Industrial waste: It is represented by different toxic substances some of which are lead, sulphur, asbestos, mercury, nitrates and other noxious pollutants. The factories are the ones to be blamed for the enormous amounts of industrial waste in every country these days. This is so due to the fact that most of them do not have appropriate waste management systems established and this leads to the unimpeded flow of these chemicals. Once in it, they can cause a lot of problems such as change in the color and temperature, they can also dissolve or deposit there and thus seriously affect the quality of the aquatic life and also threaten the survival of many species.
Sewage: The sewage and water pollution which almost every household produces is already full of chemicals prior being released into the sea. The sewage contains pathogens- various types of bacteria and chemicals which adversely affect our health. The microorganisms in the sewers either cause deadly diseases or serve as breeding areas for other creatures which carry them. The malaria is only one example of a disease inflicted by such disease carriers.
Mining activities: During the performance of mining activities the extracted coal or other minerals are mixed up. This can lead to a rise in the quantity of toxic substances which in turn can lead to health problems. The sulfides and the metal waste from the raw materials are detrimental for the water and the creatures living in it.
Marine dumping: It takes from several weeks to 200 years for the household rubbish such as aluminum, paper, plastic or glass to be decomposed. However, there are countries which have chosen to deposit this sort of garbage into the sea. It is not difficult to imagine that this would turn out to be problematic and cause damage to the entire marine life.
Accidental Oil leakage: Oil spills cannot be predicted as they are accidental but since oil does not dissolve it literally kills countless animals. The oil spill recovery may take years.
Burning of fossil fuels: Coal and oil are fossil fuels which release considerable amounts of ash into the atmosphere when burnt. The acid rains, for example are the product of these toxic particles which have mixed up with water vapour. The fossil fuels immensely contribute to the global warming because a lot of carbon dioxide is produced after fossil fuels burning.
Chemical fertilizers and pesticides: Farmers use chemical fertilizers and pesticides so as to protect their crops from the bad weather conditions, pests such as insects or bacteria and promote the growth of the plants. Nevertheless, when in contact with water, these substances have a negative impact on both plants and animals. What is more, when it rains the pesticides and the fertilizers mix up with rain and thus go into canals and rivers where they endanger the aquatic life.
Leakage from sewer lines: A leakage from the sewer lines can make the water we consider potable unfit for drinking. Furthermore, if not fixed on time, the leakage can become a breeding ground for different disease- carrying insects.
Global warming: The greenhouse effect increases not only the temperature of the air but also of the water which in turn can cause the death of many marine species and their carcasses will further have negative effects on the survived ones.
Radioactive waste: The highly toxic chemical Uranium is used in the nuclear energy production plants. In order the nuclear waste not to cause an accident it has to be appropriately disposed off. As mankind has already seen a mistake in this process can cause nuclear disasters as the ones in Russia and Japan can take place and claim many lives not only at the moment of the accident but also in the years to come.
Urban development: Billions of people live on the planet. They all need food, shelter and clothes. In order the demand for food to be satisfied, more fertilizers are used. In order buildings to be constructed, trees are cut down leading to deforestation which has also become a huge problem. We consume more and respectively throw out more garbage which means that the landfills are more and the presence of chemicals from the industries is too more than ever before.
Leakage from the landfills: Most of the landfills are in the open air. Not only do they make the area look ugly but they produce an awful smell. What is worse is that when it rains they leak and contaminate the water below.
Animal waste: When there is rain, the animal waste goes into the rivers, mixes up with the already present chemicals and causes numerous of diseases which are borne by the water pollution. Diarrhea, typhoid and cholera are just a few of them.
Underground storage leakage: Some petroleum and coal products are transported through pipelines situated underground. In case of an accident and a subsequent leakage, serious problems such as soil erosion can occur.