PRINCIPLES OF ENVIRONMENTAL TOXICOLOGY AND CONTAMINATION (PART I)

Table of Contents

1. Index
2. UNIT 1 - General principles
3. UNIT 2 - Main sources of environmental contamination
4. UNIT 3 - Air Pollution
5. Unit 4 - Water and soil Pollution
   1. Introduction
   2. Sources of Water and Soil Pollutants
   3. Examples of Water and Soil Pollutants and their Environmental and human health effects
   4. Other Environmental and human health effects of water pollution
   5. Other environmental and human health effects of soil pollution
6. Glossary of key terms associated with environmental toxicology

Other Environmental and human health effects of water pollution

As noted in section 3, water pollution extensively affects environmental (e.g. aquatic ecosystems) and human health. It is known that consumption of contaminated water as well as swimming in this water can cause skin diseases, reproductive problems, cancer, and stomach ailments in humans. Water pollution also causes approximately 14,000 deaths per day, mostly due to contamination of drinking water by untreated sewage in developing countries.

Other environmental effects of water pollution:

• Sewage containing flush chemicals and pharmaceuticals causes great problems once released into the water. Particulate matter of chemicals and other substances do not dissolve easily in water. These suspended particulate matters settle at the bottom of the water body harming the aquatic life (at the floor of the water bodies).
• Water pollution due to acid rain also harms the aquatic life, as referred in chapter 3.
• The increase in the content of biodegradable matter in the water encourages the growth of microorganisms which end up using most of the oxygen. This results in oxygen depletion, killing aerobic organisms, and in the production of toxins such as ammonia and sulphides.
• The increasing of water temperature (e.g. heated water discharge from the condensers of steam turbine electric power plants) also impacts the aquatic ecosystem. For example, the coral reefs are bleached due to warmer temperatures. Warmer waters forces indigenous water species to seek cooler water, causing an ecological shift of the affected area. Furthermore, heated water also encourages the growth of algae and, consequently, decreases the oxygen in the water, killing fish and other aquatic organisms.
• Water pollution causes soil erosion in streams, rivers and also flooding due to accumulation.