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Chemicals are part of everyday life. According to the International Labour Organization, there are between 5 and 7 million known chemicals in the world and at least 400 million metric tons of them are produced each year.

However, chemicals pose a wide array of risks to human health such as eye, skin, or respiratory irritation, damage to the immune, respiratory, cardiovascular, nervous, reproductive, or endocrine systems, and congenital or chronic diseases, including cancer. Moreover, chemicals also have potentially hazardous effects such as flammability, corrosion, water and soil pollution, and aquatic toxicity. Many fires, explosions, and other disasters result from inadequate control of their physical and environmental hazards.

The best way to manage chemicals is to make an inventory in the different departments, check if they are properly labeled, classify them by incompatibility, and keep their safety data sheets updated with the correct information on risks and safety procedures. Other important considerations are using personal protective equipment when necessary, training occupationally exposed workers, medical surveillance, and safety procedures for the proper transportation and final disposal of chemicals.

In 1992, the Globally Harmonized System of Classification and Labelling of Chemicals was established at the United Nations Conference on Environment and Development in Brazil thanks to an initiative by the International Labour Organization. Likewise, Mexico created the Official Mexican Standard NOM-018-STPS-2015 in order to establish a harmonized system of hazard identification and communication in the workplace to protect employees and emergency workers.

This standard applies to workplaces that use, transport, transfer, store, or process hazardous chemicals. It is not applicable to consumer products, pharmaceuticals, food additives, cosmetics, pesticide residues in food, and hazardous waste.

The harmonized system of hazard identification and communication must meet the following criteria:

  1. The list of hazardous chemicals and mixtures in the inventory, including:
    • Chemical name
    • CAS number
    • Physical and health hazard classification
  2. The safety data sheets with all 16 sections.
  3. Labels including:
    • Chemical name
    • Signal word
    • Pictograms
    • Hazard statements
    • Precautionary statements
  4. Training for employees and emergency workers at least once a year and every time a new hazardous chemical is added to the inventory or the safety data sheets and labels are updated.

Safety Data Sheet Sample:

Label Sample:

Pictograms alert users of the potential hazards of chemicals and mixtures in the workplace. Each pictogram consists of a black symbol on a white background framed within a red border. The classification criteria for health, physical, and environmental hazards is presented below:

The Globally Harmonized System enables a better communication of chemical hazards and the proper handling of chemicals, ensuring their safer use at home and in the workplace.

Chemicals Used in Everyday Life

Before choosing cleaning products or antimicrobials, it is important to know their intended purposes: cleaning, sanitizing, or disinfecting. In most cases, surfaces should be cleaned before being sanitized or disinfected. There are several aspects to consider when selecting products; different surfaces require different products and methods to eliminate microorganisms.

Some infectious diseases are spread through respiratory droplets, sprays, or direct contact with fomites. Disinfecting or sanitizing surfaces will not necessarily prevent the transmission of these diseases. The only way to prevent their transmission is to follow the existing sanitation protocols.


Cleaning removes microorganisms, dirt, and grime from surfaces and objects. Dirt and organic matter make disinfecting less effective. Therefore, in most cases, surfaces should be cleaned with soap and water before being sanitized.


Sanitizing reduces the number of viable particles on surfaces (any particle that contains one or more living microorganisms) by means of chemical agents that kill microorganisms and pathogens. Sanitizing should always come after cleaning.


Disinfecting with chemical agents or physical methods kills most microorganisms on food, drinks, or food supplements without compromising their safety and properties. Disinfecting will not necessarily eliminate spores.

The excessive and irresponsible use of these products may represent a risk to human health and the environment. Some products cause microorganisms to mutate, allowing them to resist certain disinfectants.

Improper sanitizing and disinfecting include:

  • Using disinfectants on surfaces that have not been previously cleaned.
  • Wiping clean or rinsing surfaces before the end of the listed contact time.
  • Diluting concentrates in a ratio that is not indicated on the label.

For this reason, the Environmental Protection Agency (EPA) created an infographic with six steps for safe and effective disinfectant use:

  1. Check that your product is EPA-approved.
  2. Read the directions.
  3. Pre-clean the surface.
  4. Follow the contact time.
  5. Wear gloves and wash your hands.
  6. Lock it up.

A list of EPA-registered disinfectants was also published. These products have qualified under the agency’s emerging viral pathogen program for use against COVID-19 and contain the following active ingredients:

  • Sodium hypochlorite
  • Phenolic
  • Ethanol
  • Isopropanol
  • Quaternary ammonium
  • Hydrochloric acid
  • Hydrogen peroxide
  • Silver ion
  • Citric acid
  • Iodine
  • Peroxyacetic acid

The above products are for use on surfaces only and should not be mixed. Label directions must always be followed for their safe and effective use.


Fumigation is the process of releasing a gaseous fumigant into a sealed structure to eradicate pests. This procedure is conducted in sealed areas to prevent the applied fumigant from escaping.

Pest control refers to keeping pest populations at a level where they do not represent a threat to humans, animals, or plants. This process also involves the use of pesticides and disinfectants. Pest control services are carried out in places such as houses, health centers, childcare facilities, factories, shops, markets, offices, gardens, streets, and public spaces, among others.

In Mexico, all pest control service providers must comply with the sanitation guidelines established by the Official Mexican Standard NOM-256-SSA1-2012. Similarly, disinfection and sanitation service providers must prove they follow best practices for disinfectant use by meeting the requirements of the Federal Commission for the Protection against Sanitary Risks (COFEPRIS) and passing the verification visits.

Chemicals can cause different effects on all the human body systems depending on the route of entry, the exposure time, the number of exposures, the physical state (solid, liquid, or gas), and the susceptibility of people to those chemicals.

Failure to take precautions when handling chemicals may lead to serious damages to health including skin, eye, or respiratory irritation, skin color changes, liver and kidney damage, mutagenicity, cancer, and even death.

Therefore, the proper management of hazardous chemicals and materials is of utmost importance to reduce health and environmental risks. It should be considered that chemical contaminants can spread easily and have global consequences.

In this context, UANL is currently encouraging entities to comply with the NOM-018-STPS-2015 standard since thousands of students, professors, and employees take part in academic, research, or maintenance activities at laboratories, workshops, or printing facilities where chemicals are used. Several courses and conferences are being held to train the staff involved in the management of hazardous chemicals and materials.

Furthermore, the Vice Presidency of Sustainability published Sustainable Guidelines on Workshops and Laboratories on its website. These guidelines provide information about waste and chemicals management.