test in a Battery of Tests 188 
Current Trends 188 
Summary and Conclusions 190 
Chapter 8 References 191 
Table 
Table No. Page 
8-1. The Response of Known Human Carcinogens to Rodent Carcinogenicity 
and Bacterial Mutagenicity Assays 188 
Figure 
Figure No. Page 
8-1. Chronological Sequence of Chick Embryo Chorioallantoic 
Membrane Assay 184 
