Incineration: Garbage Solution Or Air Pollutant?

Incineration is a waste treatment technology that involves burning commercial, residential, and hazardous waste. While it is often touted as a solution to the world's growing waste problem, the question of whether incinerating garbage pollutes the air is a complex one. On the one hand, incineration releases harmful chemicals and pollutants into the air, including particulate matter, heavy metals, and toxic chemicals, which can have serious public health impacts. On the other hand, some argue that incineration is still better than the alternative of landfills, which produce methane and air pollutants. The impact of incineration also depends on the specific circumstances, such as the business practices and the country's environmental benchmarks.

Incineration's impact on recycling rates

Incineration is the burning of refuse in incinerators to generate electricity, also known as "Energy from Waste". It has been promoted as a way to reduce carbon emissions from waste treatment and as an alternative to landfilling, especially for plastic waste. However, the idea that incineration is environmentally beneficial has been challenged.

The construction of incinerators has increased in many countries, including the UK, where local authorities have ramped up their construction. This is due to the perception of incineration as a solution to the problem of increasing waste, particularly in the context of China's decision to stop accepting foreign waste. However, this focus on incineration may have a negative impact on recycling rates.

A report by Eunomia Research and Consulting, commissioned by the environmental law charity ClientEarth, found a direct correlation between regions with waste incineration contracts and low recycling rates. In England, more waste is now burned than recycled, with 11.6 million tonnes incinerated in 2019 compared to 10.9 million tonnes recycled. This trend is not limited to the UK; recycling rates have stagnated in many countries since around 2005, and the increase in incineration may be a contributing factor.

The availability of incineration as a waste management option may reduce the incentive to recycle. This "feed the beast" mentality associated with efficient incineration could make recycling certain materials seem obsolete. For example, the Dispatches programme found that around 60% of the waste going to incinerators in England could have been recycled instead. Additionally, the construction of new incinerators requires significant quantities of waste to operate, further disincentivizing waste reduction and recycling.

To address the potential negative impact of incineration on recycling rates, economic instruments such as incineration taxes can be implemented to provide incentives for the waste hierarchy, which prioritises reduce, reuse, and recycle. Measures should also be taken to ensure that waste collected for recycling is not incinerated and to increase the share of reusable packaging.

Air pollution and health risks

Incinerating garbage releases harmful chemicals and pollutants, which enter the air, water, and food supply near incinerators. These include air pollutants such as particulate matter, which can exacerbate respiratory issues and cause lung and heart disease. Nitrogen oxides (NOx) and sulphur dioxide (SO2) are also released during incineration, contributing to poor air quality and subsequent health issues.

The incineration process also emits heavy metals such as lead and mercury, which are associated with neurological diseases. Furthermore, toxic chemicals such as PFAS and dioxins are released, increasing the risk of cancer and other health problems. These toxins can persist in the environment, move across the globe, and accumulate in the food chain, causing long-term harm to both wildlife and human health.

The impact of incinerator emissions on human health is significant, with studies indicating that proximity to waste incineration facilities may increase the risks of cancers, birth defects, and other adverse health outcomes. Low-income communities and communities of color are disproportionately affected by these toxic emissions, as incinerators are often located in socio-economically disadvantaged areas.

The promotion of incineration as a "green" or environmentally friendly solution by industries has been criticized as greenwashing. In reality, incineration contributes to global warming through the release of carbon dioxide (CO2) and other greenhouse gases, and it also affects recycling rates, as it relies on significant waste volumes to operate. Therefore, incineration is not a sustainable solution and can disincentivize waste reduction and recycling efforts, ultimately impacting the environment and human health.

Energy generation and carbon intensity

The process of incineration involves burning waste to produce electricity. While this method of energy generation has been promoted as a low-carbon alternative to landfilling, evidence suggests that incineration is a significant contributor to carbon emissions and air pollution.

The carbon intensity of incinerators in Europe is approximately 540 gr CO2/kWh, which is nearly double the concentration of CO2 emissions from the average EU electricity grid (296 gr CO2/kWh). Furthermore, incineration produces more greenhouse gas emissions per unit of electricity generated than any other power source. From 2006 to 2016, the amount of waste incinerated in Europe increased by 30%, leading to a doubling of CO2 emissions from incinerators. In 2017, Waste-to-Energy (WTE) incinerators in the EU released over 40 Mt of fossil CO2 into the atmosphere.

The high carbon intensity of incineration is due to the burning of hard-to-recycle plastic waste. Plastic is derived from crude oil, and when burned, it releases carbon. As the proportion of plastic waste sent to incinerators increases, so does the carbon impact of the incineration process. This trend is particularly concerning given the growing global plastic waste problem.

In addition to carbon emissions, incineration releases various harmful pollutants into the air, including particulate matter, heavy metals such as lead and mercury, and toxic chemicals like PFAS and dioxins. These pollutants have been linked to lung and heart diseases, neurological issues, and cancer. Incinerators are often located in deprived areas and communities of colour, exacerbating health risks for vulnerable populations.

Compared to recycling and composting, incineration requires more energy and results in higher greenhouse gas emissions. Recycling saves more energy and avoids greenhouse gas emissions by reducing the need to create new products from virgin materials. Composting organic materials improves soil health and reduces the need for chemically derived fertilizers, further reducing environmental impacts.

Ash and sludge disposal

Incineration is a waste management method that involves burning waste at extremely high temperatures, often exceeding 850°C. While it is touted by some as an "easy" and "green" alternative to other waste management methods, it is a major source of toxic air pollution and releases harmful chemicals and pollutants, including particulate matter, heavy metals, and toxic chemicals. These emissions negatively impact local air quality and have been linked to various health issues, such as lung and heart diseases, neurological problems, and cancer.

The ash and sludge produced during the incineration process can be disposed of or reused in various ways. One option is to dispose of the ash and sludge in landfills or other designated disposal sites. This method ensures that the waste is contained and does not directly release toxins into the environment. However, it is important to note that landfills can still contribute to environmental concerns, such as soil and water contamination, if not properly designed and managed.

Another option for ash and sludge disposal is to utilize them in the construction industry. The residue ash from incinerated sewage sludge, known as sewage sludge ash (SSA), can be reused as an adsorbent material or incorporated into building materials. This approach not only reduces the amount of waste that needs to be disposed of but also provides a valuable resource for the construction industry. The European Commission's Circular Economy Action Plan, adopted in March 2020, promotes the reuse of SSA to support sustainable growth and reduce the environmental impact of waste management.

In addition to disposal and reuse options, it is crucial to consider the potential risks associated with ash and sludge disposal. The composition of the ash and sludge depends on the type of waste incinerated, and they may contain harmful substances such as heavy metals and toxic chemicals. Therefore, proper handling and disposal methods are essential to prevent further environmental contamination. Incinerator facilities should have protocols in place to ensure the safe collection, transportation, and disposal of ash and sludge to minimize any potential risks to human health and the environment.

While incineration can reduce the volume and mass of waste, it is important to prioritize waste reduction and recycling to minimize the negative impacts of waste management on the environment and public health. Recycling, composting, and adopting reusable packaging can help reduce the amount of waste sent for incineration, thereby decreasing the emission of toxins and pollutants. Additionally, implementing economic instruments, such as incineration taxes, can provide incentives for waste hierarchy and promote recycling and reuse over incineration.

Environmental inequalities

Incinerating garbage releases harmful chemicals and pollutants into the air, worsening environmental inequalities. These toxins include ultra-fine particles, dioxins, heavy metals, and persistent organic pollutants, which contribute to toxic air pollution and have severe health impacts. The emissions from incinerators affect nearby communities, with low-income communities, communities of colour, and Indigenous Peoples' communities bearing the brunt of these toxic burdens.

The concentration of incinerators in these vulnerable communities leads to cumulative impacts from multiple pollution sources, exacerbating existing environmental injustices. The emissions from incinerators contain harmful pollutants, such as particulate matter, heavy metals, and toxic chemicals, which can cause lung and heart diseases, birth defects, and increased risks of cancers. The health impacts of incinerator emissions disproportionately affect communities that already face socioeconomic challenges and have limited access to healthcare and environmental resources.

Additionally, incinerators create financial risks for host communities. The volatile revenue model, high operation and maintenance costs, and the need for expensive upgrades to pollution control equipment can burden communities with increased taxes or public financing through bonds. As plants age, their environmental performance may degrade, further endangering the health and well-being of nearby residents.

Furthermore, incinerators reduce incentives to adopt more sustainable waste practices. Zero-waste practices, such as recycling, composting, and reducing waste generation, offer environmentally superior alternatives to incineration. These practices conserve energy, minimise pollution, and divert waste from landfills and incinerators. However, the presence of incinerators can discourage investment in and implementation of these sustainable waste management strategies.

To address environmental inequalities and promote environmental justice, it is crucial to transition towards a circular and sustainable economy. This involves prioritising waste reduction, recycling, and composting over waste incineration. By implementing effective waste management strategies, such as those advocated by environmental and environmental justice groups, communities can minimise the negative impacts of incineration on their health, environment, and economic well-being.

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