Manufacturing soap from waste oils: an opportunity for waterways and health

The course “Soap making from waste oils” of the UNESCO Water, Women and Development Chair, is a way to learn how to reduce the impact of this waste on surface waters, an opportunity for economic income and a contribution to the prevention of COVID-19

The COVID-19 pandemic is a reminder that, for a healthy life, access to safe water and sanitation is a right for all. It also recalls that hygiene is basic to preventing many diseases, in particular the use of soap, which inactivates and eliminates the virus, through the chemical concepts of hydrophilicity and hydrophobicity:

“The way in which hydrophilic substances are added to each other and avoid contact with hydrophobic substances (the so-called hydrophobic effect) makes soap literally dismantle this and many other viruses” (FERNANDES; RAMOS, 2020, p. 151).

However, there are cases where access to soap is not easy.

Is it possible to generate hygiene products from home and at the same time reduce water contamination? Yes, household oils are sometimes disposed of in the drains, causing contamination of watercourses. However, these oils can be transformed into soap.

In order to obtain soap from waste oil as a cost-effective, low-cost product and above all to help reduce environmental impact, experts who know the science behind its preparation have come together to offer an accessible and open production course.

Dr. Vera Guarda, who coordinated the UNESCO Chair on Women’s Water and Development, tells how they are running the course on “Soap production from waste oil”.


How did the idea of training in soap production from waste oils come about?

The idea is not new. In a not too distant time, older people were already doing it, especially those living in rural areas. My mother, for example. She used pig fat and ash from the wood stove. I would say that the course is a rescue of traditions, knowing how to make soap from generation to generation.

At the UNESCO Water, Women and Development, we needed to call the attention of women for the preservation of water resources, and several ideas for training courses came up. It was also during a survey on the washing of domestic water tanks, that women requested training courses in order to obtain an income. This led to several courses, including one on soap production, which was an idea of Professor Ângela Andrade of the Department of Chemistry at the Federal University of Ouro Preto UFOP.


What is the environmental impact of waste oils discharged into watercourses?

As oil is less dense than water, it remains on the surface of rivers and lakes, preventing the entry of light and oxygen. This causes the death of several aquatic species, such as phytoplankton (microscopic algae that live in rivers and seas and produce oxygen) that depend on light to develop and survive. This can have serious consequences, since phytoplankton are at the base of the food chain in aquatic ecosystems, serving as food for larger organisms that can also die. In addition, they are believed to produce about 98% of the oxygen in the Earth’s atmosphere.


How does this course help vulnerable women, and society as a whole, in times of pandemic?

While anyone can do it, this course is particularly aimed at women in situations of economic and social vulnerability, who can make soap for their own use and even sell it in the neighbourhood. The cost of production is not very high and the profit is excellent.


This course has already been given in situ, could you tell us where, and what the impact was?

The course on artisan soap production has always been held in Ouro Preto, as an extension project for the Nucleus of the Chair. The most important impact was that it led women to talk about the conservation of water resources. In addition to the soap-making course, they received notions of environmental education and organizational psychology, the curriculum, the importance of self-esteem, etc. Therefore, they were also trained to obtain a job option.

We have a very interesting story of a master’s student with experience in pharmacy who used the handmade soap-making activity as a way to reduce the use of antidepressants in women in the city of Presidente Juscelino, a small town where men travelled to larger cities in search of work and some women began to feel depressed. With the manufacture of the soap, they met, talked during production, gained a small income, started to work, and reduced the consumption of the drug.

Another case was the creation of the Associação Mãos que Brilham in the district of Antônio Pereira, one of the oldest villages in Ouro Preto. Marked by mining and the influx of men who were hired to work in mining, women did not have many opportunities. The soap course was very good and allowed us to win the Santander Universidade Solidária prize. With the prize we managed to found the association