In the blazing morning sun the hour-long walk along the busy road left Revathy exhausted. She wiped sweat from her face and sat quietly for a while before opening her shop. 'I'm struggling for a livelihood the same way today as I did before I sold my kidney. I cannot afford to travel by bus. I need to walk 8km every morning and evening to run this shop,' said the 27-year-old mother as she swept the floor of the ramshackle tin and mud structure on the edge of a slum in Chennai.
Ms Revathy's story is one of loss and desperation. Weeks after her labourer husband left her for another woman, Ms Revathy saw her home in the seaside slum of Kasimedu destroyed by the Asian tsunami that struck in 2004.
Seeking shelter at a nearby tsunami refugee colony, Ms Revathy and her two small children were given a one-roomed shanty and some government aid to start a small business. Soon she found herself in new miseries as many fellow tsunami refugees, after buying garments from her, failed to pay instalments and she was forced to borrow money from private lenders.
It was then that a woman named Shanthi, a kidney broker who lived in a nearby slum, suggested she sell one of her kidneys. Ms Shanthi had done so herself several years previously, to meet the expenses of her daughter's marriage.
'Use 75 per cent of the money to clear the debt, and with the rest open a small shop, to save your family from hunger and death,' she told Ms Revathy.
Ms Shanthi then introduced her to another broker in the chain and the deal was struck. In June last year, in Chennai's Kaliappa hospital, Ms Revathy's right kidney was removed and sold to a 47-year-old Chennai businessman suffering from irreversible kidney failure.
Ms Revathy's story reflects the booming Indian organ trade that, since the Boxing Day tsunami, has found its heartland in the southern state of Tamil Nadu and its capital Chennai. Health activists in India estimate that 4,500 kidneys are transplanted every year, with about two-thirds being sourced illegally - bought from poorer people, most of who are sucked into the deals by wealthy organ brokers and their network of contacts that extends to the slums and remote villages.
They recount stories of men and women - many of whom have sold their kidneys in the past - working as part of the supply chain targeting the poor in debt-ridden areas such as the tsunami-struck southeastern coastline. Loan sharks sometimes introduce their debtors to the organ brokers to recoup their money.
The selling of kidneys is illegal in India unless it comes from a relative, so brokers pass off the donor as a cousin of the patient. In Ms Revathy's case, the brokers took a government-issued identity card of the patient's cousin and replaced her photo with Ms Revathy's.
Ms Revathy received 50,000 rupees (HK$9,000) for her kidney.
The illicit trade led the Indian federal government to introduce the Transplantation of Human Organs Act (THOA) in 1994, enforcing the monitoring of all organ transplants.
To help implement the THOA rules, all states set up Transplant Authorisation Committees (TAC). Without TAC approval neither a relative nor an unrelated person can donate a kidney. But both the TACs and the enforcement of the act have failed miserably throughout the country, with Chennai emerging as the illegal kidney transplant capital of India in the past decade.
As authorities stepped up action against the trade, Tamil Nadu health minister K.K.S.S.R. Ramachandran cancelled the organ transplantation licences of two top Chennai hospitals after they were caught forging kidney transplant orders. He announced this week that similar forgery cases involving 13 other hospitals were being investigated, while all 54 hospitals licensed to carry out organ transplants were being watched closely.
'In the past 13 years in Tamil Nadu, since the THOA came into force, 8,000 kidneys have been donated and at least 65 per cent of them are from unrelated poorer donors who sold their kidneys because they were in desperate need of money,' said Palanisamy Muthupandian, an executive of Chennai-based NGO Community Health Education Society (CHES).
'When organ brokers found that TAC in Tamil Nadu was sometimes blocking donations because [TAC] was not convinced the unrelated donors were affectionately attached to the recipients, many of them began forging identity documents to present unrelated donors as blood relatives [of the recipients], as they did in the case of [Ms Revathy].
'Organ brokers are helping at least 70 per cent of all unrelated donors masquerade as blood relatives [of the kidney recipients] these days,' he said.
Poverty drove Ms Revathy to sell her kidney. 'I was desperate to be rid of the pressure of mounting interest on the loans and those hounding money-lenders,' she said. 'As soon as I got the money I spent 35,000 rupees to pay off the debts. Using 8,000 rupees I bought household materials, clothing for family and a stock of food for some months. And with about 5,000 rupees of capital I opened this shop.' She sells grocery items and cheap cosmetics in her shop and clears about 2,500 rupees a month.
'Despite selling my organ I have not been able to get rid of hardship in my daily life. I think selling the kidney was a mistake,' Ms Revathy said as she lifted the folds of her sari and ran her palm over the 35cm scar across her midriff.
After Ms Revathy's case was brought to the attention of authorities, health workers in the village of Ernavur, 20km outside Chennai, found about 100 cases of kidneys sold by poor fishermen and their families.
'The actual figure for the kidney donors is at least three times as much and 98 per cent of those who have done so are women,' said Maria Selvam, chief of Ernavur's fishermen's association.
'While about 20 per cent of us own boats, the rest of our fishing community is made up of daily wage fishing labourers. We as fishermen are used to living close to our boats. But we have been provided housing 10km away from our fishing harbour now. Unable to afford to commute daily from Ernavur to the harbour, most fishing labourers are not going to sea, pushing families into hardship. With the men not working, women are coming out of the home to earn money. Those in a desperate situation are selling their kidneys,' Ms Selvam said.
Growing reports of the trade have led to recent pressure from political quarters and forced police to probe more deeply into the sale of kidneys by tsunami survivors.
'After police launched investigations into kidney sales in Tamil Nadu in recent weeks, the brokers have gone underground and the deals have become more discreet,' said a senior police officer in Chennai.
'In this situation, brokers are ... paying even less to the kidney sellers, which means further exploitation of the donors and fatter cuts for the brokers.'
Some observers are suggesting that parting with an organ for money - since it does not endanger the donor's life - is not wrong and to stop the illegal trade the best step is to legalise the business.
Pinakapani Manorama, the chief of Chennai medical aid group CHES, said that if the trade were legalised, prospective donors and recipients of the kidneys would be able to meet in the open, with the donor benefiting in many ways.
'A broker tries to buy a kidney at the cheapest price and sell it at the highest,' said Dr Manorama.
'If the trade is legalised, every deal will become transparent, the middleman won't be required and a donor will get a price two to three times more than the present rate. It is not easy to stop the poorer people from selling their kidneys - but at least we can help them get more benefit for their service.'
A member of the TAC in Tamil Nadu indicated some degree of support for the trade. 'Hundreds of kidney patients are waiting in the queue and supply is always far less than the demand. Organ donation after death is almost non-existent in India. This illegal kidney trade, in fact, offers a lifeline to those patients who have no hope otherwise,' said the TAC member.
'We know all the documents [showing that donors are blood relatives or unrelated but affectionately attached to recipients] we see are false and it is an open secret. If we don't approve a transplant on those forged documents we know a patient would die soon. So, on humanitarian grounds we clear all applications with our eyes closed.'