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Toxic waste is generally described as many discarded material that is dangerous to any life form, including humans, animals and plant life. Toxic waste can pollute the air, land and water. Toxic waste is defined as liquid, solid, contained gas or sludge waste that contains properties that are dangerous or potentially harmful to human health or the environment.
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Wastes are regulated by the Environmental Protection Agency(EPA) under the Resource Conservation and Recovery Act, according to the EPA handbook on toxic waste. Despite containing toxic and dangerous elements, most waste does not end up being monitored and controlled under the RCRA.
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Although the EPA has a detailed listing of what is considered a waste, hazardous waste generally has one or more of these four characteristics: flammability corrosiveness reactivity toxicity.
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Toxic waste has a negative effects on environmental and public health. For humans: contact with toxic chemical waste from laboratories may result in skin burns and disfigurement. Exposure to carbon monoxide may cause headache and trouble thinking. Toxic wastes such as lead, mercury or cadmium may cause liver or kidney damage, central nervous system damage, cancer and birth defects.
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For environment: animals may ingest lead while searching for food, resulting in damage to their central nervous system. Fish accumulate toxins in their bodies from contaminated water. As a result these contaminants enter the food chain. Lead absorption in plants may lead to stunted growth, chlorosis and blackening of root system. This inhibits photosynthesis, affects membrane structure and permeability in plants.
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People encounter these toxins buried in the ground, in stream runoff, in groundwater that supplies drinking water, or in floodwaters. Some toxins, such as mercury, persist in the environment and accumulate.
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Toxic wastes containing organic carcinogens can be destroyed by incineration at high temperatures, which is expensive. However, if the waste contains heavy metals or radioactive isotopes, these must be separated and stored, as they cannot be destroyed.
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Tonnes of toxic waste collected from British municipal dumps is being sent illegally to Africa in flagrant breach of this countrys obligation to ensure its rapidly growing mountain of defunct televisions, computers and gadgets are disposed of safely.
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Hundreds of thousands of discarded items, which under British law must be dismantled or recycled by specialist contractors, are being packaged into cargo containers and shipped to countries such as Nigeria and Ghana, where they are stripped of their raw metals by young men and children working on poisoned waste dumps.
