The 10 Worst Forms of Pollution For everything we take from the Earth, there
is a byproduct or consequence. Perhaps pollution is a symptom of nature's imbalance. Some people
reap from the Earth, but countless others become sick, displaced or harmed due to the
resulting pollution — affecting wildlife and more. On the off chance that a guilty
conscience is an unknown symptom of overexploitation, here's a list of the 10 worst forms of pollution
and their effects on humans. 1. Oil spills
In the wake of the Gulf oil spill, the harmful effects of marine oil spills are obvious.
Birds, fish and other marine life can be devastated from a spill, and the ecosystems often take
decades to recover. The oil is ingested by some animals, allowing pollutants to enter
the food chain, harming fisheries and other industries in the region. Many people don't
realize that most oil pollution actually comes from land-based activity. One way or another,
oil has seeped into nearly all of Earth's ecosystems.
2. Radioactive waste Most radioactive waste comes as a result of
nuclear power plants and nuclear weapons reprocessing, but it can also be the byproduct of medical
and industrial procedures, coal or mineral mining, or oil processes. All radioactive
waste carries the potential for water and air contamination. Radiation poisoning can
cause severe genetic damage and may result in cancer. Some forms of radioactive waste
can take thousands of years to decay, so once contamination occurs, the problem is often
there to stay. 3. Urban air pollution
According to the World Health Organization, 2.4 million people die every year primarily
because of air pollution. Urban areas such as Los Angeles, Mumbai, Cairo, Bejing and
many of the world's most populated cities have the worst air quality. Air pollution
has been strongly correlated with increased rates of asthma, and pollution from automobiles
has a strong link to pneumonia-related deaths. One of the worst cases of urban air pollution
happened in London in 1952, when about 8,000 people died over the course of a few months
because of a single smog event. 4. Mercury poisoning
Most man-made mercury pollution is emitted by coal power plants, but mercury can also
be a byproduct of gold mining, cement production, iron and steel production and waste disposal.
Once in the environment, mercury can accumulate in the soil, water and atmosphere. It is particularly
apparent in the marine food chain. The consumption of fish is by far the most significant source
of mercury contamination in humans. Some effects of mercury poisoning include impaired cognitive
function, kidney failure, loss of hair, teeth or nails, and extreme muscle weakness.
5. Greenhouse gases The most common greenhouse gases are water
vapor, carbon dioxide, methane, nitrous oxide and ozone. Carbon dioxide from the burning
of fossil fuels has greatly increased since the Industrial Revolution. As greenhouse gases
accumulate in the atmosphere, they cause overall warming and climate change. A few of the profound
effects of rapid climate change include rising sea levels, loss of biodiversity and the melting
of snowpack, which could threaten the world's fresh water supply.
6. Pharmaceutical pollution Pharmaceutical waste is becoming one of the
world's biggest pollution concerns. Millions of doses of drugs are prescribed to people
annually, and even more antibiotics are given to livestock. Those chemicals eventually make
their way into the water supply. There is a natural risk to human health, but the bigger
fear is that the pollution will ease the evolution of superbugs — bacteria that are immune
to antibiotics. 7. Plastics
Many plastics are toxic. Vinyl chloride (PVC), is a known carcinogen, and bisphenol A (BPA)
can disrupt endocrine function, can cause insulin resistance and it has been linked
to heart disease. Plastics biodegrade slowly, in some cases lasting for hundreds of thousands
of years. Waste accumulated from excessive use of plastics has become a worldwide problem.
Gigantic islands of plastic trash have been known to accumulate in the North Pacific Gyre,
the most famous of which is the Great Pacific Ocean Garbage Patch.
8. Untreated sewage Lackluster sewage treatment in some parts
of the world is a major source of disease and water contamination. In Latin America
only 15 percent of wastewater is treated, and sewage treatment is virtually unheard
of in sub-Saharan Africa. In addition to the sanitation hazard, untreated sewage also allows
for redistribution and accumulation of other pollutants in the water table.
9. Lead poisoning Lead is toxic and is harmful to most of the
body's organs, including the heart, kidneys, nervous system, reproductive system, bones
and intestines. It is especially dangerous to children because their bodies are still
developing. Lead was a common component of paint until 1977, and is still used in certain
kinds of paints. It can leak into the water and food supplies. Another major cause of
contamination is occupational exposure in industrial settings and plants that process
lead-acid batteries. 10. Agricultural pollution
Pesticides, chemicals and untreated manure are the most dangerous forms of agricultural
pollution because they end up in the water supply. Excessive agricultural runoff can
prompt the growth of large algal blooms, which starve waterways of oxygen and create "dead
zones." Excessive erosion can also be a problem, and even accidental milk spillage from dairies
can be a serious contaminant. According to the Environmental Protection Agency, half
of all surface water pollution in the U.S. is attributable to agricultural sources.