Households are burning plastic waste as fuel for cooking and heating in slums the world over

Poor people in vast city slums across the Global South are burning plastic to cook their food, warm their homes and boil water for hot showers.

Waste plastic is plentiful and highly flammable. So it’s not surprising people in developing countries, mainly in Africa, Asia and Latin America, are putting it to use – especially as wood is increasingly scarce.

But burning plastic is hazardous, as it releases toxins into the surrounding air – and possibly into the food on the stove.

We wanted to draw attention to this growing problem, which has received little attention to date despite the many potential harms.

In our new “perspective” paper, published in Nature Cities, we explain why so many communities are using plastic as an energy source.

We then explore further research needed and recommend ways for policymakers to tackle the issue.

Mountains of plastic waste

The world has produced more plastic in the past 20 years than the total previously produced since commercial production began in 1950. Roughly half a billion tonnes of plastic is now produced every year.

Plastic production is still accelerating. Global plastic use is predicted to almost triple by 2060 due to soaring demand from a growing population with rising incomes.

Unfortunately, most plastic is not recycled. Instead, it is discarded and ultimately ends up polluting marginal land such as flooded areas and open dumping grounds before making its way into the ocean.

A product of energy poverty in city slums

Increasing urbanisation is reducing access to traditional fuels such as wood and crop residue from farmland.

But plastic is readily available. Low-income households with little or no access to gas or electricity often find themselves living alongside mountains of rubbish.

This plastic, made from fossil fuels, represents a cheap and convenient fuel. It’s lightweight, easy to transport, and a nuisance material that people want to be rid of. Plastic is also relatively easy to dry and store, but can burn even when wet. It’s also flexible and pliable, so it can be used easily in traditional cooking arrangements such as basic stoves.

Burning plastic releases toxins such as dioxins, furans and heavy metals into the air. These chemicals are known to cause cancer, heart disease and lung diseases.

The more vulnerable people in the household – including women and children and those who spend more time indoors – tend to be most exposed to the fumes. But the problem also affects people in the neighbourhood and the wider community.

Burning plastic is likely to also contaminate food. For example, eggs from farms near plastic waste incinerators in Indonesia contained hazardous chemicals from burned plastic. However, more evidence is needed around food contamination.

Furthermore, when households burn plastic bottles and other containers, some of the original contents also burn. Given chemicals are poorly regulated, the consequences of burning plastic could be greater still.

Overcoming the problem

A first step to overcoming the problem is understanding the reality of those living in slums. Policy-makers need to recognise these people’s needs and the challenges they face.

Extensive research is needed to design the most effective and inclusive policy interventions. This needs to be addressed if we are to reduce the associated health and environmental impacts on such large populations across the world.

We have gathered a collaborative, multidisciplinary team of researchers from around 35 countries – mostly in the Global South – to better understand the problem. We recently completed a survey of people exposed to the issue such as local government employees, teachers and community workers in more than 100 cities in 26 countries.

We are also examining the emissions from waste plastic during food preparation to determine the extent of contamination in variety of stoves.

Nobody wants to burn plastic waste to cook food, so policies like ban on burning plastic with out contextual intervention will not work. There is a need to design inclusive policy interventions that provide equitable benefits to the wider community. For example, encouraging people to:

• wash any plastic before it is burned, to remove chemical residues
• use improved cookstoves that vent the fumes outside
• expand basic urban amenities like waste management to low income settlements
• provide support to help lift households out of poverty.

Each approach will depend on the specific requirements of the slum settlement. But by implementing multiple approaches in parallel, we can tackle the problem more effectively.