Waste generation is the secondary production of material considered not useful, in a production, use or consumption process. This is a concept fundamentally linked to human activity, since the waste produced by animals is part of biological cycles.
On the contrary, human waste, except strictly biological waste, is the product of the alteration of the natural cycles of matter. The transformation of matter and energy is the fundamental cause of waste generation.
This is because no production process is one hundred percent efficient and waste is always generated. On the other hand, the objects produced have a useful life, at the end of which they are transformed into waste from the process of use or consumption. Among the specific causes of waste generation are production processes, mass consumption of products, obsolescence and marketing advertising.
Some activities generate especially hazardous waste, such as mining, atomic energy production and medical activities. In turn, waste generation results in soil, water and air contamination and landscape deterioration. It can also cause disease and affect wildlife.
Avoiding the generation of garbage is almost impossible, but it is possible to reduce it to its minimum expression. For example, if industrial production processes become more efficient, less waste is produced.
On the other hand, rational consumption reduces the excessive use of resources and, therefore, the generation of waste. Finally, waste can be reused or converted into raw material through recycling.
Causes of Waste generation
-Population growth and economic growth
Considering that the main producer of waste is the human being, population growth is a determining factor in this problem. The human population grows exponentially and with it the demand for natural resources to meet various needs.
On the other hand, the production of goods to meet the growing demand and their consumption generates a high level of waste.
As the population increases, energy needs increase and more oil, coal or nuclear waste is produced. Likewise, a growing population requires more food, which implies a greater generation of agricultural, animal and fishing waste.
On the other hand, population growth combined with economic development also leads to the production of more cars, appliances, medicines, buildings and therefore more waste.
Economic growth is another factor that affects waste generation, because stronger economies have higher consumption. So, for example, the Organization for Economic Co-operation and Development (OECD) produces more than 40% of the world’s waste.
The OECD groups 36 countries that together generate almost 572 MT of solid waste per year. On the other hand, Latin America and the Caribbean generate around 150 million tons of solid waste per year.
-Consumerism, obsolescence and marketing
Consumption patterns are one of the main causes of waste generation. The economic system promotes exacerbated consumerism of all types of goods.
In this sense, the greater the consumption, the greater the generation of waste associated with strategies such as planned obsolescence and perceived obsolescence.
In planned obsolescence, products with a short shelf life are designed to increase their replacement in short cycles. On the other hand, perceived obsolescence encourages the consumer to substitute products that are still useful for new ones.
All these discarded products become waste from the process of consuming goods.
The textile, metallurgical, cement, chemical, plastic and oil refining industries produce the greatest amount of waste. In addition, these are among the most polluting that exist.
Small and medium companies
There are small industries or companies that produce waste services that, in some cases, can be dangerous. For example, a metal factory may have hazardous waste associated with cleaning and processing its products.
On the other hand, a small self-service store, hardware store, small copy shop, or even a general merchandise store may generate small amounts of hazardous waste.
Among them are fuels and oils, lacquers and paints, containing heavy metals, organic solvents and other toxic substances.
-Mining and oil
Mineral and oil extraction processes generate a large amount of toxic waste.
One of the most extreme cases is the extraction of gold in open pit mines, because highly toxic substances are used. Waste substances such as mercury, arsenic and cyanide end up contaminating soil and water.
Oil extraction processes generate so-called drilling muds as waste, which contain large amounts of heavy metals. In the case of the hydraulic rock fracturing technique or fracturing , additives are used that are transformed into process residues.
These additives include polyacrylamide (carcinogenic), ethylene glycol (affects the nervous system and causes metabolic problems), and glutaraldehyde (dermatitis and respiratory allergies).
Radioactive waste is among the most dangerous, especially fuel waste from highly active nuclear power plants. Similarly, radioactive waste is generated in industrial, agricultural and medical areas, although its radioactive activity is medium to low.
-Agriculture, livestock and fish farming
In intensive agriculture, a large number of inputs are used, including fertilizers and biocides. Many of these inputs become waste from the agricultural process and end up polluting the environment.
On the other hand, being a highly mechanized agriculture consumes a high volume of fuels and lubricants. These compounds produce waste that can cause spills or generate greenhouse gases due to their combustion.
Livestock and fish farming
In southern Chile, for example, salmon farming and the fish processing industry are a source of polluting waste. The main residues generated are organic, in addition to antibiotics used in fish farming.
Cities, especially overcrowded ones, are the biggest centers of waste generation. Almost 50% of waste worldwide is organic and the majority is generated from marketing and consumption processes in cities.
New York City, with almost 20 million inhabitants, produces about 33 million tons per year. In Latin America, Mexico City (21 million inhabitants) is the second in the world, with 12 million tons per year.
Another major source of polluting waste in cities is sewage that is not properly treated. In fact, all rivers close to large cities have some degree of contamination from this cause.
-Construction and demolition
The construction and demolition of works generates solid waste mainly in the form of debris. This debris can be highly polluting as it includes traces of paints, resins, metals and other components.
-Health services, research laboratories and pharmaceuticals
Hospitals and health services produce waste in many cases at high risk to public health. Such waste includes human remains (blood, tissue), bacterial cultures, chemicals and radioactive material.
Likewise, research laboratories in the biological area and with pharmaceutical laboratories generate a large amount of waste. For example, a study carried out in Spain shows the discharge of up to 3 tons per year of 30 medicines in the Ebro River.
Consequences of Waste generation
Soil, water and air pollution
Much of the waste generated and handled ends up in the soil, groundwater and on the surface or in the atmosphere. Cities generate garbage and effluents that pollute the environment with heavy metals, organic matter and other residues.
Industries produce gases that pollute soil, water and air through acid rain.
The accumulation of solid waste and untreated effluents deteriorates the landscape, affecting recreational and tourist activities. The accumulation of garbage, odors and the proliferation of undesirable animals reduces the attractiveness of the leisure areas.
Organic waste can carry disease-causing organisms. Some cases, such as hospital waste, are especially dangerous.
Untreated effluents from cities transmit infectious and contagious diseases such as cholera, enteritis and amoebiasis, among others. Heavy metals absorbed by plants and dissolved in water pollute those who consume them.
Polluted air in big cities due to vehicle traffic and industries causes respiratory problems and dermatitis.
Deterioration of wildlife
Most human-generated waste, when it enters ecosystems, alters its balance and affects wildlife. For example, waste from drilling oil wells or oil spills is deadly for aquatic and terrestrial fauna.
Likewise, acid rain affects forests and aquatic organisms, and agricultural waste causes the death of animals and plants.
How to avoid waste generation
Recycling in Buenos Aires, Argentina. Source: Gelpgim22 (Sergio Panei Pitrau) [CC BY 3.0 (https://creativecommons.org/licenses/by/3.0)]
Every material transformation process generates waste, but it is possible to minimize it, making production processes more efficient. In this sense, comprehensive waste management seeks to minimize its generation through prevention or reduction, reuse and recycling.
Efficiency and production quality
Using systems engineering principles, production processes become more efficient and waste is reduced.
For this, it is important that the largest proportion of raw materials is part of the finished products. In this sense, it is necessary to redesign the production chain or to incorporate machines with greater precision and efficiency.
Likewise, it is convenient to improve the quality and durability of machinery and equipment vehicles. In this way, it is possible that these products take longer to transform into products.
Rational consumption and marketing
Another way to prevent waste generation is rational consumption, since a conscious consumer will restrict his demand for resources. Furthermore, if demand is directed towards recycled or less polluting products, waste production will be reduced.
For example, you can promote the consumption of products with biodegradable packaging or products that are more durable and repairable.
These are products that can be used again for the original or for a different purpose. In this sense, when designing a product, its subsequent reuse must be planned, as is the case with glass bottles.
Other examples are the use of tires to build swings or guardrails or plastic bottles to build the roof of a farmhouse. Likewise, discarded objects can be reused to create works of art in the field of modern sculpture.
Unlike reuse, recycling refers to the reuse of materials that make up a discarded object, not the object itself. In this sense, a large amount of solid waste can be recycled to take advantage of the raw materials that compose it.
An example of this is the recovery of metals and other components of electronic devices or the recycling of paper and cardboard.
Objects made of biodegradable material
Biodegradation is the decomposition of a material by the action of living organisms, mainly bacteria and fungi. Thus, products with biodegradable plastics can be designed.
In this way, the waste generated will disappear in the short term, without producing negative effects on the environment.
Waste generation in Mexico
Mexico ranks first in Latin America in the generation of solid waste, especially urban waste. It is estimated that more than 86,000 tons of garbage are produced daily across the country, of which 13,000 originate in Mexico City.
On the other hand, construction and demolition generate a large amount of waste, estimating that in 2001 7 million tons/year were produced.
Gaseous waste: greenhouse gases
This country is the main emitter of greenhouse gases in the region. According to the National Inventory of Emissions of Greenhouse Gases and Compounds (INEGYCEI), Mexico emitted 683 million tons of carbon dioxide.
Liquid waste: untreated wastewater and runoff
In Mexico, industries produce more than 5 km3 of wastewater per year and urban centers around 7 km3 of wastewater per year. Due to poor treatment, these effluents carry polluting waste.
Among these pollutants are organic matter, nutrients (nitrogen and phosphorus), microorganisms (fecal coliforms), heavy metals and hydrocarbon derivatives. The industries that produce the most liquid waste in Mexico are sugar, chemicals and oil.
Waste generation in Colombia
Colombia generates around 11.6 million tons of solid waste per year, of which only 17% is recycled. According to the Inter-American Development Bank (IDB) for 2015, more than 60% of solid waste produced was organic, followed by plastic.
Regarding hospital waste, the city of Bogotá generated more than 350 tons in 2015. On the other hand, it is estimated that more than 600,000 tons of construction and demolition waste are generated annually in the city of Medellín.
Gaseous waste: greenhouse gases
Between 1990 and 2014, Colombia increased greenhouse gas emissions by 10%. The biggest contributions come from deforestation and agricultural activities followed by mining.
Liquid waste: untreated wastewater and runoff
The agricultural, industrial and domestic sectors together produce about 9,000 tons of organic matter waste through sewage. Among the contributions of industrial waste, the 85 tons of beer that were dumped into waterways in 1985 stand out.
Likewise, hazardous waste is produced, such as volatile organic compounds, halogenated solvents and heavy metals. Among the industries that contribute the most liquid waste waste to the environment are petroleum refining, chemicals and tanneries.