Could blockchain technology solve the global problem of food fraud? Rahul Tandon reports on a meat scandal in India and Manuela Saragosa speaks to Jessi Baker, the boss of Provenance, a company that uses the blockchain to make supply chains more transparent, and to Chris Elliott from the Institute for Global Food Security at Queen's University in Belfast in the UK.

(Photo: Cow farming in the UK, Credit: Getty Images)

Coal fires used to beat the bitter cold of Mongolian winters blanket capital city Ulaanbaatar with smog in the winter, the BBC's Roger Hearing finds, when he meets residents from the Ger District.

Typical sanitation is makeshift and in the form of latrines, says Choikhand Janchivlamdan, a sanitation expert at the Green Initiative. This can lead to the spread of disease. Lost livestock due to harsh winters and a desire for better education is leading people to the city, she says. As people move to the city from the countryside, the problem gets worse as no new sewage systems are built.

Tserenbat Namsrai, Mongolia's environment minister, plans to introduce smokeless fuel in a bid to combat pollution and introducing more electric heating.

Robert Ritz, a US professor who lives in the city, says PM2.5 particulates - that's atmospheric particulate matter that have a diameter of less than 2.5 micrometres - kill thousands of people per year.

Two companies dominate the global eyewear industry - and now they are merging into a glasses behemoth. What does it mean for the bespectacled public?

Manuela Saragosa investigates the story behind these two anonymous giants - Italian fashion frames designer Luxottica, and French lens-maker Essilor - with the help of American eyewear retail pioneer E Dean Martin, and Gordon Ilett of the UK's Association of Optometrists. And she asks the European Commission why they were happy to wave through their merger earlier this year. Producer: Laurence Knight.

Producer: Laurence Knight

(Picture: Glasses model frames - black silhouettes isolated on white; Credit: Alxyzt/Getty Images)

The gigantic Oyu Tolgoi copper mine will certainly make some people rich, but how many of them will be Mongolian?

Ed Butler speaks to the BBC's Roger Hearing, who is at the mine, fresh from taking a taxi ride hundreds of metres below ground. He has been delving into who will profit more from this vast project in the middle of the Gobi Desert - the Mongolian state or mine operator Rio Tinto. Meanwhile, above ground, the BBC's Joshua Thorpe speaks to some disgruntled herdsmen.

(Picture: Mongolian herdsman; Credit: BBC)

The UK still doesn't know what kind of future trading relationship it wants with the EU, more than two years after voting to leave and with less than nine months left to go.

Ed Butler and BBC politics correspondent Rob Watson explore the difficult choices that London politicians still refuse to face up to. Audrey Tinline looks at one of the most vexing issues in the negotiations - the Irish border. And Ed speaks to Allie Renison of UK business lobby group, the Institute of Directors, about what kind of a deal her member companies would like to see.

(Picture: British Prime Minister Theresa May stands at an EU press conference podium; Credit: JP Black/LightRocket via Getty Images)

Germany is booming, yet some commentators suggest the nation's loss of confidence on the football pitch may mirror economic angst back home.

A shortage of skilled workers, inadequate public investment, a failure to grasp new technologies - these are just some of the criticisms that Germans level at their own economic performance. And at the heart of it is a political crisis over the influx of migrants - something many economists say is sorely needed in this ageing nation.

Anna-Katarina Noryskiewicz reports from Berlin, plus presenter Rob Young speaks to Gabriel Felbermayr, director of the Ifo Centre for International Economics in Germany.

(Picture: A German fan looks dejected following defeat in the 2018 World Cup; Credit: Kevin C. Cox/Getty Images)

Harley Davidson and Mid Continent Nail Corp are some of the US employers being hammered by America's escalating tariffs spat with its biggest trade partners.

Manuela Saragosa asks Vanessa, the author of The Girl On A Bike blog, what Harley fans like her make of the company's decision to move some motorcycle manufacturing from the US to Thailand in order to dodge new EU retaliatory tariffs. James Glassman of Mid Continent explains how the blow from the US President's steel import tariffs may flatten his company altogether in a county that voted 79% for Mr Trump. Plus former US trade advisor Pippa Malmgren explains why it may be wrong-headed for her government to try to address the country's perennial trade deficit in the first place.

(Picture: Hammer and nail; Credit: kutaytanir/Getty Images)

Millions of Syrians, including children as young as 10, are employed illegally in Turkish factories and shops - working long hours, underpaid and without insurance or legal rights. There is talk of an entire lost generation of child workers, missing out on school because their families need them to earn.

Ed Butler reports from Istanbul, where he meets a family of garment factory workers who say they are paid less than Turkish colleagues for their 10-12 hour days. He also meets some highly educated professionals, who have been reduced to taking on much lower skilled work since fleeing the civil war in their home country.

But does their plight evoke pity among their Turkish hosts? Or resentment that cheap Syrian labour is undercutting their own wages? And what can be done to improve lives, and get their kids out of work and back into school? Ed visits the Turkish charity Hayata Destek (Support to Life) to get some answers.

Producer: Laurence Knight

(Picture: A young Syrian refugee in Istanbul; Credit: Raddad Jebarah/NurPhoto via Getty Images)

Does the US President mix his business with his politics? And is this anything unusual in Washington DC?

Lisa Gilbert of Public Citizen, a non-profit watchdog in Washington DC, gives a summarised list of the alleged conflicts of interest of this administration, while Larry Sabato, director of the University of Virginia's Center for Politics, explains that contrary to popular expectation, almost none of the best performers among the first 44 US Presidents have been businessmen.

Plus Professor Martin Gilen of Princeton University tells Ed Butler that the evidence suggests that the influence of money over modern US politics has become as great as during the Gilded Age of robber barons of a century ago.

(Picture: Donald Trump at the Trump International Hotel In Washington DC; Credit: Chip Somodevilla/Getty Images)

Is kidnapping really that lucrative, and why are some countries, such as Mexico, plagued by the crime?

Ed Butler speaks to one kidnap victim from Mexico City, as well as Ioane Grillo, a journalist based there who has spent years studying the phenomenon. Kidnapping consultant Carlos Seoane explains what to do if you receive that dreaded phone call announcing that a loved one has been taken hostage. And Anja Shortland of Kings College London talks us through the logic behind kidnap insurance.

(Picture: A woman sits on a dirt road near Tijuana in Mexico after crashing her car while fleeing from would-be kidnappers; Credit: The Washington Post/ contributor/Getty Images)

If you have ever bought something in an online shop or been to a restaurant, chances are you’ve read a review for it, apparently written by a customer. And chances are you’ve also spotted more than a few suspicions ones, which stand out for their unqualified and lavish praise while being unusually free of personal details, or perhaps because they appear as a diatribe of awfulness designed to put you off forever. Who wrote those? In fact, there's a whole industry surrounding fake reviews - and it matters because more and more of us are buying things online and relying on other people's online advice to make the right choice. Freelance journalist Oobah Butler talks to us about his entire fake restaurant in London, James Kay, at review site Tripadvisor, tells us how they try to weed out inventions such as Oobah’s and brand reputation consultant Simon Wadsworth lays on tips for consumers and businesses.

(Picture: Customer review rating. Credit: Getty)

Would you invest in North Korea? US President Donald Trump raised the idea at his summit with North Korean leader Kim Jong-Un. His vision of a private condo on a North Korean beach is probably a long way away, but there are plenty of other countries lacking investment. Paul Domjan, global head of research at Exotix, an investment firm and research agency, explains what a frontier market is.

Byung-Yeon Kim, professor of economics at Seoul National University, tells us how North Korea’s economy works.

(Picture: A woman carries a boxed flat-screen television on her back as she crosses a road in Pyongyang. Credit: Getty Images.)