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According to the General Law for Prevention and Integral Management of Waste, special waste is any production-generated residual material that is not considered municipal solid waste or hazardous waste or comes from large municipal solid waste generators. The law also defines the different types of special waste. Another consultation tool is the Official Mexican Standard NOM-161-SEMARNAT-2011, which establishes the criteria for classifying special waste, determining which are subject to a management plan, listing wastes, including or excluding special waste from lists, and developing management plans.

As reported by the Ministry of Environment and Natural Resources in its 2012 Basic Diagnosis on Waste Management, 84 million metric tons of 14 types of special waste are generated in Mexico each year. Additionally, 805 thousand vehicles are disposed of every year and these numbers are still on the rise.

Electronic Waste

Electrical and electronic devices work using electricity and electromagnetic fields. At the end of their useful life, these devices are discarded and become electronic waste. When handled improperly, electronic waste can cause substantial harm to human health and the environment due to the substances it contains (lead, cadmium, mercury, chromium, or persistent organic pollutants). Electronic waste also contains valuable metals such as palladium, gold, silver, copper, ruthenium, or indium that can be reused as raw materials for new products. Other hazardous substances found in electronic waste are halogenated flame retardants (polybrominated biphenyls, polychlorinated biphenyls, or polybrominated diphenyl ethers), which were added to the Stockholm Convention.

Moreover, beryllium, antimony, rare earth elements, ozone-depleting substances, and greenhouse gases can be present in electronic waste. Nevertheless, these pollutants are found only in refrigerators, air conditioners, and other devices containing chlorofluorocarbons and hydrochlorofluorocarbons. Proper electronic waste management should focus on removing these pollutants and utilizing them, if possible. The pollutants in electronic waste are listed below:

Printed circuit boards Cadmium, chromium, lead, mercury, beryllium, zinc, nickel, brominated flame retardants, and antimony trioxide can be found in printed circuit boards.
Liquid crystal displays Liquid crystal displays in cell phones and flat panel displays may contain mercury.
Cathode ray tubes Cathode ray tubes contain lead in the glass cone and cadmium, zinc or yttrium sulfide in the fluorescent coating.
Batteries Heavy metals such as lead, mercury, and cadmium are present in certain types of batteries.
Plastic covers Plastics often contain halogenated flame retardants, many of which are hazardous. The combustion of plastics and halogenated flame retardants can produce toxic substances. In addition, antimony is frequently added to improve flame retardancy.
Switches and circuit breakers Mercury is used in fluorescent lamps, thermostats, sensors, relays, and switches.
Welds Welds may contain lead, tin, and other metals.
Internal and external wiring Wires are often coated with PVC that contains different additives, including heavy metal compounds and softeners such as phthalates. The combustion of PVC can also produce toxic substances.
Semiconductors Brominated flame retardants are used in plastic encapsulation materials.

The global increase in electronic device manufacturing and sales have caused a larger generation of electronic waste. During 2016, a total of 44.7 million metric tons of electronic waste were produced worldwide, of which 11.3 metric tons were generated in the Americas. It is estimated that the world’s electronic waste will increase to 52.2 million metric tons by 2021. In the case of Mexico, about 1.1 million metric tons of electronic waste were produced in 2015, making our country the third largest generator behind the United States and Brazil. Mexico’s electronic waste is expected to increase to 1.22 million metric tons by 2021 and to 1.35 million metric tons by 2026, which represents an annual increase of 2.18 percent.

Considering the social, economic, and environmental effects of electronic waste, Mexico must find solutions to the current problems in electronic waste management through the circular economy model. This will support the continuous positive development cycle to optimize resources and processes, as shown in the following image:

Source: Ecolec Foundation


Health Effects

Electronic waste poses a high risk to the environment and human health when handled improperly. Irresponsible disposal of electronic waste favors the production of leachate, which releases toxic chemicals that filter through the soil and contaminate groundwater. Drinking water contaminated with heavy metals affects our bodies and can cause serious health effects such as:

  • Acute poisoning
  • Neurological damage
  • Respiratory tract damage
  • Cardiovascular diseases
  • Liver and kidney damage
  • Osteoporosis and bone deformities
  • Cancer
  • Immunological damage

Electronic Waste Recycling Campaign at UANL

With great concern about this issue, UANL carried out two electronic waste recycling campaigns in 2019 to strengthen its commitment to the environment. The first campaign took place on the World Environment Day in June; the second campaign was conducted on the International E-Waste Day in October. The UANL entities that helped collect electronic waste are listed as follows:

  • Raul Rangel Frias University Library
  • School of Public Health and Nutrition
  • School of Veterinary Medicine
  • High School No. 1
  • High School No. 4
  • High School No. 7
  • High School No. 8
  • High School No. 9
  • High School No. 16
  • High School No. 19
  • High School No. 23
  • High School No. 25
  • Center for Research and Development of Bilingual Education

Likewise, the entities below assisted in the logistics of the campaigns:

  • School of Chemistry
  • School of Accounting and Business Management
  • School of Physics and Mathematics
  • School of Civil Engineering
  • School of Mechanical and Electrical Engineering
  • School of Law and Criminology
  • Department of Learning Service and Internships

A total of 44.0 metric tons of electronic waste were collected in both campaigns. The classification of the collected electronic waste is illustrated in the following graph:

With these recycling campaigns, UANL has accomplished important environmental benefits such as:

The electronic waste was later collected and recycled by an authorized service provider. The money raised during the campaigns will be given to the UANL entity that creates the best sustainable project for their workplace. The invitation to this contest will be issued by the Vice Presidency of Sustainability.

Electronic Waste and the United Nations Sustainable Development Goals

As mentioned earlier, the increasing generation of electronic waste and its improper handling and disposal pose significant risks to the environment and human health. This represents a key challenge to sustainable development and the achievement of the United Nations Sustainable Development Goals. The available hard data on electronic waste could help accomplish some of the 2030 Agenda objectives and different Sustainable Development Goals, particularly those regarding health (Goal 3), economic growth (Goal 8), and the environment (Goals 6, 11, 12, and 14). The specific targets that were set to achieve the Sustainable Development Goals related to electronic waste are described below:

In 2019, the Department of Acquisitions conducted the first stage of a recycling campaign to collect empty toner cartridges at all the UANL entities. Over 1,300 empty toner cartridges were collected and donated to Alianza Anticancer Infantil as part of UANL’s social responsibility commitment. The donations will help fund the treatment of children with cancer.

Organic Waste

The use of organic waste in agriculture plays an important role in soil fertility. Organic waste is a source of nutrients and improves the physical, chemical, and biological properties of the soil. Some of its benefits are higher crop yields, less dependence on farmers, and a reduced use of water, inorganic fertilizers, and pesticides. By improving its properties, soil can resist wind and water erosion, making water penetration easier. This process is an affordable option to enhance soil productivity and increase farmers’ incomes. Other positive effects are less environmental pollution and fewer health risks to farmers and consumers.

The UANL School of Agronomy is currently working on a vermicomposting project at the Marin Campus. The project consists in using worms to break down manure and green waste to produce vermicompost and fulvic acids that are later used as fertilizers for the nursery, experimental cultures, and gardens of the campus. About 1.5 metric tons of organic waste are treated each year, producing 700 kilograms of fertilizer and 1,000 thousand liters of leachate.

Waste Cooking Oil

Waste cooking oil refers to any vegetable oil or animal fat that has been used in food preparation. Its improper disposal is one of the main sources of surface and groundwater contamination: one liter of used oil can contaminate from 1,000 to 10,000 liters of water. When poured down the drain, waste cooking oil can cause clogs, unpleasant odors, and pest proliferation in sewer systems. It can also affect the biological and chemical properties of the soil, leading to negative effects on soil fertility.

For this reason, several UANL entities are now storing waste cooking oil in special containers, which are later collected by the specialized company Sonne Energeticos. From January 2019 to June 2020, a total of 2.5 metric tons of waste cooking oil were collected and reused in ecofriendly products of the chemical and biofuel industries.

Waste cooking oil is frequently treated through a transesterification process consisting of mixing used oil with methyl alcohol and sodium hydroxide. The reaction produces glycerol as a by-product, which can be used to fuel burners and diesel engines or in the pharmaceutical and detergent industries. Biofuels are sustainable alternatives that generate less emissions of CO2 and other greenhouse gases.