11.4.5 Exposure
180
11.4.6 Metabolism
181
11.5 References
182
11.6 Review Questions
184
CHAPTER 12 SOIL AND WATER POLLUTION –
ENVIRONMENTAL METALS AND
METALLOIDS
185
12.1 Introduction
185
12.2 Lead
186
12.2.1 Characteristics and Use of Lead
186
12.2.2 Sources of Lead Exposure
186
12.2.2.1 Airborne Lead
186
12.2.2.2 Waterborne Lead
187
12.2.2.3 Lead in Food
188
12.2.2.4 Lead in Soils
188
12.2.3 Lead Toxicity
188
12.2.3.1 Lead Toxicity to Plants
188
12.2.3.2 Lead Poisoning in Animals and Fish
189
12.2.3.3 Health Effects of Lead in Humans
189
12.2.4 Biological Effects of Lead
191
12.2.5 Lead and Nutrition
192
12.3 Cadmium
194
12.3.1 Introduction
194
12.3.2 Characteristics and Use of Cadmium
194
12.3.3 Exposure to Cadmium
195
12.3.3.1 Airborne Cadmium
195
12.3.3.2 Waterborne Cadmium
195
12.3.3.3 Cadmium Pollution of Soils
196
12.3.3.4 Cadmium in Food
196
12.3.4 Metabolism of Cadmium
196
12.3.5 Cadmium Toxicity
197
12.3.5.1 Toxic Effects on Plants
197
12.3.5.2 Effects of Cadmium on Animals
198
12.3.5.3 Effects of Cadmium on Humans
199
12.3.6 Biological Effects of Cadmium
201
12.3.7 Cadmium and Nutrition
202
12.4 Mercury
203
12.4.1 Introduction
203
12.4.2 Extraction and Uses of Mercury
203
12.4.3 Sources of Mercury Pollution
204
12.4.4 Biotransformation of Mercury
204
12.4.4.1 Biomethylation of Mercury
205
12.4.4.2 Demethylation of Methylmercury
205
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Ref: 4365 MING-HO YU Prelims Page: xix 4-24