All About Water Pollution

Tuesday, 19 June 2007

Causes of Water Pollution [Part 2]

Personal Care Products, Household Cleaning Products, and Pharmaceuticals

Whenever we use personal-care products and household cleaning products—whether they be laundry detergent, bleach, or fabric softener; window cleaner, dusting spray, or stain remover; hair dye, shampoo, conditioner, or Rogaine; cologne or perfume; toothpaste or mouthwash; antibacterial soap or hand lotion—we should realize that almost all of it goes down the drain when we do laundry, wash our hands, brush our teeth, bathe, or do any of the other myriad things that incidentally use household water. Similarly, when we take medications, we eventually excrete the drugs in altered or unaltered form, sending the compounds into the waterways. Studies have shown that up to 90% of your original prescription passes out of you unaltered. Animal farming operations that use growth hormones and antibiotics also send large quantities of these chemicals into our waters.

Unfortunately, most wastewater treatment facilities are not equipped to filter out personal care products, household products, and pharmaceuticals, and a large portion of the chemicals passes right into the local waterway that accepts the treatment plant's supposedly clean effluent.

Study of the effects of these chemicals getting into the water is just beginning, but examples of problems are now popping up regularly:

Scientists are finding fragrance molecules inside fish tissues.
Ingredients from birth control pills are thought to be causing gender-bending hormonal effects in frogs and fish.
The chemical nonylphenol, a remnant of detergent, is known to disrupt fish reproduction and growth

Sewage

In developing countries, an estimated 90% of wastewater is discharged directly into rivers and streams without treatment. Even in modern countries, untreated sewage, poorly treated sewage, or overflow from under-capacity sewage treatment facilities can send disease-bearing water into rivers and oceans. In the US, 850 billion gallons of raw sewage are sent into US rivers, lakes, and bays every year by leaking sewer systems and inadequate combined sewer/storm systems that overflow during heavy rains. Leaking septic tanks and other sources of sewage can cause groundwater and stream contamination.

Beaches also suffer the effects of water pollution from sewage. The chart below shows the typical reasons that about 25% of the beaches in the US are put under water pollution advisories or are closed each year. It's clear that sewage is part of the problem, even in what is supposedly the most advanced country in the world.

Air Pollution

Hey, I thought we were doing WATER pollution causes! Well, surprisingly enough, air pollution contributes substantially to water pollution. Pollutants like mercury, sulfur dioxide, nitric oxides, and ammonia deposit out of the air and then cause problems like mercury contamination in fish, acidification of lakes, and eutrophication (nutrient pollution). Most of the air pollution that affects water comes from coal-fired power plants and the tailpipes of our vehicles, though some also comes from industrial emissions.

Carbon Dioxide

According to the United Nations Environment Programme, a 15-year-long study of the role of man-made CO2 in the earth's oceans found that the oceans had absorbed enough CO2 to already have caused a slight increase in ocean acidification. The fear is that further CO2 uptake will increase acidification even more and cause the carbonate structures of corals, algae, and marine plankton to dissolve. This could have significant impacts on the biological systems of our oceans.

Heat

Heat is a water pollutant—increased water temperatures result in the deaths of many aquatic organisms. These increases in temperature are most often caused by discharges of cooling water by factories and power plants.

Global warming is also imparting additional heat to the oceans. The impact on marine life is unknown at this point, but it's likely to be significant.

Noise

Many marine organisms, including marine mammals, sea turtles and fish, use sound to communicate, navigate, and hunt. The ever-increasing din of noise from ship engines and sonars has a negative effect. Because of this noise pollution, some species may have a harder time hunting; others may have a harder time detecting predators; still others may just not be able to navigate properly.

In a well publicized case in 2000, at least 17 whales were stranded on beaches in the northern Bahama Islands, with the likely cause being US Navy vessels operating mid-frequency sonar systems nearby.

2:41 pm

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