By Dr. George Jacob
Kochi: As we observe the ‘World Environment Day’ on June 5, we forget that the rabid and rapid ‘development’ we are striving for our comfort comes at a huge price – that of denting the environment, the health of which and its sustenance is entirely our responsibility.
‘Development’ through industrialization in particular has made positive contributions to health, personal and social wealth. Health, educational services, transportation and communication have all been positively influenced. On a global scale, people are living longer and healthier.
However, sadly, industrialization and development has come to us at a price, brought about either (1) directly by exposure to harmful agents, or (2) indirectly through local and global environmental degradation.
Human beings have had to pay a heavy price globally with their lives, evidenced by the following examples:
• London (1952) by severe air pollution with sulphur dioxide and suspended particulate matter, resulting in heart and lung manifestations
• Toyama, Japan (1950s) by cadmium in rice resulting in diseases of bone and kidney
• Southeast Turkey (1955-61) by Hexachlorobenzine in seed grains, causing neurological disease and Porphyria, Minimata,
• Japan(1956) by methyl mercury in fish, causing neurological disease(Minamata Disease)
• various cities in the USA(1960s-70s) by lead in paint, causing anemia, behavioral and mental effects, Fukuoka
• Japan(1968) by polychlorinated biphenyls, causing skin disease and general weakness
• Iraq(1972) by Methyl mercury in seed grains, causing neurological disease, Chernobyl
• USSR(1986) by Iodine-134,Caesium-134 and 137 from a reactor explosion, causing radiation illness including cancer, thyroid diseases and birth defects
• Bhopal, India(1985) by Methyl Isocyanate, causing acute lung disease, Peru(1991) where many perished from Cholera outbreak
Environment is ransacked, concomitantly, along with and as the result of ‘development’. Large-scale agriculture, active use of toxic pesticides posing immense health hazards to workers and their households, pollution by fertilizers, biological waste from food industry and paper industry causing deleterious effects on waterways, reducing fishing and food supplies, are some examples.
Others being building of dams and roads (a new dam may create breeding grounds for Schistosomiasis, a debilitating disease affecting rice farmers working in water. A new road, ironically, reducing distances, contribute to faster spread of diseases like malaria from their endemic areas to areas farther away. ‘Development’, therefore comes at a price!
What effects can environment have on health?
Environment in which we live has three fundamental sets of components:
• Physical
• Chemical
• Biological
Physical hazards include those related to health effects of electromagnetic radiation and ionizing radiation and noise.
(a) Very strong electromagnetic radiation can cause:
• Electrical hazards: very strong radiation can induce current capable of delivering electric shock to man or animal. It can also overload and destroy electrical equipment. Stronger radiation can damage or cause explosion of power distribution transmitters, blackouts, and interfere with electromagnetic signals (eg; to radio, TV and telephone)
• Fire Hazards: extremely high power electromagnetic radiation can cause electric currents strong enough to create spark, which in turn ignite flammable material or gases, possibly leading to an explosion endangering lives.
• Biological hazards: the best understood biological effect of electromagnetic fields is to cause dielectric heating. Touching or standing near an antenna while a high-power transmitter is in operation can cause severe burns. These are exactly the kind of burns that could be caused inside a microwave oven. Fluorescent light bulbs and tubes internally produce Ultraviolet (UV) light, which is converted to visible light by the phosphor film inside a protective coating. When the film is cracked by mishandling or faulty manufacturing, the UV rays may escape at levels that could cause sunburn, or even skin cancer.LED lights emitting at wavelengths of 400-500 nanometers suppresses production of melatonin produced by the pineal gland, affecting disruption of man’s biological rhythm resulting in poor sleeping and rest periods
(b) Ionizing radiation, the second dangerous component that causes physical hazards after electromagnetic radiation is dangerous to human lives as it causes cancer. Though paradoxically, it is used in treating cancers! Most adverse health effects of radiation exposure may be grouped into two major categories:
• Deterministic effects(harmful tissue reactions) due in large part to the killing/malfunction of cells following high doses; and
• Stochastic effects, where the risk of cancer increases with dose of radiation, but the severity of effects is dose-independent.
It’s most common impact is the stochastic induction of cancer with a latent period of years, or decades after exposure. Other stochastic effects of radiation are cognitive decline and heart disease.
(c) Noise to the extent of being a pollutant causes:
Deafness, hypertension, stress, sleep impairment, aggression and antisocial behavior, besides others.
Chemical hazards: tobacco smoke constitutes the single biggest known airborne chemical risk to health, causing a spectrum of deleterious effects on the human body like numerous cancers, lung diseases like cancer, chronic bronchitis, emphysema, heart diseases like heart attack, diseases of blood vessels causing stroke and gangrene of limbs.
Other sources of airborne pollution are combustion of coal and other solid fuels (containing polycyclic aromatic hydrocarbons, sulphur dioxide, besides other agents like liquid petroleum products which generate carbon monoxide, oxides of nitrogen and other agents.
Industry and incineration can generate a wide range of products of combustion such as oxides of sulphur, nitrogen, polycyclic aromatic hydrocarbons, dioxins, etc. combustion of fossil fuel generates varying amounts of particulate matter.
It also adds to the environmental burden of carbon dioxide-an important ‘greenhouse’ gas, damaging the ozone layer.
Combustion of fuel generates hazardous substances in other ways, besides by chemical oxidation, such as by liberating benzene (from the cracking of petrol) or lead (from leaded petrol) other chemical pollutants, often overlooked, and considered insignificant are: nitrogen dioxide generated by gas cookers, modern building materials liberating gases or vapors such as formaldehyde, asbestos microfibers, generated from asbestos.
Biological hazards: These fall into two broad categories: infective and noninfective (allergic)
Waterborne diseases constitute large chunk of infective hazard. These include diseases viz; cholera, Hepatitis-A, typhoid. Allergic rhinitis, exacerbation of asthma and chronic bronchitis, caused by grass pollen grains, or fecal material from house dust mites constitute some of the allergic manifestations.
Putting one and one together, the above said calls for concerted efforts by the government and the citizens to protect environment by:
• Banning public smoking, clamping heavy fine on those smoking publicly,
• Improving quality of petroleum-based fuel,
• Stringent smoke-detection in vehicles, and fining those exceeding limits, banning senescent vehicles,
• Ensuring proper waste disposal
• Regulating use of fertilizers and insecticides in agriculture
• Ensuring availability of clean drinking water
• Ensuring quality of electric appliances, building materials and household items like electric bulbs,
• Ensuring safety of installations like nuclear and thermal plants.