The health effects of industrial pollution
Industrial activities are a major source of air, water and land pollution, leading to illness and loss of life all over the world. The World Health Organization estimates that outdoor air pollution alone accounts for around 2% of all heart and lung diseases, about 5% of all lung cancers, and about 1% of all chest infections.
One of the worst industrial disasters of all time took place in Bhopal , India , in December 1984. In the three days after the first gas leak occurred, around 8,000 people died. Many thousands more still feel the effects two decades on.
While Bhopal was a single event that caused the death of thousands of people in a very short period of time, pollution is often a slow, continuous process. An example is air pollution caused by industrial activity, motor vehicle exhaust and the burning of household stoves. Research on the relationship between levels of daily outdoor air pollution and the prevalence of diseases, based on hospital admission reports, shows that for every 10 microgram increment in the concentration of respirable particulate matter in the air, the risk of death from respiratory illness increases by 1%. Inside homes, air pollution caused by burning fossil fuel (such as coal or wood), used in many Indian households, is linked to tuberculosis and respiratory illnesses among women and children. Worldwide, indoor air pollution accounts for about 34% of all respiratory illnesses.
Pollution and pollutants
A simple definition of pollution could be the presence of high quantities of any entity in the wrong place. This indicates that a specific substance cannot in itself be labeled a pollutant. It becomes a pollutant when concentrations of the substance are too great to sustain health in any given place. For example, high concentrations of respirable particulate matter in lung tissue harm the respiratory system. Another example is inorganic arsenic. When concentrations of inorganic arsenic exceed 10 micrograms/L in the groundwater, significant adverse health effects occur in people who consume that water.
Pollutants are present everywhere in our environment and enter our body through the air we breathe (respiratory system), the food we eat and water we drink (gastrointestinal system), or through skin contact.
Health effects
Pollutants affect our health in several ways. These include direct irritation of target organs or metabolic changes within cells.. Sometimes, the effects may take years to develop. Asbestos fibres, for example, are small needle-shaped silicate crystals that penetrate deep into lung tissue and evoke reactions. It takes around 20 years for some illnesses to manifest.
Other health effects involve metabolic pathways in our bodies -- pathways of chemical reactions in our cells -- where they may interfere with energy production or cellular repair mechanisms. For example, exposure to inorganic arsenic is common among people who work in copper smelters or live around them. Exposure to inorganic arsenic also occurs among people who consume water from shallow tube wells in areas where the groundwater contains high levels of inorganic arsenic.
When it enters the body, inorganic arsenic is transformed through the same chemical reactions that are necessary to maintain the repair processes of DNA molecules within the cells. As a result of excess exposure to arsenic, and demands on these reactions, faulty repair of DNA molecules causes tumours to form.