SCIENCE
ENVIRONMENTAL SCIENCES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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The pollutants eventually concentrate in the ocean
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It is the volume of the pollutants, more than the time factor, that harms estuaries.
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The pollutants break down into still more dangerous toxins
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None of the above
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Detailed explanation-1: -Pesticides, automobile fluids like antifreeze, oil or grease, and metals such as mercury or lead have all been found to pollute estuaries. These substances can enter an estuary through industrial discharges, yard runoff, streets, agricultural lands, and storm drains.
Detailed explanation-2: -Estuaries and their surrounding wetlands filter out pollutants such herbicides, pesticides, heavy metals and excess nutrients and sediments. For this reason, estuaries comprise one of the most fertile ecosystems, but also have the potential be the most polluted.
Detailed explanation-3: -The health of our estuaries is threatened by coastal development, declining water quality and loss of habitat for native species. Estuaries are impacted by pressures from human activities as well as natural events such as storms and floods.
Detailed explanation-4: -The main water pollutants include bacteria, viruses, parasites, fertilisers, pesticides, pharmaceutical products, nitrates, phosphates, plastics, faecal waste and even radioactive substances. These substances do not always change the colour of the water, meaning that they are often invisible pollutants.