I welcome your editorial and related coverage (Stop the spread of the tobacco companies’ poison, 13 July). Tobacco smoking is still the largest single preventable cause of ill-health and death. In the UK the reduction in smoking is one of the great public health success stories. However, it is important that this achievement is not reversed. E-cigarettes should be monitored closely.

Tobacco companies have tremendous financial and political power and, despite the overwhelming medical evidence against cigarettes, they are still able to sell their products. Moreover, certain markets are expanding. Two of the world’s largest tobacco companies are based in the UK. Both continue to perform strongly and are confident about their future performances, especially as markets are growing in lower income countries where there is tremendous potential for profit.

Many of the current strategies used by tobacco companies are not new. More than 30 years ago, Peter Taylor published a seminal book which provided a comprehensive insight into the world of public health politics. The Smoke Ring discusses the ring of political and economic interests surrounding the tobacco industry.

Dr Michael Craig Watson

University of Nottingham

• We are concerned, if not surprised, to read the Guardian’s exposé of big tobacco’s use of trade measures to threaten African countries into watering down their efforts to promote public health (Report, 12 July).

A major problem with trade and investment agreements is their chilling effect on public interest legislation: countries that lack the time or resources to defend themselves against a trade dispute hold back from introducing new measures that are good for the public but threaten corporate profits and could provoke a trade challenge. This is particularly problematic where corporations are able to use the investor-state dispute settlement mechanism to sue governments in private tribunals where corporate lawyers act as judges.

For example, after Philip Morris challenged Uruguay and Australia for introducing graphic warnings on cigarette packaging and plain packaging respectively, Costa Rica, Paraguay and New Zealand delayed introducing similar measures. Philip Morris lost that case, but big tobacco is still attempting to bully (particularly low and middle income) countries that attempt to put the health of their citizens before shareholder profit. This has to be stopped.

Countries must be free to pursue independent development and public health strategies. That means having the space to regulate and tax in the public interest without the threat of litigation. We would like to see trade agreements that encourage governments to promote public health objectives, rather than acting as a brake on progress. This requires a fundamental shift in the way that we approach trade deals in the future.

Matthew Bramall Health Poverty Action

Paul Keenlyside Trade Justice Movement

David McCoy Professor of Global Public Health, Queen Mary University London

Dr Penelope Milsom Medact

Deowan Mohee African Tobacco Control Alliance

Alvin Mosioma Tax Justice Network – Africa

Mary Assunta South East Asia Tobacco Control Alliance

Deborah Arnott ASH (UK)

Laurent Huber Action on Smoking and Health (US)

Chiara Bodini and David Sanders People’s Health Movement

Andreas Wulf Medico International

Jean Blaylock Global Justice Now

Mark Dearn War on Want

Tabitha Ha STOPAIDS

Thanguy Nzue Obame People’s Health Movement Gabon

• That big tobacco hinders the adoption of anti-smoking legislation is no surprise. Your leader correctly identifies the best route to behavioural change – shareholder pressure – but does not highlight the key channel to achieve this. Big tobacco needs to diversify. This is where shareholder pressure should be applied: to encourage manufacturers and associated leaf merchants to invest in non-harmful products and speed up the process of product diversification. In addition, governments in the south and their development partners should work with manufacturers and merchants to reduce big tobacco’s own addiction to the evil weed.

Dr Martin Prowse

Lund University, Sweden

• It is a proud claim we make in this country that 0.7% of our GDP is committed to international development. But efforts to reduce poverty and ill health in developing countries are seriously undermined by the activities of companies such as British American Tobacco.

The tobacco industry has an unrivalled record for dishonesty in trying to prevent its customers becoming aware that there is a 50% chance that they will die from smoking-related causes. It has been a long battle in this country to establish strong measures of tobacco control which have significantly reduced the prevalence of smoking.

In response, the tobacco companies are seeking to get many more people in the developing world addicted to their products. They use the same bogus arguments that have been defeated in the UK to prevent attempts by governments in those countries to prevent this happening. They behave in this way because they make great profits.

The world would be a much better place if such dangerous products were banned. But if this cannot be done by international agreement, then we must at least ensure that we tax them in such a way as to deter such behaviour. The funds raised could also help poorer countries in their fight to establish similar measures of tobacco control to those that are working in the UK.

Chris Rennard

Liberal Democrat, House of Lords

• It is deeply unethical that BAT has taken African countries to court to dilute their efforts to protect their populations’ health from tobacco. These countries are still fighting infectious diseases and face a double burden of poor health as a result of non-communicable diseases, with very limited budgets to deal with these.

According to the international covenant on economic, social and cultural rights in the context of business activities (June 2017), these countries are obliged to protect their public’s health, and this includes regulating to restrict marketing and advertising of harmful products such as tobacco.

BAT is headquartered in the UK, so the UK is required to take the necessary steps to prevent human rights violations abroad and it is “contradictory to remain passive where the conduct of an entity may lead to foreseeable harm”.

Moreover, “extraterritorial obligation to protect requires the UK to take steps to prevent and redress infringements of rights that occur outside their territories due to the activities of business entities over which they can exercise control.”

If the UK does not fulfil its extraterritorial responsibility to protect future smokers in Africa, it is possible that it could be liable for damages when many develop cancer, heart disease and strokes. It is incoherent to give British aid for healthcare to these countries while at the same time a UK company is promoting harmful products that diminish people’s right to health.

On a related subject, British MP pension fund, the Parliamentary Contributory Pension Fund (PCPF), invests in BAT and some UK local authority pensions invest large sums in the tobacco industry which many already consider unethical even before the article in the Guardian.

Dr Bernadette O’Hare

University of Malawi and University of St Andrews

• Smoking remains a major public health concern, a major contributor to overall mortality and morbidity, to air and water pollution and to physical, economic, social and psychological trauma. However, I must take issue with your allusion to the size of the distance from the developed to the developing world.

The Grenfell tragedy has shone a light on the ills of western societies where people are denied their fundamental rights to safe, clean and adequate housing; where hundreds of thousands are languishing in cramped and dangerous buildings; where homelessness, labour exploitation, knife crimes, racial and religious intolerance and joblessness are increasingly becoming hallmarks of society – and where cover up and deceit are becoming the norm rather than the exception.

To be fair, many developing countries have already recovered from the ills that still plague the developed world. Take a look in the mirror.

Dr Munjed Farid Al Qutob

London

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