British American Tobacco and Imperial Brands profited from child labour, exploitation and dangerous conditions on tobacco farms in Malawi, according to a legal claim launched after a Guardian investigation. The British firms, which reported combined earnings of £12.5bn last year, should compensate 7,020 children and adults who work in their supply chain, according to documents filed at the high court by the law firm Leigh Day. The claim alleges “widespread use of unlawful child labour, unlawful forced labour and the systematic exposure of vulnerable and impoverished adults and children to extremely hazardous working conditions with minimal protection against industrial accidents, injuries and diseases”. Leigh Day said the tobacco industry was structured to give the multinational cigarette companies the appearance of separation from working conditions in the tobacco fields. Firms such as BAT and Imperial typically buy the leaves via third-party dealers, who in turn source them from contract farmers. But the two companies were aware of the conditions faced by farmers in Malawi, including children, according to the claim, and had previously indicated they exert a high degree of control over conditions in their supply chains. The claim was triggered by a 2018 Guardian investigation, which found that tobacco farmers were exposed to nicotine poisoning, toxic pesticides and harsh weather conditions during labour-intensive shifts in areas where up to 63% of children were engaged in child labour. The leaves harvested on those Malawian farms end up in cigarettes around the world, including the US, which last year suspended imports from the southern African country over child labour allegations. Beneficiaries of BAT and Imperial’s profits include UK local authority retirement schemes, which held £1.7bn of tobacco investments on behalf of healthcare providers and schools as of 2018, according to Guardian analysis. BAT makes brands including Benson & Hedges and Lucky Strike. A spokesperson for the company said: “BAT takes human rights very seriously and expects all employees and suppliers to respect and uphold them. “It would not be appropriate for us to comment on the specifics of this situation, given the possibility of future litigation.” The company said it set strict standards for itself and its suppliers, adding: “We take the issue of child labour extremely seriously and strongly agree that children must never be exploited, exposed to danger or denied an education.” Imperial, which makes Gauloises, Lambert & Butler and Golden Virginia rolling tobacco, said: “We take the issue of child and forced labour very seriously and do not condone exploitative practices in our supply chains, as made clear in our code of conduct which is published on our corporate website. “We actively seek to prevent exploitation through multi-stakeholder initiatives, including an industry-wide sustainable tobacco programme which is aligned to the UN guiding principles. We will defend any claim vigorously and it would be inappropriate to comment further.” Leigh Day is expected to file more details of its claim in January before setting the monetary value at a later date. The case could have significant implications for companies with supply chains in parts of the world where poor working conditions and child labour are common.