The harmful effects of toxic chemicals in the environment
The toxic chemicals are the substance that can be poisonous or cause the health effects , They don’t break down easily in the environment , they can build up the tissues of small organisms , they can move up through the food chain .
The chemicals can be toxic because they can harm us when they enter or contact the body , they can threaten the human health , The motor vehicle emissions of nitrogen and sulphur oxides cause the acid rain which poisons the fish and other aquatic organisms in the rivers and lakes .
carbon dioxide gas causes the greenhouse effect and the climate change , Chlorofluorocarbons ( CFCs ) cause the destruction of ozone in the stratosphere and they create the possibility of serious environmental damage from ultraviolet radiation .
The oil drilling and transport , mining and maritime operations all result in the accidental introduction of toxic materials into the marine environment , and the leakage from the storage tanks and the pipelines , and the seepage from the waste dumps .
The toxic materials or substances can poison people and other life, They can cause illness and even death if swallowed or absorbed through the skin , where the pesticides , the weed killers , and many household cleaners are toxic , they occurs as a result of a variety of human activities .
The industries and the sewage treatment plants discharge the wastes which contain the toxic substances directly into the waterways , These direct pipeline discharges are called the point sources .
The fuel combustion from means of transports , and the power plants contain numerous chemicals that drift in the atmosphere and rain down upon or absorb into the surface of the ocean and other bodies of water .
The sources of the radioactive contamination are the plutonium processing plants , the nuclear power plants , the nuclear submarines and the nuclear waste dumps , When they are incinerated and discharged , they can cause the marine pollution .
The disinfecting products are flushed into the sewage systems and out through the treatment plant discharge , and they are washed from the houses and the septic tanks into the groundwater and the streams .
Effects of some toxic chemicals
Arsenic is a potent poison , Many water supplies close to mines are contaminated by it , Arsenic causes harm by disrupting metabolism at the cellular level, and Arsenic can cause fetal death and malformations in many mammal species .
Cadmium can be toxic to the freshwater organisms , The shellfish can concentrate cadmium in levels that are harmful to people who eat them , zinc can kill young salmon as they swim out of their nest gravel , It can kill many adult fish species .
Many petrochemicals can poison the fish , and kill their eggs and larva , they are toxic to the algae and the invertebrates , And they can cause changes in the metabolism , reduced feeding , and poor shell formation , They can reduce the reproductive success of invertebrates .
The petrochemicals can damage the skin , the lungs , the liver , and the kidneys of birds and mammals as well as they increase vulnerability to deadly infections by suppressing the immune system , they can damage the plants , and they stop seed germination .
The pesticide DDT builds up in the food chain and can last for decades in the environment , DDT is linked to the decline of the bald eagle , the peregrine falcon , and other birds because it makes their egg shells too thin , and decreasing the survival of the chicks .
Lead can impair the brain development and learning in the children and can affect the behavior , high blood pressure , the reproduction , and the growth in both the children and the adults .
Mercury is very toxic , It is mostly known as a neurotoxin which means that it harms the brain and nervous system , and it is linked to the kidney and the liver damage and possibly the cancer .