By Ed Upright

LONDON, June 16 (Thomson Reuters Foundation) - British supermarkets scrambled to remove certain brands of corned beef from their shelves this month after it was found that they might be tainted by links to slave labour in Brazil.

Yet several other everyday items also have dubious associations - including an increased risk of links to slavery - according to new research by a data intelligence company.

A wide range of products, from pet food to toys, have previously been implicated in modern slavery through their complex global supply chains.

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The illegal industry traps an estimated 46 million people globally, according to the 2016 Global Slavery Index, and produces profits of about $150 billion a year, according to the International Labour Organization.

Risk analysis firm Polecat analysed about 30 million social media posts and over 300,000 online sources daily, over the course of 90 days.

In research released on Friday, it found tea, coffee, coal, sugar and tobacco are among the top eight products that have an increased risk of slavery links.

The analysis also references particular geographical hotspots, where the risk of slavery is higher.

Topping the charts in social media was coal from North Korea, with 300 indications of risk-based language in the last 90 days, according to Polecat.

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The U.S. State Department's 2016 Trafficking in Persons report found that North Korea has an estimated 80,000 to 120,000 prisoners in remote political camps where all inmates, including children, are subject to forced labour, including mining.

Next came gold from Tanzania, a country with more than 4 million child labourers, according to a government survey released last year with the International Labour Organization.

Third was cotton in Uzbekistan, the world's fifth-largest cotton exporter but a position that rights campaigners say is maintained by a state-orchestrated forced labour system.

In online articles, blogs and features, Polecat found that gravel in the United States was at the highest risk of slavery links, with 42 examples of risk-based language found.

Earlier this year, local media in the U.S state of Tennessee reported a Guatemalan man and a pair of his ex-colleagues filed a lawsuit against a landscaping firm, accusing the company of trafficking and forced labour.

This was followed by cotton in Uzbekistan and tobacco in the United States.

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Polecat co-founder Bronwyn Kunhardt told the Thomson Reuters Foundation the task of monitoring global supply chains for modern slavery is extremely complex and requires new approaches.

"Interrogating social media and unstructured data plays a crucial role in identifying potential threats and red flags in real time," said Kunhardt.

"Few companies are doing this comprehensively today, so it seems unlikely that we've seen the last big scandal related to slavery and bad practices in the supply chain."

(Reporting by Ed Upright, Editing by Ros Russell.; Please credit Thomson Reuters Foundation, the charitable arm of Thomson Reuters, that covers humanitarian news, women's rights, trafficking and climate change. Visit news.trust.org)