Assessment of Mumbai Waters for Heavy Metal Toxicity Using Zebrafish as Model Organisms
INTRODUCTION
The ever increasing population in the world today has led to the mounting of sewage, refuse and industrial waste everywhere. This waste has no place where it could be discarded and now it has found its way into the water bodies polluting the water and thereby creating a threat to the marine flora and fauna. In the environment, organisms are usually exposed not just to a single pollutant but rather to a mixture of these chemicals.
Mumbai is one of the busiest metropolitans in the country today housing over a million people alone and the garbage generated daily needs to be dumped somewhere. Mumbai, the capital of economic development, has been under deep stress due to industrial, commercial and population growth. Infrastructural facilities are not adequate to cater to the needs of the people. The environmental status of the coastal region around Mumbai has deteriorated due to wastewater discharges (Dhage et. al 2005). Toxic discharges by illegal means now find its way into the creeks and lakes which are often flushed out into the sea. The escalating accumulation of heavy metals is a hazard to life underwater and is amplifying the mortality rate of the fishes and other aquatic fauna. This buildup of waste in the waters not only affects the aquatic life but also mankind both directly and indirectly.
Fish is considered as one of the main protein sources of food for humans. Water pollution leads to affecting fish with toxic metals resulting from different sources like accidental spillage of chemical wastes, periodic precipitation contaminated with air borne pollutants, discharge of industrial or sewerage effluents, agricultural drainage and domestic wastewater. Toxicity with heavy metals to humans as a result of fish contamination has led to many studies on heavy metals in fish (Rashed 2000).
Contamination of aquatic ecosystems with heavy metals has been receiving increased worldwide attention due to their harmful effects on human health and other
The ever increasing population in the world today has led to the mounting of sewage, refuse and industrial waste everywhere. This waste has no place where it could be discarded and now it has found its way into the water bodies polluting the water and thereby creating a threat to the marine flora and fauna. In the environment, organisms are usually exposed not just to a single pollutant but rather to a mixture of these chemicals.
Mumbai is one of the busiest metropolitans in the country today housing over a million people alone and the garbage generated daily needs to be dumped somewhere. Mumbai, the capital of economic development, has been under deep stress due to industrial, commercial and population growth. Infrastructural facilities are not adequate to cater to the needs of the people. The environmental status of the coastal region around Mumbai has deteriorated due to wastewater discharges (Dhage et. al 2005). Toxic discharges by illegal means now find its way into the creeks and lakes which are often flushed out into the sea. The escalating accumulation of heavy metals is a hazard to life underwater and is amplifying the mortality rate of the fishes and other aquatic fauna. This buildup of waste in the waters not only affects the aquatic life but also mankind both directly and indirectly.
Fish is considered as one of the main protein sources of food for humans. Water pollution leads to affecting fish with toxic metals resulting from different sources like accidental spillage of chemical wastes, periodic precipitation contaminated with air borne pollutants, discharge of industrial or sewerage effluents, agricultural drainage and domestic wastewater. Toxicity with heavy metals to humans as a result of fish contamination has led to many studies on heavy metals in fish (Rashed 2000).
Contamination of aquatic ecosystems with heavy metals has been receiving increased worldwide attention due to their harmful effects on human health and other
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