An explosion in the popularity of hair extensions - fuelled by celebrities like Beyonce, Kim Kardashian and Victoria Beckham - has seen huge numbers of women and teenagers across Russia selling their locks for a relative pittance to feed a booming industry in human hair.

In an exclusive investigation, MailOnline has followed the path the hair from the heads of struggling Russian women and children, through the treating and processing plants in tyrannical Uzbekistan and war-ravaged Ukraine, before it is sold to Western women in upmarket salons in Britain and the US.

In 2013, £42.8million worth of human hair was imported - 80million miles of hair - or enough to go around the world more than 3,200 times. In America quantities are far higher.

Known for its strength, quality and colour, Russian hair is seen as the best in the market and far superior to rival countries Brazil, India, and China, where the hair market is also thriving. 

High levels of demand for the best 'virgin' Russian hair - that has not been treated with chemicals or dye - has led to fears that children and teenagers have been targeted by unscrupulous dealers as the industry becomes an increasingly big and ruthless trade. 

One seller told MailOnline that business is so good, his firm now employs 350 people to cope with demand. 

He dismissed suggestions that the industry takes advantage of vulnerable people, insisting young women cut their hair voluntarily - but a fashion expert hit back, arguing girls 'sell their hair because they don't have any other choice'.

Former Spice Girl Victoria Beckham, who is said to spend £25,000 a year on hair extensions, once joked that she had 'Russian cell-block H' on her head from hair taken from prisoners. 

Our investigation shows that that old stereotype is now considered off the mark, as is the perception of claims of hair from the dead sold by mortuary workers.

Instead thousands of traders travel across Russia's 13 time zones hosting 'cutting session' fairs in remote towns and cities for those ready to part with their hair for roubles by posting up adverts on lampposts in the places they travel through and on the internet.

Model and wedding photographer Daria Dangilova, 24, is just one of the women who traded in her 'dark, soft, well groomed' mane to fuel the West's insatiable demand for real hair. 

She received 9,500 roubles - around £120 - when she had lopped off in Moscow last week, but her hair will sell for many times more in the salons of London and New York.

Daria received a good price for her hair compared with many Russian girls and women who sell out of desperation - a trend that prompts fears that the trade, while legal, amounts to alarming exploitation of the poor to benefit the rich.

Wealth inequality in Russia in one of the highest in the world - while the federation has around 100 billionaires, around 18 million people live below the poverty line. 

Daria told MailOnline she had long hair all her life, and bartered with dealers to get the best price after she was offered just 2,000 roubles, or £25, for her 190 grams of luxuriant hair.

'As it was being cut, I became scared. I started thinking, why am I doing it? I almost burst into tears but by then it was too late to turn back', she said.

'To be honest, my mother was shocked, but eventually she supported me, and even came with me to cut the hair and sell it. She said, if I have decided this is what I would do, she'd support me.' 

More than 10 years since Siberian schoolgirl runaway Valentina made headlines when she and her three friends, all aged between 11 and 13, sold their hair to pay for their next meal, MailOnline tracked her down for an interview.

Valentina, now 24 and a happily married mother-of-four, watched as a friend sheared her 14-inch hair with a pair of rusty scissors before it was sold to a dealer for a paltry 70 roubles, just £1.40.

After returning to her mother, Valentina realised they had been conned by 'sharks', and felt ashamed at pawning her hair - but said at the time she was desperate and the money paid for her and her friends meals for several days.

'It wasn't the easiest day of our lives when me and my friends went to sell our hair,' she recalled.

'We were in trouble with our parents, we'd been stupid to have run away from home, and at this point were scared to go back - but there was no food to eat as we wandered the city in the February cold.

'We noticed the 'Buy hair, pay lots' announcement stuck to a lamp post and thought this should provide us with good money.

'I remember we were were scared to cut our hair, and then sooner or later face our parents. But our hunger was stronger than our fear. Looking back, I understand how paltry was the money this dealer paid us.'

A caring adult, seeing the girls in such a plight, might have helped them back to their parents, or into the hands of social workers or a charity, rather than paying them a derisory sum for her hair to stay on the streets.

'The only thing that buoyed me afterwards was the rumour that my hair had gone to England, perhaps onto the head of someone famous like Victoria Beckham', she added.

'But when you are so young you only think about the immediate problem, and that time it allowed us to buy food.'

The dealer who bought her hair, Olga, said women who sell their hair to her can feel 'ashamed'.

'I see so many sad girls and women as I travel around Russia buying hair', she said. 'I would say a quarter of all the people who bring their hair to me are distraught. Some are upset because their hair is unsuitable; others don't want to sell their femininity for a few roubles, and feel ashamed. 

'I always carry a box of tissues along with my weighing-scales and tape-measure.' 

Dealers are also active in the economically-struggling Crimea, annexed by Vladimir Putin's military forces last years.

Ekaterina works the patch, publishing 'before and after' images of her clients, and holding up locks of hair like a hunter clutches his trophies. She promises local females - 'I will buy - and sell - your hair.' 

Fashion historian and author Caroline Cox, from Stalybridge, Lancashire, said the sale of human hair was tantamount to exploitation.

While the use of human hair as extension has always been popular, she said the industry is bigger than it has ever been because people no longer hide about their use.

'The use of hair extensions was huge in the late 19th and early 20th century, it was massive before women began to get their hair cut short in the twenties', she told MailOnline.

'But now the trade is bigger than it has ever been. It really infuriates me when people say women choose to sell their hair, when really they sell it because they don't have any other choice.

'In cultures in Russia and India, particularly Slavic cultures, that say long hair is beautiful, why would women choose to cut it off unless they had to? 

'There is little regulation of the industry, and there are still instances where hair is forcibly cut, people are mugged for their hair or it is shaved as punishment. 

'It's my opinion that people who buy human hair extensions don't care where the hair is coming from, and don't make the link between market supply and demand.' 

A dealer from Bashkortostan, on the western edge of Siberia, set out the price list for hair sales in her posting.

Dark hair of 70cm in length sells for 2,500 roubles (£32) per 100 grams. The same length and weight of dark brown hair sells for 3,000 roubles (£38). Light brown gets 3,500 roubles (£45).

These dealers send the hair to wholesalers and hair processors like Natural Human Hair Company, run by 33-year-old Alexander Kalendarev, who swapped a profession as a doctor to sell 'virgin' hair, or 'Slavyanka' sourced in Russia.

Speaking from the heart of his multinational operation in Uzbekistan, he employs 350 staff in a number of factories who are tasked with cleaning and preserving the hair for well-off women, thousands of miles from the dusty streets of this central Asian dictatorship. 

(dailymail.co.uk)