EES 360 Blog: Water Issues in India

            India experiences a wide range of water issues, each of which are unique to the region and communities being studied.  Estuaries and wetlands in India are highly impacted by human activity.  In an estuary constant mixing of fresh and marine water occurs; therefore plants and animals that live in these waters have adapted to a euryhaline environment, where salt is present in up to 35 parts per million concentrations.  Wetlands include any inland water body where water is spread over a large area.  In India, estuaries and wetlands exist as a valuable resource to communities, and are used as such, but such water sources are also abused and polluted by the people living around them.  

            Estuaries and wetlands can be a good source of food and potable water.  The main use of this land is for agriculture resulting in the common placement of paddy fields close to these water bodies if the species of rice has adapted to that environment.  However, for all their usefulness, these water bodies also can become dumping grounds for local people.  When solid waste is dumped into estuaries or wetlands, the waste accumulates and depth of the water decreases and the area of the wetlands shrinks until the region becomes like solid land.  Eventually buildings are constructed on these former water bodies, which attracts migrant workers who continue to contribute to the trash dumped in the water, further reducing the area covered by the water body.  The proximity to water becomes an attraction to settlers, but is detrimental to the water body because there are more people present to dump waste into the water. 

            Biologically, the pollution of water bodies has an adverse effect on the plant and animal life in the ecosystem. The banks of estuaries, wetlands, and other water bodies tend to attract various industrial companies because many industrial processes require copious amounts of water.  The proximity of a water body also provides a convenient place to dispose of industrial waste.  Thermal effluents from a power station can reach a temperature of 48 to 50°C.  Such temperatures can kill even the plankton in the water, preventing primary productivity.  A reduction in primary productivity can affect the entire ecosystem because other species depend on the plankton.  Finally industrial pollution of water bodies can result in health-related issues such as skin and gynecological problems for people who consume contaminated water.

            The effluents released by these industries contain toxic materials and heavy metals which can accumulate within aquatic plants and animals.  Biomagnification of these toxins can occur as smaller organisms that consume the toxins are eaten by larger organisms, which accumulate higher levels of the toxic material.  The loss of plants and animals due to pollution can be mitigated through the introduction of metallophilic plants, which accumulate and store heavy metals through a process called bioremediation

            The presence of elemental contaminants also reduces the quality of drinking water for humans.  In India, arsenic and fluoride are the major elements that pollute potable water.  These usually come from a geogenic source and are not the result of human actions.  Arsenic is a major issue in northeast India and results in skin, cardiovascular, circulatory, and respiratory illnesses, in addition to kidney and liver disease.  The presence of fluoride in water results in human health issues like dental and skeletal fluorosis.   Arsenic and fluoride can both be removed using proper filters, but the removal of these elements can be difficult owing to issues involved with disposal of the used filters and unwillingness of the people to use the filters.

            Other contaminants include iron, which has both natural and anthropogenic sources, and nitrate, which comes from fertilizer use. With the increased use of agrochemicals and fertilizers, nitrate contamination of shallow aquifers has increased.  The Cauvery river basin of South India is known as the “rice bowl” of India and this area suffers from a lot of nitrate contamination.  Increased presence of nitrates in the drinking water can result in serious health problems.

            Although India protects water bodies through the Pollution Control Board (PCB), there is no management or political will to enforce such regulations.  Non-governmental organizations (NGOs) also contribute to efforts to regulate pollution of water bodies.  However, without help from the government and support from the community, these organizations are only most effective at spreading awareness, and less effective at truly ending pollution.  In order to effect real change in Indian communities’ treatment of water bodies, the government will need to ensure that implementation of policy is carried out to the fullest extent.  This will require that the government involve the people in the formulation and execution of policy.

EES 360 Blog: Sustainability at Auroville

           Auroville is an experimental city founded in February of 1968 by Mirra Alfassa, known in Auroville as the “Mother.”  Alfassa was the spiritual partner of Sri Aurobindo who was heavily involved in the Indian nationalist movement and struggle for freedom.   Based on Aurobindo’s and her own spiritual beliefs, the Mother desired to establish Auroville in order to create a community dedicated to human unity.   She envisioned Auroville as a self-sufficient community where work was seen as a service and not as a means of livelihood.  Today Auroville is an alternative community run by Aurovillians, but the city has been overseen by the Indian government since it took over the project in 1980.  One of Auroville’s achievements is its emphasis on sustainability and being environmentally conscience.  These areas of focus are observed through the projects going on at the Earth Institute and Upasana.

The Auroville Earth Institute was founded in 1989 and emphasizes the research and development of earth-based technology as well as the promotion of the use of raw earth as a building material.  The research at the Earth Institute focuses on the use of local raw earth found at the building site as the building material, with minimal use of steel and cement in order to provide a technology that is sustainable and environmentally friendly.   Additionally research at the Earth Institute has resulted in the development of hollow interlocking compressed stabilized earth blocks that can be used to build disaster resistant housing. 

The aim of the Earth Institute is to promote raw earth as a building material that can be used in conjunction with other renewable energies and sustainable technologies to encourage environmentally friendly development.   The production of compressed earth bricks consumes about four times less energy and is four times less polluting than fired bricks; therefore the earth based technology promoted by the Earth Institute is energy and cost effective. 

Another objective of the Earth Institute is to educate people on how to build with material from the earth.  The training courses offered here have spread the use of earth as a building material to numerous people from all over the world.  Since these courses began in 1990, 6,908 people from 69 countries have undergone training.  The institute offers theoretical and practical courses in making the bricks and using them in construction projects. 

These blocks are made from local soil containing either 5% cement or lime to provide stabilization and are not fired.  Cement is used to stabilize sandy soil, while lime is used to stabilize clayey soils, although the use of lime lengthens the amount of time necessary to allow the block to harden.  The stabilized earth is slightly moistened and then compressed using a steel press.  Various shapes and sizes of bricks can be produced.  The brick press used to create these blocks was designed and produced in Auroville and is now sold all over the world.  The press uses 15 tons of pressure to make the blocks, which are given a three day initial covered curing and then spend one month drying uncovered in the sun.  The blocks are water resistant and various types of blocks can be made including interlocking earthquake resistant bricks and ferrocement - bricks reinforced with steel mesh and rebar. 

The use of compressed earth bricks is environmentally friendly in several ways.  The use of local material and production of such bricks on site will reduce production and transportation costs because there is no need to import materials over long distances, which leads to a higher cost of building.  Additionally the material is biodegradable.  Cement is the only additive to the soil and this is broken down by the biochemicals of the topsoil within ten to twenty years.  The production of these bricks also avoids the use of firewood, thus slowing the rate of deforestation.  Finally the sustainable nature of these bricks is contingent upon the good management of resources at the building site and effective monitoring of the brick-making process.

            Upasana is a design studio and social business located in Auroville that represents another aspect of Auroville’s commitment to sustainability.  Upasana began in the 1990s because the founders felt the need to give back to the community in South India.  Upasana conducts several projects designed to promote social responsibility or to provide livelihood to the underprivileged, while also preserving an aspect of Indian culture.  A few of Upasana’s projects also address the need to promote sustainable practices.  The Tsunamika project provides trauma counseling to victims of the 2004 tsunami by having women make tsunamika dolls.  These dolls are made using materials from industrial waste and provide livelihood to the women who make them.  In the Small Steps project, village women construct fabric bags with the goal of making people more conscious of their usage of plastic bags.  This project coincides with the Tamil Nadu government’s initiative to reduce plastic bag usage by charging extra money for them.  

Diwali, Trichy, and Tanjore

Last Wednesday was Diwali, the festival of lights, which is kind of like New Years, Christmas, and Thanksgiving combined.  The fireworks started early in the morning - I heard them at around 5 AM - and continued throughout the day.  Everyone in the group dressed up in traditional Indian dress and we went to Suresh's house for the day.  We set off a lot of fireworks, played with baby kittens, and ate a lot of food off of banana leaves.  We had dinner at MCC with the students from Davidson University who are also in Chennai studying.  They weren't nearly as cool as we are.  But I guess it was interesting to talk to them.

On Thursday we left for another long weekend trip to Trichy and Tanjore.  We saw the Rock Fort Temple before heading to the hotel and swimming.  On Friday we saw the Sri Rangam temple, Grand Anicut dam, and Brihadisvara temple on the way to Tanjore.  At Brihadisvara, Drew and I got swarmed by a bunch of Indian men who wanted to take photos with us.  I thought we would never be done with pictures.  So basically our group, not the temple, was the biggest attraction there.  :)  Saturday we went to a limestone mine and collected fossils, but not before we got lost about 5 times on the way.  We also stopped to see a petrified tree.  On Sunday we saw the Tanjore Palace, which has a museum and several halls with bronze sculptures.  Then we headed back to MCC on Monday.

After Tuesday's lecture a group of us took the train into Chennai to go to another mall that's different than the one we visited previously.  It reminded me of a place I've been to in Hong Kong...  Once Caitlin, Tori, and I found the FabIndia we were set for a while.  We also found a store selling funny t-shirts.

Today (Wednesday) the group visited the Family Life Institute that is part of MCC.  Among the various things that it does, the center has a school and also runs self-help groups for women to help them earn a living.  We helped out around the building.  My group organized a huge number of children's books.  Some of the children showed up even though they had a day off for rain and they sang and danced for us.  We also bought some pretty jewelry from gypsy women whose children go to the school.  

So I fell in a rice paddy...

...more on that later.

On Friday we took a day trip to Kanchipuram, which is a few hours away from MCC.  Our first stop was at a sari shop.  Several girls bought saris to wear for Diwali.  Sari buying is a really complicated process...first you have to pick out the actual sari that you want, then the blouse piece and skirt have to match.  Amazingly we got out of the store in about an hour and managed to buy saris for 10 girls.  We ate lunch at this really good vegetarian restaurant.  It might have been the best food I've had yet.  I shared cashewnut naan, cauliflower curry, and some kind of vegetable dumpling curry with Serena.

After lunch we stopped by a weaver's house and watched some men making wedding saris.  It was incredible to see them making the fabric by hand.  The machine was so intricate and complicated.  We also stopped by a potter's house and watched him throw pots and jars.  Some of the girls in the group tried their hand at throwing pots too.

Okay, now for the rice paddy story.
On the way back from the potter's we stopped to look at a rice paddy.  We were walking out on a small strip of solid ground and somehow I managed to slip in the ditch and fall into the rice paddy.  And then I fell in again while I was trying to get out.  I only got a little mud on my shoes, but after that I was pretty much done with looking at rice.  And apparently Suresh got a picture of it.  How nice of him.

The next stop was at the beedi (cigarettes)  maker's house.  Since I had no interest in smoking, I took pictures of the village kids.  They absolutely loved having their photos taken.  It was super cute.  Our final stop was to see a dance performance arranged by Suresh's in-laws.  It was pretty incredible.  I can't even imagine all the practice it must take to do that.  We finally got around to dinner at 9:00 and didn't get back to MCC until 1:00 in the morning.  All in all it was a pretty good day.

On Saturday we slept in and headed into the city of Chennai after lunch.  We stopped at a musical instrument shop and then we went to the mall.  It was pretty much like an American mall, but there was a weird mix of Western and Indian stores.

I'll try to get some pictures up later...

Pondicherry

On Thursday we left for a weekend trip to Pondicherry.  The first stop was at DakshinaChitra, a living museum of the culture and architecture of southern India.  We walked through various styles of houses and looked at cool old stuff.  It was a really neat way to display the culture of the area.  Much more interesting than walking through a normal museum. 

DakshinaChitra

After that we traveled to Crocodile Bank and looked at more species of crocodiles than I ever needed to see in this lifetime.  We also saw some snakes and turtles and other reptile-y things.  Then we went to a super fancy hotel and spent the afternoon in the pool, which was nice after walking around in the heat most of the morning.

Friday we saw the temples at Mamallapuram, which have been declared a UNESCO World Heritage Site.  The temples were really neat and each of the panels told a different story, but there were A LOT of them.  We also stopped at the Five Rathas (more temples) and Shore Temple.  That night we stayed at the Dune Eco Resort, which also had a nice pool. 

Temple at Mamallapuram

On Saturday we went to Auroville, which is a SUPER weird hippie attempt at a utopian society, although I'm pretty sure they wouldn't appreciate me calling it that.  It's a community dedicated to achieving human unity, which is a neat idea, but they're still kind of weird.  They call the woman who founded the community "the Mother."  If that's not creepy, I don't know what is.  They also have a giant golden ball where they do meditation.  We weren't allowed in.  It was also an  interesting place because there were so many different countries represented in the population living there.  I think it was more of a melting pot than the US.

Matrimandir aka completely unnecessary giant golden ball

They were doing some good things at Auroville.  We visited a place called Upasana, a social business that tries to help men and women gain livelihood.  That was nice.

On Sunday we went to the ashram of the man who inspired "the Mother" to build Auroville.  I think we saw his body and people were sitting around it.  We also got blessed by an elephant, which was...cool and sad.  After checking into the hotel in Pondicherry and eating lunch we went shopping all afternoon.

On Monday we visited Neyveli Lignite Mines, which I didn't think would be that interesting, but was actually pretty cool.  It was a huge open pit mine and we got to go into the mine and see the areas undergoing reclamation after mining. 

On Tuesday we saw Chidambaram, a really big temple and Pichavaram, a mangrove forest.  We got to ride on a boat through the forest, which was fun.  Then we came back to MCC.

"Even the weeds are pretty!"

The title is courtesy of Tori.  :)
Yesterday after class we visited an orphanage where the children are raised in a family setting.  They are placed with a mother and siblings and also participate in the larger community life of the orphanage.  The orphanage will continue to support them until they get married or become independent because they have a job.  It was an interesting way of running an orphanage that is so different from the way we normally think about orphaned kids.  On the way back from the orphanage, some guy on a motorcycle definitely tried to pick me up.  I said no.  (Don't worry mom, I wasn't in any real danger...there were other people around).  In the afternoon Caitlin, Brooks, Serena, and I tramped around campus.

We wanted to see the MCC farm, but it was closed, so instead we went exploring around the campus.  There was a lot of nature happening.  And a lot of bugs who decided I would be a tasty afternoon snack.  Which is unfortunate for me.

Today we went clothes shopping in the afternoon and stopped for some more soft drinks from the store on the way back.  Then Luke and I dragged a group of people through the chemistry building because we really wanted to see the labs.  Luckily we ran into the chemistry lab store room guy and he showed us around to everything.  We saw an organic/inorganic lab, a physical chemistry lab, and the chemical room.  It was pretty cool.  I miss chemistry a whole lot, so it was nice to see something familiar.    

12 people. 1 rickshaw. no big deal.

This morning was our first day of lecture.  That was cool.  After lunch we sat around for a long time and talked about how we needed to exchange money and buy some supplies at Pick and Pack (aka the convenience store) down the street.  .......four hours later we finally headed out to the bank.  We decided to go by auto rickshaw.  So naturally we piled 20 people into two rickshaws.  Naturally.

This is pretty much what they look like.  I think there were 12 people in ours.  Maybe.  Anyway, it was a lot of people in a tiny space.

We arrived at the bank safely, although I was kind of scared we were going to lose Katie, because she was barely inside.  But we made it.  It took forever to exchange all our money.  No surprises there.  So we were just chilling at the bank for a good hour and a half.  Maybe longer.  Fun fun.  Then we went for ice cream!  :)  Then we went to the store to get some shampoo and soap.  AND SPRITE.  I've really missed soft drinks the past few days, so that was nice.  And that's pretty much the day!

Introduction to India

Day 1:
We left for the Greenville airport at 7:30 on Thursday morning.  And didn't arrive in India until 4:00 Saturday morning.  Oh, the joys of flying.  First we had a 6 hour layover in the Dulles airport and I thought I might actually die of boredom.  Then we got diverted from landing in Chennai because a plane had skidded off the runway and they couldn't get it cleared in time.  So we took a surprise trip to Bangalore to get fuel.  And finally, 4 hours behind schedule, we landed in Chennai.  We didn't get to Madras Christian College until around 6, so we had a snack and Caitlin and I took a much needed nap.  (Which is why there are no pictures of me up yet, Megan).

After napping all morning, we wandered around campus.  We saw the trash heap.  That was lovely.  We also walked by the cricket fields and "we were so hot, we got whistled at" (quote courtesy of Caitlin).  The first of many whistles, I'm sure.  Later in the afternoon we went to a John Lennon tribute concert put on by the MCC students.  It was pretty awesome except I was so tired I almost fell asleep a few times.  And then we went to bed at 8:30 and slept for 11 1/2 hours.  "It was glorious" (also courtesy of Caitlin).  Except the bed feels like you're sleeping on a ream of paper.

Day 2:
After breakfast we all headed out to the market.  It reminded me a lot of markets in Malaysia except everything seems so much less permanent.  We saw some cows.  Traffic was scary - but kind of what I expected....crossing the street was....fun.  The best part was going in the air conditioned department store.  I forgot how awful the heat and humidity would be.  And how much I love air conditioning.  We came back from the market and Caitlin and I collapsed under the fan in our room.  In the afternoon we met our MCC "buddies" and they took us around campus.  Then we had dinner at the Principal's (aka the President of the college) house.

So to sum up: In the last two days, there's been lots of sleeping, we've taken a lot of showers, and we haven't done any homework.  Which, to borrow from Caitlin, is glorious.  

The Role of Selenium in Human Health

Humans contain roughly 20 mg of selenium distributed throughout the body (Combs, 2005).  The element is usually incorporated into proteins.  Due to the size similarities between selenium and sulfur atoms, selenium can be incorporated into amino acids, replacing the sulfur that naturally exists in sulfur-containing amino acids (Combs, 2005).  These selenoamino acids can then be integrated into a variety of proteins (Combs, 2005).  Two types of selenoamino acids exist.  Selenocysteine and selenomethionine are both incorporated into proteins, but only selenocysteine amino acids have a physiological function (Combs, 2005).  In the body selenium-containing proteins provide antioxidant protection, redox regulation, and thyroid hormone regulation (Combs, 2005).  The antioxidant properties of selenium are extremely important in counteracting diseases involving oxidative stress (Rayman, 2008).  Selenoproteins are also necessary to prevent neurological dysfunction and brainstem degeneration (Rayman, 2008).  

Selenium can play an influential role in a variety of health issues and disease states.  Studies have shown that addition of selenium in the diet can improve immune response even in healthy individuals (Rayman, 2008).  Through the use of animal models, researchers have shown that selenium supplementation may play an important role in preventing HIV from mutating to a more powerful and dangerous form, and it may be possible that supplementation is necessary because retroviruses deplete their host’s stock of selenium so they can incorporate it into their own selenoproteins (Rayman, 2008).  Selenium intake may also influence the reproductive health of men and women.  Men’s fertility can be improved and women’s risk of miscarriage and pre-eclampsia can be reduced by increasing selenium intake (Rayman, 2008).  Selenium may also have a role in the reduction of cancer risk.  Current research has suggested that selenium metabolites may prevent cancer by inducing apoptosis in cancerous cells and inhibiting tumor cell invasion (Combs, 2005; Rayman, 2008).  

The major species of selenium available in food determines what humans consume and accumulate within the body.  The available species of selenium also govern the element’s final destination and the body’s use of the element (Rayman, 2008).  For example, selenium obtained from broccoli (Se-methyl-selenocysteine) cannot accumulate in the tissues, nor does it have a significant physiological function (Rayman, 2008).  However selenomethionine which originates from cereals or yeast can accumulate in proteins and be stored for long periods of time, allowing it to be used to maintain selenium levels throughout the body (Rayman, 2008).

Selenium in humans may be derived from meat, shellfish, nuts, whole grains, beans, peas, lentils, or fortified breakfast materials (Combs, 2005).  Humans generally ingest selenium from plants.  The uptake of selenium by plants depends upon the amount present in the soil (Rayman, 2008).  The bioavailability of selenium to plants is controlled by concentration within the surrounding soil, pH and redox conditions, the amount of organic matter present, bacterial activity, and mineralogy among many other factors (Rayman, 2008).  Within the soil, selenium levels vary because organic matter, iron hydroxides, and clay minerals can bind selenium removing it from the cycle of uptake by plants (Rayman, 2008).  Additionally the particular species of selenium – determined by pH and redox conditions – present in soil affects the mobility of the element and bioavailability (Rayman, 2008).  Therefore high levels of selenium in soil do not always result in selenium-rich crops, because the element may not be present in a form that can be used by the plant (Rayman, 2008).  

Different plant species vary in the efficiency of their uptake of selenium.  Some plants that accumulate selenium in significant amounts include Brazil nuts, broccoli, cabbage, garlic, and onions, all of which can contain up to 40,000 μg Se/g dry weight (Rayman, 2008).  Cereals like wheat, oats, rye, and barley are non-accumulating crops; therefore they uptake relatively small amounts of selenium, no more than 100 μg Se/g dry weight (Rayman, 2008).  The amount of selenium present in foods varies by country and region from excessively toxic amounts to inadequate quantities.  Countries such as the United Kingdom, where selenium levels are low in plants, have begun supplementing animal feed with the element to increase human intake (Rayman, 2008).  

Humans can suffer from both a deficiency in selenium and an excessive intake of selenium.  Insufficient levels of selenium can cause cardiomyopathy, the deterioration of the heart muscle, possibly in conjunction with the mutated Coxsackie virus (Rayman, 2008).  This condition, known as Keshan disease, is mainly prevalent in north-east China, however the cardiomyopathy of some Western patients has been associated with a lack of selenium in the intravenous nutrients provided (Rayman, 2009).  Selenium toxicity is much less common than deficiency and symptoms of excessive selenium intake include hair loss, and brittle, thickened and stratified nails (Rayman, 2009).  Chronic ingestion of high levels of selenium may lead to skin rash, weakness, tingling sensation, and diarrhea (Combs, 2005).  Therefore selenium, like most nutrients must be consumed in the proper amounts or health problems could ensue.  However the determination of a recommended daily intake of selenium is difficult due to the numerous factors that influence regulation of the element (Rayman, 2009).  Advisory bodies must weigh both the benefits and the risks in order to determine an appropriate threshold level of intake.

References:

Combs, G.F. (2005) Geological Impacts on Nutrition. In Stone, D. Essentials of Medical Geology. Elsevier.

Rayman, M.P. (2008) Food-Chain Selenium and Human Health: Emphasis on Intake. British Journal of Nutrition. 100, 254-268.

Energy, Climate Change, and Health

          Energy production and use is both detrimental and beneficial to human health.  Although the availability of energy sources may provide electricity for cooking, communication, and industry, the process of producing energy can negatively affect a population through environmental pollution and hazards of the production process (Wilkinson, Smith, Joffe, and Haines, 2007).  Lack of energy security is a growing problem that, in addition to global climate change, will disproportionately affect the health of the poor, because the burden of reduced energy supply and climate change generally falls on those that are already lacking in resources (Wilkinson, et al., 2007).  For example, climate change may affect monsoon rainfall or glacial melt in India, thus changing the availability of water to populations – especially agricultural communities – that depend on it.

Due to India’s large population, the country contributes around 4% to global carbon emissions (Arora, Busche, Cowlin,  Engelmeier, Jaritz, Milbrandt, Wang, 2010).  Considering the vast number of health and environmental effects of climate change to due greenhouse gases, India has declared that it will not allow the country’s per capita greenhouse gas emissions to exceed that of an industrialized country.  Currently India emits around 1 ton of CO₂ per person compared to the 10-20 tons of CO₂ emitted per person in industrialized countries (Arora, et al., 2010).  These efforts are important when considering that the effects of climate change go beyond the immediate concerns of water, land, and air pollution.  Increasing temperatures that result from climate change may stimulate increased numbers of heat waves, which are extremely dangerous in all areas, developed or not, but especially of concern to countries where the ability to adapt to such temperature changes may be extremely restricted due to low income (Wilkinson, et al., 2007).  The world will probably also see an increase in the number of extreme weather events like severe storms, floods, and droughts (Wilkinson, et al, 2007).  Rising sea levels, a result of the melting of glaciers and expansion of the seas, will increase seawater intrusion into coastal freshwater and will result in the displacement of large coastal populations.  Additionally water, food, and vector-borne diseases might undergo changes in disease pattern and frequency (Wilkinson, et al., 2007).  

            Human energy use is almost exclusively focused on the use of fossil fuels as energy sources and there are extensive health risks associated with the extraction, production, and use of these fuels.  Of the total world energy use, about 80% is based on fossil fuels (Wilkinson, et al., 2007).  India accounts for 3.8% of the global consumption of energy, with the country’s focus being on coal and oil energy sources (Arora, et al., 2010).  

World Energy Use in 2001

Worldwide Consumption of Energy Sources by Country

Biomass fuel represents 10% of the world’s energy use and is extensively used as a traditional fuel source in developing countries (Wilkinson, et al., 2007).  Both fossil fuels and biomass contribute to substantial human health risk and the development and use of clean energy sources will be important in reducing both climate change and energy-related health hazards.  The combustion of biomass and fossil fuels results in airborne pollutants, which pose a significant risk at the household, community, regional, and global levels (Wilkinson, et al., 2007).   

Although fossil fuel combustion contributes the most to environmental pollution, the 2.4 million people worldwide who depend on biomass as a household energy source are more likely to suffer from pollution exposure due to biomass fuels (Wilkinson, et al., 2007).  In India, about 40% of the total energy supply consists of fuel such as wood and cow manure, which is mainly used in rural households for cooking and heating water since the availability of electricity in rural areas is low (Arora, et al., 2010).  Because the technology used to burn the fuel is not very advanced, a high concentration of smoke builds up indoors, often resulting in indoor air quality far worse than international standards on air pollution (Wilkinson, et al., 2007).  Chronic exposure to indoor air pollution results in a number of health issues including respiratory infections, lung and other cancers, tuberculosis, low birth weight babies, and potentially asthma and heart disease (Wilkinson, et al., 2007).  In southeast Asia, thirty-seven percent of the burden of disease can be attributed to indoor air pollution, especially among impoverished populations that cannot afford clean fuels and proper ventilation (Wilkinson, et al., 2007)

            India has begun using biogas to provide energy to small rural areas that are not connected to the grid and thus do not receive electricity.  Biogas is a product of the digestion of organic material like animal waste, crop residues, and industrial and domestic waste, a process which releases methane, a combustible gas (Arora, et al., 2010).  About four million family-size biogas-generating plants have been installed around the country and are used to provide energy for cooking and lighting in rural areas (Arora, et al., 2010).  Larger production plants can be installed to serve entire villages.  The majority of the biogas is generated from cattle manure, and given that India has 28% of the world’s cattle population, this alternative to biomass burning may be a highly useful and productive source of energy in rural areas (Arora, et al., 2010).

            There is no doubt that the development and distribution of energy sources that began during the industrial revolution has vastly improved the health of the world’s people.  However both the lack of clean energy and the climate change resulting from burning of fossil fuels can be detrimental to human health.  It is important that countries seek alternative fuel sources and improve existing energy technologies in order to ensure the health of their populations both today and for the future.

 References:

Wilkinson, P., Smith, K.R., Joffe, M., Haines, A.  (2007). A Global Perspective on Energy: Health Effects and Injustices. The Lancet 370(9591), 5-18.

Arora, D.S., Busche, S., Cowlin, S., Engelmeier, T., Jaritz, H., Milbrandt, A., Wang, S. (2010). Indian Renewable Energy Status Report.

 

The Epidemiological Transition in India

Recent evidence has emerged suggesting that developing countries are experiencing significant increases in non-communicable diseases (NCDs), especially among the poor and low-income populations (Shetty, 2002).  In developing countries about 40% of all deaths can be attributed to NCDs (Shetty, 2002).  Urban development and industrialization in these countries facilitate lifestyle and diet changes that can have a serious impact on populations that did not previously suffer from NCDs (Shetty, 2002).  India is no exception to these changes as it undergoes huge demographic transformations that vary across the states and regions.  An epidemiological transition is occurring as “complex changes in patterns of health, disease, and mortality” promote a shift from infectious diseases to non-communicable illnesses as the major driver for morbidity and mortality (Shetty, 2002).  India is currently undergoing this epidemiological transition and thus is dealing with both infectious disease at the poorest levels of society and chronic, non-communicable diseases in the upper levels of society. 

Some interesting studies have been done with migrant populations to understand the impacts that genetics and environment can have on an individual’s development of NCDs.  It has been shown that as migrants adopt the social and cultural lifestyles of their new environment, they develop disease patterns that resemble those of the local people (Shetty, 2002).  These environmental and behavioral changes may also expose pre-existing genetic disposition to certain NCDs that was not evident in the migrant’s previous lifestyle and location (Shetty, 2002).  Therefore the change in environment can have a direct impact on people who are intrinsically predisposed to have the illness.  For example, populations that have migrated to the United Kingdom from India have developed a high risk for coronary heart disease.  Despite the fact that the South Asian populations studied have plasma cholesterol levels below the national average in the UK and that their total and saturated fat intakes are no different from the national average, these people are at an increased risk for heart disease (Shetty, 2002).  This propensity to develop coronary heart disease may be due to a change in diet, lifestyle, or physical activity that occurred upon their migration to the UK (Shetty, 2002).  When ethnic populations have a disease-risk pattern that deviates from the indigenous population, it is likely that this variation is due to environmental aggravation of genetic predisposition (Shetty, 2002).  The increased risk of NCDs associated with migration is not just limited to international transitions, but may also be found in internal migration or areas undergoing urbanization (Shetty, 2002). 

Obesity and its related problems like high cholesterol are increasing in India due to the changing lifestyles and standards of living brought about by urbanization.  It is possible that malnourished children may be more at risk for obesity.  If a child undergoes several episodes of nutrient deprivation followed by rehabilitation, there may be a “discordance between linear growth and adipocyte development” that encourages the growth of fat cells at the expense of the child’s height, which is limited by the lack of nutrients (Shetty, 2002).  In addition childhood obesity is affected by decreased physical activity, especially in urban Indian cities where there is increased food intake along with an increase in sedentary lifestyles (Shetty, 2002).  Although adult obesity is less well studied, the Nutrition Foundation of India found that there were higher rates of obesity among the higher socio-economic classes and very low rates among the population living in urban slums (Shetty, 2002). 

The changing food consumption patterns in India are contributing to increasing prevalence of NCDs.  Although there has not been a significant increase in energy intake, there has been an increase in the amount of energy from fat that Indians are consuming (Shetty, 2002).  Between the years of 1975 and 1995, there was a decrease in the intake of cereal grains that was offset by the intake of milk products and animal fats (Shetty, 2002).  Traditionally pulses and legumes have been the source of protein in the Indian diet, but these animal proteins have superseded these foods (Shetty, 2002).

Chadha, Gopinath, and Shekhawat conducted a study to understand how the lifestyle, dietary, and physical activity patterns that accompany urbanization affected the prevalence of coronary heart disease in India (1997).  The study found that the prevalence of clinical coronary heart disease was 31.9 per 1,000 in urban areas compared to 5.9 per 1,000 in rural areas (Chadha, et al., 1997).  An examination of the risk factors for heart disease – hypertension, diabetes, obesity, family history, and smoking – shows that they follow the same pattern of high prevalence in urban areas (Chadha, et al., 1997). Sodium and alcohol consumption were also higher in urban than rural areas (Chadha, et al., 1997). 

The high rates of coronary heart disease risk factors in urban areas are most likely due to a sedentary lifestyle (Chadha, et al., 1997).  In contrast, rural men and women are more likely to be involved in the physical labor of agriculture (Chadha, et al., 1997).  A study cited by Chadha et al. found that urban populations were 2.5 times more likely to have coronary heart disease than rural populations (1997).  Chadha et al. also attribute the prevalence of coronary heart disease in urban populations to the considerable air pollution present in cities.  Pollutants like oxides of nitrogen, sulfur dioxide, and suspended particles are strong inducers of the buildup of fats and cholesterol in arteries (Chadha, et al. 1997).  This study of the increased prevalence of heart disease in urban areas is one example of the epidemiological transition occurring in India.  As more of the country urbanizes and populations change their lifestyles, there will be an increasing number of individuals suffering from chronic, non-communicable diseases, like heart disease.  

References:

Chadha, S.L., Gopinath, N., & Shekhawat, S. (1997). Urban-Rural Differences in the Prevalence of Coronary Heart Disease and its Risk Factors in Delhi. Bull. World Health Org. 76(1): 31-38. 

 

Shetty, P.S. (2002). Nutrition Transition in India. Public Health Nutrition 5(1A): 175-182. 

Nitrate Toxicity in Humans - Methemoglobinemia

Drinking water that contains high levels of nitrates can be toxic to humans.  Nitrate present in the environment comes from a variety of sources: 25% is derived from the atmosphere, while the rest comes from the geology of the area and human activities such as fertilizer use and ejection of sewage and industrial waste into water sources (Gupta, Gupta, Chhabra, Eskiocak, Gupta, and Gupta, 2008).  The nitrates present in humans result from consumption of meat, nitrate-rich vegetables and fruits, and water, but nitrate may also be produced by endogenous pathways (Gupta, et.al., 2008).   Excessive intake of nitrate is toxic to humans and may result in any number of health issues, including cancer, chronic diarrhea, detrimental changes in the respiratory and cardiovascular systems, and other effects (Gupta, et.al., 2008).

Consumption of excessive amounts of nitrates can also result in a condition known as methemoglobinemia, which starves the body’s tissues of oxygen.  As the body processes nitrate (NO₃^-), it is reduced to nitrite (NO₂^-) (Gupta, Gupta, Seth, Gupta, Bassin, and Gupta, 1999).  Therefore nitrate’s toxic effect depends on the amount present in potable water and on the reducing conditions present in an individual’s body (Gupta, et.al., 1999).  The reduction of nitrate is facilitated by bacteria that require a high stomach pH (pH greater than 4) in order to grow (Gupta, et.al., 2008).  Nitrate is reduced to nitrite in the oral cavity and intestinal tract, and upon reentering the bloodstream is converted back to nitrate (Gupta, et.al., 2008; Gupta et.al., 1999).  The process of converting nitrite in the blood back to nitrate directly oxidizes the ferrous ion (Fe²⁺) of hemoglobin to a ferric ion (Fe³⁺) to create methemoglobin (Gupta, et.al., 1999).  The image below shows the structure of hemoglobin, with the red and blue areas representing the different subunits of the protein.  The green structures represent heme groups, which contain the iron involved in the process described above.  The normal function of hemoglobin is to carry oxygen to various tissues throughout the body (Dugdale, 2010). 

The structure below is the most common type of heme group.

Methemoglobin has the same structure as that of hemoglobin.  The only exception is that the iron exists in a different oxidation state.  Upon oxidation to methemoglobin, the body naturally restores the hemoglobin through a process involving cytochrome b₅, an electron transport protein, as shown in the reaction below where Hb³⁺ is methemoglobin and Hb²⁺ is hemoglobin (Gupta, et.al., 1999).

 The enzyme cytochrome-b₅ reductase then restores the oxidized cytochrome b₅ to its original state (Gupta, et.al. 1999).  

In summary, ingested nitrate is converted to nitrite, which is then converted back to nitrate and in the process oxidizes hemoglobin to methemoglobin.  The methemoglobin is restored to hemoglobin by the protein cytochrome b₅.  Finally the cytochrome-b₅ reductase enzyme returns the now oxidized cytochrome b₅ to its previously reduced state.

In cases where nitrate levels are too excessive or the cytochrome-b₅ reductase system is weakened, the cytochrome-b₅ reductase enzyme reserves become exhausted and methemoglobin accumulates in appreciable levels in the blood (Gupta, et.al., 2008). The presence of high concentrations of methemoglobin in the blood can prevent oxygen from being delivered properly to tissues. When more than 10% of hemoglobin is present as methemoglobin, blue discoloration of the skin is evident, and if greater than 60% of hemoglobin has been oxidized, death results (Gupta, et.al., 1999).

Gupta, et.al. reported that the cytochrome-b₅ reductase system is able to accommodate and reduce amounts of methemoglobin in the blood until the levels of nitrate in drinking water reach about 95 mg/L (1999).  The activity of cytochrome-b₅ reductase then declines until it returns to normal levels at around 200 mg/L of nitrate in drinking water (Gupta, et.al., 1999).  This decline in cytochrome-b₅ reductase activity is correlated with an increase in nitrate concentration in the water and methemoglobin concentration in the blood (Gupta, et.al., 1999).  The enzyme’s ability to compensate for increasing levels of nitrate worked best for children age one to eighteen (Gupta, et.al., 1999).  Infants and adults in this study had poor cytochrome-b₅ reductase response to increasing levels of nitrate and methemoglobin, which may be due to the incomplete development of the reductase system in infants or a saturation of the system in adults (Gupta, et.al., 1999). Infants are also more likely to be affected by nitrate due to a higher stomach pH, which encourages growth of nitrate-reducing bacteria (Gupta, et.al., 2008).   

The World Health organization sets the maximum limit of nitrate ion in drinking water at 50 mg/L (Gupta, et.al., 1999).  The Bureau of Indian Standards sets the limit slightly lower at 45 mg/L (Gupta, et.al., 1999).  Despite the intentions of these regulatory institutions, people in India are still frequently exposed to levels of up to 500 mg/L of nitrate in their drinking water (Gupta, et.al., 1999).  The populations most affected by methemoglobinemia are infants and people older than 45 years (Gupta, et.al., 2008). 

Cleaning up the extremely high levels of nitrates present in drinking water is expensive and not cost-efficient (Gupta, et.al., 2008).  Since this is the case, governments need to focus on solutions that will decrease anthropogenic contributions to natural nitrate levels in water.  The use of nitrogen containing fertilizers should be reduced to keep too many nitrates from washing into drinking water sources (Gupta, et.al., 2008).  Individuals should also limit the use of antacids, as this will raise stomach pH and encourage the growth of nitrate-reducing bacteria (Gupta, et.al., 2008).  Governments must also focus on educating people on the health effects that can result from excessive nitrate consumption (Gupta, et.al., 2008).  Gupta, et.al. recommend that additional research needs to be done to better understand the toxicity of nitrate compounds and what levels of nitrate are safe for drinking water (2008).

           

References:

Gupta, S.K., Gupta, R.C., Chhabra, S.K., Eskiocak, S., Gupta, A.B., and Gupta, R. (2008). Health Issues Related to N Pollution in Water and Air. Current Science. 94(11): 1469-1477).

Gupta, S.K., Gupta, R.C., Seth, A.K., Gupta, A.B., Bassin, J.K., and Gupta, A. (1999). Adaptation of Cytochrome-b₅ Reductase Activity and Methaemoglobinaemia in Areas with a High Nitrate Concentration in Drinking-water.  Bull. WHO. 77(9): 749-753.

Dugdale, D.C. (2010). Hemoglobin. Medline Plus. http://www.nlm.nih.gov/medlineplus/ency/article/003645.htm

Image Sources:

http://en.wikipedia.org/wiki/Hemoglobin

http://en.wikipedia.org/wiki/Heme