Electronic Waste: E – WASTE
- The discarded and end-of-life electronic products ranging from computers, equipment, home appliances, audio, and video products and all of their peripherals are popularly known as Electronic waste (E-waste).
- E-waste is not hazardous if it is stocked in safe storage or recycled by scientific methods or transported from one place to the other in parts or in totality in the formal sector. The e-waste can, however, be considered hazardous if recycled by primitive methods.
E-Waste in India
- India generates about 18.5 lakh metric tonnes (MT) of electronic waste every year, with Mumbai and Delhi-NCR accounting for the biggest chunk. The figure is likely to reach up to 30 lakh MT per year by 2018.
- Bangalore, Chennai, Kolkata, Ahmadabad, Hyderabad, Pune, Surat and Nagpur are other important cities generating a substantial amount of e-waste.
- Among the eight largest e-waste generating states, Maharashtra ranks first followed by Tamil Nadu (2nd), Andhra Pradesh (3rd), Uttar Pradesh (4th), Delhi (5th), Gujarat (6th), Karnataka (7th) and West Bengal (8th).
- Over half of the e-waste generated in the developed world are exported to developing countries, mainly to China, India, and Pakistan, where metals like copper, iron, silicon, nickel, and gold are recovered during the recycling process.
- Unlike developed countries, which have specifically built facilities for recycling of e-waste, recycling in developing countries often involves manual participation thus exposing workers to toxic substances present in e-waste.
Heavy Metal Toxicity and Methods Of Their Prevention
- Toxic metals are dispersed in the environment through metal smelting industrial emissions, burning of organic wastes, automobiles, and coal-based power generation.
- Heavy metals can be carried to places far away from their source of origin by winds when they are emitted in gaseous form or in form of fine particulates.
- Rain ultimately washes the air having metallic pollutants and brings them to the land and to water bodies.
- Heavy metals may endanger public health after being incorporated into the food chain.
- Heavy metals cannot be destroyed by biological degradation.
- Incidence of heavy metal accumulation in fish, oysters, mussels, sediments and other components of aquatic ecosystems have been reported from all over the world.
- The heavy metals often encountered in the environment including lead, mercury, arsenic, chromium. These are known to cause toxic effects in living organisms.
- Lead enters the atmosphere from automobile exhaust. Tetraethyl lead (TEL) was added to petrol as an antiknock agent for the smooth running of automobile engines.
- TEL has now been replaced by other anti-knock compounds to prevent the emission of lead by automobiles. Lead in petrol is being phased out by the introduction of lead-free petrol.
- Many industrial processes use a lead and it is often released as a pollutant. Battery scrap also contains lead. It can get mixed up with water and food and create cumulative poisoning.
- Lead can cause irreversible behavioral disturbances, neurological damage, and other developmental problems in young children and babies. It is a carcinogen of the lungs and kidneys.
- In Japan, mass mercury poisoning (Minamata disease) was observed in the 1960s, caused by eating fish from Minamata Bay which was contaminated with methyl mercury.
- The largest source of mercury pollution is through aquatic animals such as fish which accumulate mercury as methyl mercury.
- Mercury kills cells in the body and damages organs which come in contact with mercury and thus impairs their functioning.
- Inhalation of mercury vapors is more dangerous than its ingestion.
- Chronic exposure causes lesions in the mouth and skin and neurological problems.
- Typical symptoms of mercury poisoning are irritability, excitability, loss of memory, insomnia, tremor, and gingivitis.
- Exposure to mercury can be prevented by taking care that mercury is not released in the environment as well as by replacing mercury by other materials.
- Mercury thermometers used earlier are getting replaced by mercury free
- Arsenic is associated with copper, iron and silver ores.
- Arsenic is also emitted from fossil fuel burning.
- Liquid effluents from fertilizer plants also contain arsenic.
- Ground water contamination with arsenic is very common in areas where it is present.
- Chronic arsenic poisoning causes melanosis and keratosis (dark spots on the upper chest, back and arms are known as melanosis. The next stage is keratosis in which palms become hard) and leads to loss of appetite, weight, diarrhea, gastrointestinal disturbances, and skin cancer.
- Surface waters are generally free from arsenic pollution and should be preferred for drinking and cooking.
- Alternatively, the tube well/ hand pump water should be purified to remove arsenic before consumption. Techniques for removing arsenic from water are available.
- Mining, especially of zinc and metallurgical operations, electroplating industries, etc., release cadmium in the environment.
- It may enter the human body by inhalation or from aquatic sources including fish, etc.
- It may cause hypertension, liver cirrhosis, brittle bones, kidney damage, and lung cancer.
- Itai-Itai disease first reported from Japan in 1965 was attributed to cadmium contamination in water and rice caused by the discharge of effluents from a zinc smelter into a river.
Other Heavy Metals
- Metals such as zinc, chromium, antimony, and tin enter food from cheap cooking utensils.
- Preserved foods stored in tin cans also cause contamination by tin.
- Zinc is a skin irritant and affects the pulmonary system.
- Problems of heavy metal toxicity can be prevented by avoiding the use of utensils made from materials containing these heavy metals or use of drinking water and consuming fish having these heavy metals.
Occupational Health Hazards
Black lung disease
- In coal mining areas coal dust is the main air pollutant. The deposits of coal dust make miners lungs look black instead of a healthy pink and hence the name black lung disease.
- Black lung disease is the common name for pneumoconiosis (CWP) or anthracosis, a lung disease of older workers in the coal industry, caused by inhalation over many years, of small amounts of coal dust.
- The particles of fine coal dust accumulate in the lungs. Eventually, this build-up causes thickening and scarring making the lungs less efficient in supplying oxygen to the blood.
- In some cases, progressive massive fibrosis develops, in which damage continues in the upper parts of the lungs even after exposure to dust has ended.
- X-rays can detect black lung disease before it causes any symptoms.
- Workers in mining, manufacturing, and construction industries are exposed to high levels of noise which is a very important stress factor.
- Sound levels higher than 80 to 90 dB for more than eight hours is harmful to the human ear. Some of the adverse effects of sound are –
- Noise leads to emotional disturbances such as annoyance, disturbed sleep, lack of concentration and reduced efficiency.
- Auditory fatigue – Occurs when the noise level is in the range of 85 to 90 dB e.g. noise of a food blender.
- Deafness or impaired hearing – It may be temporary or permanent. Temporary hearing loss occurs on continuous exposure to noise as in the case of telephone operators.
- Repeated or continuous exposure to noise more than 90 dB may result in permanent loss of hearing.
- Interference with speech and communication.
- Annoyance: Most people are annoyed by the noise and some may become neurotic. Neurotic people lose their temper quickly and become irritable.
- Efficiency: High level of noise at the workplace reduces working efficiency. The quiet environment helps in increasing efficiency.
- The general change in the body: Exposure to noise increases blood pressure, pulse rate, breathing and sweating or headache.
Chemicals and Biological Agents
- Workers in many industries are exposed to chemicals which are hazardous and maybe even carcinogenic such as in textiles, cement and construction industries.
- Substances such as benzene, chromium, nitrosamines, and asbestos may cause cancers of lung, bladder, skin, mesothelium, liver, etc.
- Occupational asthma is caused due to exposure to organic dust, microorganisms, bacteria, fungi and molds, and several chemicals.
- Silicosis first reported from Kolar gold mines in 1947 is a common disease among miners, pottery and ceramic industry workers.
- Pneumoconiosis and byssinosis are common among mica and textile industry workers respectively.
Treatment and disposal of solid waste
- Open dumps refer to uncovered areas that are used to dump solid waste of all kinds.
- The waste is untreated, uncovered, and not segregated. It is the breeding ground for flies, rats, and other insects that spread disease.
- The rainwater runoff from these dumps contaminates nearby land and water thereby spreading disease. Treatment by open dumps is to be phased out.
- It is a pit that is dug in the ground. The garbage is dumped and the pit is covered with soil every day thus preventing the breeding of flies and rats.
- After the landfill is full, the area is covered with a thick layer of mud and the site can thereafter be developed as a parking lot or a park.
- Problems – All types of waste are dumped in landfills and when water seeps through them it gets contaminated and in turn pollutes the surrounding area. This contamination of groundwater and soil through landfills is known as leaching.
- Sanitary landfill is more hygienic and built in a methodical manner to solve the problem of leaching.
- These are lined with materials that are impermeable such as plastics and clay and are also built over impermeable soil. Constructing a sanitary landfills is very costly.
- The process of burning waste in large furnaces at high temperature is known as incineration.
- In these plants, the recyclable material is segregated and the rest of the material is burnt and ash is produced.
- Burning garbage is not a clean process as it produces tonnes of toxic ash and pollutes the air and water.
- A large amount of the waste that is burnt here can be recovered and recycled. In fact, at present, incineration is kept as the last resort and is used mainly for treating infectious waste.
- It is a process of combustion in the absence of oxygen or the material burnt under controlled atmosphere of oxygen. It is an alternative to incineration.
- The gas and liquid thus obtained can be used as fuels.
- Pyrolysis of carbonaceous wastes like firewood, coconut, palm waste, corn combs, cashew shell, rice husk paddy straw, and sawdust, yields charcoal along with products like tar, methyl alcohol, acetic acid, acetone, and fuel gas.
- Composting is a biological process in which micro-organisms, mainly fungi, and bacteria, decompose degradable organic waste into humus like substance in the presence of oxygen.
- This finished product, which looks like soil, is high in carbon and nitrogen and is an excellent medium for growing plants.
- It increases the soil’s ability to hold water and makes the soil easier to cultivate. It helps the soil retain more plant nutrients.
- It recycles the nutrients and returns them back to the soil as nutrients.
- Apart from being clean, cheap, and safe, composting can significantly reduce the amount of disposable garbage.
- It is also known as earthworm farming. In this method, Earthworms are added to the compost. These worms break the waste and the added excreta of the worms makes the compost very rich in nutrients.
- Four R’s – Reduce, Reuse, Recycle and Recover.
Waste Minimization Circles (WMC)
- WMC helps Small and Medium Industrial Clusters in waste minimization in their industrial plants.
- This is assisted by the World Bank with the Ministry of Environment and Forests acting as the nodal ministry.
- The project is being implemented with the assistance of the National Productivity Council (NPC), New Delhi.
- The initiative also aims to realize the objectives of the Policy Statement for Abatement of Pollution (1992), which states that the government should educate citizens about environmental risks, the economic and health dangers of resource degradation and the real economic cost of natural resources.
- The policy also recognizes that citizens and non-governmental organizations play a role in environmental monitoring, therefore, enabling them to supplement the regulatory system and recognizing their expertise where such exists and where their commitments and vigilance would be cost-effective.