Waste – a Growing Global Health Threat

Health threats from waste thrive on socio-economic inequalities in two complementary ways: while affluence in parts of the global population produces mass consumption and rapid discarding of products (i.e. waste), poverty in another part invites the concentration and uncontrolled dumping of waste which amplifies its dangers to health...On a global scale, this transfer of waste from rich to poor unfolds when high-income countries export part of their hazardous waste to Africa and Asia

Waste – a Growing Global Health Threat


by Iris Borowy

Institute for the History, Theory and Ethics of Medicine, RWTH Aachen University, Germany


Many years ago I spent a summer vacation in a small village in Poland. The landscape was beautiful, the people were friendly, and I enjoyed taking my infant son out for walks. However, I soon realized one problem: there was no regular garbage removal, as there was in my native city in Germany, and I did not know where to leave my son’s diapers. Helplessly and with a very bad conscience I eventually left them on the garbage heap behind the house, where they may still be visible today, as my son is getting ready to finish his Master’s degree. For all I know, they may have begun to disintegrate and to leak their mixture of organic and chemical contents into the heap, its surrounding soil, flushed away by rains, the bits blown away by winds. It was a perfect manifestation of overlapping layers of how we deal with waste: the problem of health-hazardous organic waste solved by the creation of synthetic waste, whose disposal visibly created a – potentially health-hazardous – problem which I could not ignore as usual since, in the absence of regular removals to some official dump, it remained in sight. I cannot claim innocence in the clumsy ways in which humanity is trying to deal with its ever growing production of waste material.

Organic Waste

For most of human history, the primary form of waste was organic, mainly human and animal faeces. It was a major source of new health risks when groups of early humans became sedentary, replacing hunting and gathering with agriculture, and, on a global scale, it has remained a major health risk since. The scale of the problem is truly impressive. According to the WHO, 2.5 billion people do not have basic sanitation facilities, at least ten percent of the global population is estimated to consume food irrigated by wastewater and some 946 million people, 13% of the global population, are forced to defecate in the open. Poor sanitation, exposing people to human organic waste, is estimated to cause 280 000 diarrhoeal deaths per year and to contribute significantly to malnutrition, cholera, dysentery, hepatitis A, typhoid, polio and other diseases. Overall, unsafe sanitation is estimated to have caused over 800,000 deaths in 2013.

At the beginning of the twenty-first century, these numbers are upsetting. The only good news is that they are also improving. Expanding access to sanitation has been one of the Millennium Development Goals, and though the target to half, between 1990 and 2015, the proportion of the population without sustainable access to basic sanitation has been missed by almost 700 million people, progress has been substantial: between 1990 and 2015, the proportion of people with access to improved sanitation rose from 54% to 68%, corresponding to 2.1 billion people. According to the 2013 Global Burden of Disease Study, deaths due to unsafe sanitation had fallen by more than half since 1990. And efforts continue on a high scale. Also in 2013, a UN resolution calling for Sanitation for All was followed by a global campaign to end open defecation.

While these developments certainly do not justify complacency, they can give some reason for optimism. At the same time, health threats from other forms of waste, though not – yet – on quite the same level, are increasing alarming.

Household waste is one of them. Municipal solid waste is a broad category. It includes products such as food, paper, glass, bottles, can, metals, packaging and other forms of plastics, clothes, batteries, electronic appliances (e-waste), paints, chemicals, light bulbs, spray cans, fertilizer containers, pesticides or medical waste. Some of these items, such as paints, pesticides or batteries, are easily hazardous to health because they include material which is toxic when ingested. Other items, such as electronics or batteries, are normally harmless and only become dangerous to health when degraded through burning or physical destruction, as frequently happens after disposal.

Estimates vary, but the amount of municipal waste is significant by any measure. In the European Union, where efforts to reduce waste have had some effect, total waste production nevertheless remains high, amounting to 2.5 billion tonnes in 2010, about a third of which was recycled, the rest was landfilled or burned. In terms of household waste, every person in Europe is currently producing half a tonne of waste per year. Approximately 98 million tonnes are categorized as hazardous, and despite tight official control, management processes can involve the generation of problematic substances including methane, carbon dioxide and other potentially toxic gases (like carbon or sulphur oxides), metals (like lead, cadmium, mercury, chromium, arsenic and beryllium) and organic compounds (like PCBs), which, individually and collectively, may have adverse health effects. Suspected problems include cancers, respiratory symptoms, irritation of the skin, nose and eyes, gastrointestinal problems, fatigue, headaches, psychological problems and allergies. But despite some well-established cases, the overall picture is still very unclear. Emissions from waste management processes tend to be mixtures of many substances for which a toxicological knowledge is incomplete.

The situation is far more serious in municipalities of the global South. Here, a lot of discarded products get reintroduced into the material stream through repair, recycling, charity and buy-back schemes. However, in the absence of controlled waste management, the overall amount and the management processes are particularly problematic. Every year, cities around the world produce seven to ten billion tonnes of urban waste, and three billion people worldwide, i.e. 40% of the world population, have no access to controlled waste disposal facilities. Given population growth, increasing urbanization and growing per capita consumption, especially in Asia and Africa, the United Nations Environment Programme (UNEP) expects the amount of global household waste to double within the next fifteen years. At present, a lot of global solid waste ends up in open dumpsites: informal land disposal sites with no or extremely limited measures to protect the surrounding environment, specifically without liners, leachate or gas management systems and without anti-flooding measures. A Waste Atlas, issued by the University of Leeds and several environmental associations in 2014, portrays the fifty biggest dumpsites in the world. Of this group, 24 sites contain hazardous waste, seven include e-waste and all are huge. The “typical” dump has been in operation for seventeen years, covers 24 hectars, harbors 2.5 million tonnes of mixed wastes, affects over 800,000 people living within a range of ten kilometers and is the place of work for 1,300 informal recyclers, people picking valuables out of the waste without any protective gear. Health risks result particularly from persistent organic pollutants (POPs) and toxic elements such as lead, mercury, cadmium or arsenic, frequently released through open burning of plastics and other waste in order to recover scrap. These toxic chemicals are inhaled, ingested through contaminated food or water and absorbed through the skin. The most common health effects involve gastrointestinal, dermatological, respiratory, and genetic systems and several types of infectious diseases. Waste pickers but also residents in the vicinity are at elevated risk of suffering from diarrhoea, pneumonia, chronic bronchitis, asthma, headaches, chest pains, irritation of the skin, nose and eyes, typhoid, stomach ulcers and many forms of cancer. Living close to a dumpsite also increases risks of low birth weight, preterm delivery and congenital malformations. On the basis of Waste Atlas estimates, these fifty dumpsites alone would expose some forty million people to these elevated risks. A more conservative study places a “mere“ 3.5 million people at risk from industrial and municipal dumpsites. It nevertheless comes to disconcerting conclusions since it assumes that exposure to lead alone from industrial and municipal dumpsites results in 1.2 million DALYs (Disability Adjusted Life Years) per year.

In addition, landfills are the third most important source of anthropogenic methane emissions and thereby contribute to climate change, which, in view of its manifold direct and indirect effects on health through droughts, floods, changes in agricultural output, disease patterns etc. has been called the biggest global health threat of the 21st century. Thereby, dumpsites contribute to health burdens which are just beginning to be felt, whose overall extent is impossible to gauge with any degree of reliability at present but which are sure to be substantial in the not too distant future.

Medical Waste

Ironically, even activities designed to enhance health contribute to waste and related health hazards. Hospitals and other medical institutions discard copious amounts of materials. Estimates about the amount of waste produced by US hospitals range from 2.1 to 4.8 million tons per year, about 20 % of which is plastic, often contaminated, always difficult to degrade. In 1996, the Environmental Protection Agency identified hospitals as an important source of dioxins in the USA. On a worldwide scale, data are similar: about 80% of waste from healthcare institutions can be characterized as general waste, 20% is considered hazardous material, which may be infectious, toxic or radioactive. Problematic waste includes material contaminated with blood or other body fluids, body parts, syringes, needles, chemicals (notably mercury, solvents and disinfectants), pharmaceuticals like expired, unusued or contaminated drugs, vaccines and sera or radioactive waste.

Pharmaceuticals have proved to be both particularly difficult to control and to have particularly disconcerting potential long-term effects. Prescription drugs such as antibiotics, painkillers and antidepressants find their way into sewer systems and rivers from hospitals, industry or private homeowners, either when improperly disposed or as partially metabolized pharmaceuticals from human excreta. One of their most worrying characteristic is their potential to act as endocrine disruptors. This risk also emanates from other forms of waste, such as dioxins and dioxin-like compounds, polychlorinated biphenyls which are found in many everyday products– including plastics, metal food cans, detergents, flame retardants, food, toys, cosmetics, and pesticides. Inevitably, they end up as waste on dumpsites.

Endocrine disruptors are chemicals that adversely affect the endocrine system of living beings, including humans, by mimicking hormones, influencing developmental, reproductive, neurological, and immune processes in both humans and wildlife. They have an impact on the genetic program of the fetus during gestation, so that effects may only become visible many years later, during adolescence or adulthood of the evolving adult human being. There is also growing evidence that endocrine disruptors might play a role in the development of chronic diseases, including hormone-related cancers, obesity, diabetes and cardiovascular disease, all rising concerns of the global burden of disease. Long considered a frivolous concern of the wealthy rather than a serious global health problem, this view is changing as the long-term potential of the threat is emerging. A 2012 WHO/UNEP report commented that chemical exposure in pregnancy may well affect the health of several subsequent generations of people and wildlife that are not themselves exposed.

This possible continuation of health effects far into the future makes the true significance of some forms of waste difficult to assess. This is true for its contribution to the health threats created by endocrine disruptors and climate change. It is spectacularly even truer for radioactive waste.

Radioactive Waste

Radioactive waste derives predominantly from nuclear power plants and, to a lesser extent, from military activities, medical practices and research, all producing a constant stream of hazardous radioactive waste. Despite the self-confident claim of the International Atomic Energy Agency that the world has over half a century’s experience in managing radioactive waste – the characteristics of the waste are well known and therefore it can be safely managed, the extreme length of persisting radioactivity makes the risk virtually impossible to either calculate or control. As Harold Feiveson and colleagues from the Atomic Scientists commented with perfect understatement: The safeguarding of a geological spent fuel repository would have to be of indefinite duration, but the means to ensure continuity of the responsible institutions and knowledge on time scales exceeding thousands of years is unknown. By 2010, 225,000 tonnes of spent fuel were being stored on a temporary basis around the world, mostly at existing nuclear power reactor sites. Finding safe final disposal sites has proved a difficult process in all countries concerned because of almost ubiquitous resident protest. Repositories for low-level radioactive material exist in most countries that use nuclear energy. To date, there is no permanent repository in the world for high-level radioactive waste.

Acute exposure to high-level radioactivity can be lethal. Chronic exposure to radioactivity, even at low levels, can result in a number of health problems including cancers, cataracts and potentially harmful genetic changes. However, given the highly varied forms of radioactive waste and the relevant time frames ranging from tens of thousands to millions of years, i.e. many times the length of all known human history, any estimate about future health risks is beyond even the wildest speculation.

Common Themes

At first sight it may seem that there is little that connects this hodge-podge of health threats except the shared name of “waste.“ Is it really more than a clever choice of words to lump the lack of toilets in Bangladesh together with the lack of permanent repositories for high-tech nuclear energy technology in Germany? This paper argues that these varied forms are, indeed, linked by several intertwined points.

First, all forms of waste reflect the increasing burden human activities are placing on global ecologies through a combination a rising population numbers and rising per capita waste production. In the process, all forms of waste reflect a mixture of necessity and choice. All people eat, defecate, use some form of energy and require a certain number of products to organize their lives for survival and comfort. All people and societies have some degree of choice about how they make use of material they need and how they discard the leftovers that are no longer needed or wanted. Generally speaking, the amount of – inherently problematic – waste can be expressed in an adapted version of the I=PAT equation by Paul Ehrlich, Barry Commoner and John Holdren: Waste is a product of population size, affluence and technology: W = PAT. Rising numbers of people, growing wealth and inadequate technology all contribute to a growing burden of waste. Collectively, they test the limits of absorption capacities of local and global ecologies, the object of controversy since the 1972 publication of the Limits to Growth. All forms of waste, therefore, form part of a large framework of environmental health, ultimately reflecting how people around the world are arranging their lives as part of large and small ecological systems.

Secondly, all forms of waste represent some degree of health threat, ranging from cholera to cancer and miscarriages. In all cases, the risk has been recognized and measures have been taken to meet it. The standard form of health protection in high-income countries focuses on waste disposing at a safe distance from people to be protected. This approach follows the example of sanitation procedures in Europe and North America, which, in many ways, provided a precedent for subsequent decisions regarding waste management. In the course of the nineteenth century, flush toilets were introduced in most cities, which improved sanitation in the cities at the expense of increasing the pollution of rivers and areas downstream. This choice of strategy was a break with traditional methods in farming societies, and it was not uncontroversial since it deprived agriculture of valuable nutrients. Scientists like Justus von Liebig warned that the nationwide installation of water closets would result in the loss of material sufficient to feed millions of people. But by the early twentieth century water-borne sewage had been broadly accepted and it had become a sign of modernity and civilization that faeces and urin could be flushed away and forgotten. Similarly, effective waste management was understood as an organized municipal waste removal service and the responsible disposal of all sorts of waste, at a safe distance from residential areas. Flushing waste down rivers, burning it in incinerators, storing it in landfills or burying it deep in the soil followed a similar rationale of making waste disappear – from the world or at least from sight.

The underlying concept has been that of a linear form of human (economic) activity in which all products eventually end up having to be discarded and which entails the production of useless and potentially harmful material. This approach has been a successful component of a development which has improved health levels and increased life expectancy in many countries. But it comes with serious weaknesses. On the one hand, in the closed system of planet Earth matter is transformed but does not disappear, and as the combined effects of a growing world population and increased per capita consumption have led and are continuing to lead to unprecedented levels of waste, making it disappear is becoming increasingly problematic. At the same time, this form of disposal literally wastes valuable resources in a way that is less and less affordable as the exploitation of finite and often scarce raw materials is not keeping pace with growing demand by more and more affluent people. If you will, treating matter as “waste“ entails a process of creating waste as much as of getting rid of it.

The alternative entails treating “waste“ as valuable material and resources to be reintegrated into further production processes. In the form of recycling, this concept is hardly new, but both in the interest of health and of economic stability (which also clearly affects health!) present recycling processes will have to reach a whole new level.

The idea to perceived human production and activities as part of a larger circular form of economic processes and physical transformation is quite old. It is the natural outlook of agricultural societies in constant need of organic fertilizer, i.e. societies of the overwhelming part of human history. For some years, it has been re-invoked under various names. In the 1990s, the chemist Michael Braungart and the architect William McDonough developed the idea of a cradle-to-cradle principle of production, aiming at a form of production that mimics natural processes, in which the end products of one cycle become the resources for the next cycle of production. In 1994, Gunther Pauli followed the same approach when he created the Zero Emissions Research and Initiatives at the United Nations University. A few years later, the idea advanced from pet projects of individual researchers to policy guidelines of important international organizations. In 1999, the OECD picked up on these issues for its own new program on Environmentally Sound Management of Waste (ESM). A year later, it advocated a „zero-waste“ model. In 2014, the European Environment Agency argued that well-being in Europe depended on a resource-efficient, circular economy and the European Commission similarly called for a shift from a linear to a circular economy. It also funds programs designed to produce a fundamental change of perspective that entails finding innovative ways of using waste as a resource.

This approach has been endorsed in other context as well. Scientists and activists, including the World Toilet Organization, point out the waste of energy and nutrients involved in a “flush-and-forget” attitude. Consequently, a toilet model spread in India by social entrepreneur Bindeshwar Pathak not only offers crucial hygienic safety and privacy but also allows the waste to biodegrade into fertilizer. Even the proponents of nuclear energy at the IAEA are beginning to see recycling of radioactive waste as a possible management strategy, and if only to increase public acceptance. Evidently, the assumption is that a visible solution of the problem of radioactive waste would increase public acceptance of nuclear energy. Logically, the conclusion could be that nuclear energy – or any other economic activity – should only be accepted when a realistic, non-hazardous method of reintroducing end-products into economic processes has been found.

Few actors go as far as making this demand, but a growing number call for a fundamental shift in our economic system from linear to a circular structures. While sounding attractive and intuitively right on paper, implementation is far from simple for many reasons, including technical and political. It is also challenging in psychological terms, because traditionally, large part of circular economic systems have been driven by poverty. People automatically reuse, repair and recycle when they cannot afford to discard and buy new products, and in many ways “flush-and-forget” and the ability to replace instead of repair have been experienced as positive developments of growing wealth. In ways that have a direct bearing on health, the relation to waste has been a function of inequality and of poverty and wealth.

Generally speaking, wealthy communities have been able to organize waste disposal in ways the less privileged have not. This is true for organic as well as for municipal and industrial waste and on a local as well as on a global scale. Thus, in a survey of 39 cities around the world, 96% of upper middle-class and 100% of upper class residents used controlled disposal methods but only 35% of lower class people. As a global equivalent, according to the Waste Atlas all but two of the 50 largest dumpsites worldwide are located in Asia, Africa, Latin America and the Caribbean, the two outliers being in Alushta (Ukraine) and Belgrade (Serbia). Even within high-income countries, landfills and incinerators are usually located close to residential areas of socio-economically disadvantaged populations and minority groups. Not only is waste and its burden on human health unevenly distributed at its source, it often flows from rich to poor, disadvantaging the poor even further. On a local scale, sewage from wealthy areas in low-income countries is frequently discharged into storm drains, waterways or landfills and thereby contributes to the pollution of residential areas of the poor. Similarly, the waste from affluent areas, removed out of sight of their residents, routinely ends literally in the hands of the poor who are forced to work as waste pickers. Thus, in low-income areas waste recovery and recycling are driven by scarcity, high prices for materials and the availability of workers who are sufficiently poor and desperate to work on dumpsites.

On a global scale, this transfer of waste from rich to poor unfolds when high-income countries export part of their hazardous waste to Africa and Asia. This happens either illegally or in the name of recycling, which, in countries with widespread poverty and corruption, often means little more than disposal on open dumpsites, ready to poison the lives of people working on and near the place. Though the export of hazardous waste has officially been regulated and restricted by the Basel Convention (1989) and banned by the Bamako Convention (1991), such material regularly finds its way from Europe to Africa, especially with regard to discarded electronics such as mobile phones or outdated computer screens.

Overall, health threats from waste thrive on socio-economic inequalities in two complementary ways: while affluence in parts of the global population produces mass consumption and rapid discarding of products (i.e. waste), poverty in another part invites the concentration and uncontrolled dumping of waste which amplifies its dangers to health. At the same time, the possibility of disposal out of sight of where products are used and discarded allows the illusion of a quasi waste-free world, or at least a world in which waste is no problem. In simple terms: the affluent produce a lot of waste and, in addition to modern technology, it is the less privileged who are preventing them from having to face its consequences.

Would the Polish village have had a regular removal service if more residents had been wealthy, had produced larger amounts and more non-degradable forms of waste such as throw-away diapers? And would I have found a different solution if it had been my back yard?


Human activities have always produced some sort of waste, and frequently waste has come with health risks. This problem, therefore, is not new, but its scale is. Never before in human history have people produced so much that was not re-integrated into some type of production process again. And never before have people produced so much matter that presents a tangible health hazard for present as well as for future generations. It is a challenge of serious proportions which humanity has hardly begun facing. It is also a challenge that goes to the heart of the existing global developmental system: if socio-economic wellbeing, including health-related wellbeing, is based on a system that produces health hazards on a rising scale, this system is inefficient, at best, and potentially catastrophic at worst.

Addressing the problem will require shifting towards a circular form of economy and mitigating local and global inequality, two strategies which seem easy in theory but daunting in practice. Both will require fundamental social, economic and cultural changes, letting go off beliefs and perspectives to which we have become accustomed. One concerns the way we see the world, a shift that Kenneth Boulding described fifty years ago with his demand to shift from a cowboy to an astronaut economy, i.e. from a world with lots of empty space and ample resources to a world where a limited amount of material had to be continually reused. Another change pertains to definitions of “development,” where it is headed and how its levels serve to categorize different parts of the world. Clearly, when it comes to waste management, neither the policy of “developed” countries to produce a lot of waste, including forms with long-term risk potential, nor the policy of “developing” countries to leave uncontrolled management practices to indigent waste pickers who ruin their health in the process, can serve as useful models. Instead, development must aim at policies that combine low- (ideally no-) waste procedures with high-level health protection policies and that shrink global economic inequalities.