This article covers some important questions regarding the degradability and environmental impact of acetic acid. The following topics are addressed:
- Is acetic acid biodegradable and to what extent?
- Are there any health hazards associated with acetic acid
- What is the environmental impact of acetic acid
- Can it be reused in any way?
- What are the applications of acetic acid
Is Acetic acid biodegradable?
Acetic acid is biodegradable because it is highly soluble in water and quickly disintegrates into acetate and hydrogen ions when mixed with an aqueous solution meaning it will not remain in the form of acetic acid in water for long hence it does not bioaccumulate.
However, because of its dissociation, there is one limiting factor it can not be reused once it is disassociated.
Acetic acid is natural because it is produced naturally by many organisms such as bacteria through the process of fermentation. It is the main ingredient in vinegar and many other food items. Therefore, it is regarded as eco-friendly unless it does not interact in its intact form.
To properly dispose of acetic acid, it is advised to dilute it and then pour it into the drains. Unsustainable amounts of acetic acid are avoided because it can cause changes in the pH of water due to the presence of hydrogen ions which have been known to be mildly toxic for marine life but if the concentration increases continuously, it will become an imminent threat to marine life.
How readily can acetic acid degrade?
Acetic acid is readily biodegradable in nature with almost 96% degradation in less than 20 days. It is highly soluble in water and quickly disintegrates into acetate and hydrogen ions when mixed with an aqueous solution meaning it will not remain in the form of acetic acid in water for long hence it does not bioaccumulate.
Biodegradability is the ability to be degraded by microbes so that there is less waste generation and accumulation. It is an effective parameter to assess how eco-friendly or sustainable a product is because if a product is biodegradable, it will contribute less to environmental problems.
There is a general rule of thumb about biodegradability natural materials are more prone to biodegradation as compared to non-natural materials. The same is the case for acetic acid. Let us probe further into whether acetic acid is natural or non-natural.
Is it natural?
Yes, it is natural because it is produced naturally by many organisms such as bacteria through the process of fermentation. It is the main ingredient in vinegar and many other food items.
However, almost 90% of acetic acid produced today is synthetically made due to high demand in multiple industries. The biological way of producing acetic acid is not only expensive but time-consuming as well but it does not mean that it loses its status of being biodegradable. Synthetic acetic acid is as biodegradable as natural acetic acid.
Is it eco-friendly? (Effect on plants)
Yes, considering the fact that acetic acid quickly dissociates in an aqueous solution it means that it does not reach the plants as intact acetic acid through freshwater channels.
However, if it were to reach completely intact, still several studies have reported that acetic acid has a very low potential for absorption in soil and sediment meaning it does not hold up in soil so it does not affect the plants in any way.
Still, one thing cannot be ignored an increase in acetic acid concentration in water provides hydrogen ions to the water which affects its pH and increases the acidity of water which may affect plant growth.
Are there any health hazards?
No, not as such but as there is a famous saying “Excess of anything is bad”. Acetic acid itself does not pose any real threat as it is biodegradable but it has been reported that increased production and use of acetic acid due to rapid urbanization contributes to increased acidity in rainwater which may be alarming.
Another important concern regarding the increased concentration of acetic acid fumes in the air is that acetic acid in high concentration is corrosive to human skin and causes blisters and burns which appear after several hours of exposure. Also that acetic acid is a flammable liquid so extra care must be taken while dealing with it in concentrated form.
Is it reusable?
Yes, it is reusable “as-is”, which means that it can be used several times if it does not dissociate but as discussed earlier, it dissociates into acetate and hydrogen ions when mixed with an aqueous solution.
Many studies have been done and are currently under progress to recycle used acetic acid and to filter out acetic acid from wastewater which has not yet disintegrated. Reusing or recycling acetic acid is important because a lot of energy is required in its synthetic manufacturing.
How to dispose of it properly?
Concentrated acetic acid is dangerous and must not be thrown as-it-is in the drain, rather a more safe procedure recommended by the Environmental Protection Agency (EPA-US) is to dilute the acetic acid by adding water and then pouring it down the drain. In this way, most of the acetic acid dissociates and becomes harmless.
In laboratory settings, it is recommended to burn acetic acid in a mechanical incinerator, that way harm can be avoided.
What are the applications of acetic acid? (3 applications in the food industry)
Acetic acid has broad uses in several industries but here we shall mention two of the most important industries that use acetic acid. The medical field and food industry
Acetic acid has a lot of uses in the medical field. The most important use here is that:
- It can be used as an antibiotic against several bacterial species.
- It has been and is used in cervical cancer screening.
- Before the examination of white blood cells, acetic acid is used to destroy red blood cells.
- Acetic acid in the form of vinegar has been known to have several health benefits which include the reduction of high concentrations of blood sugars.
Acetic acid has the following but is not limited to uses in the food industry:
- The food industry has the most uses for acetic acid where it is used in almost every type of packaged food such as ketchup, mustard, and mayonnaise.
- It is also used in making pickles and it works very well as a pickling agent.
- Acetic acid is used for various seasonings and also to make baked goods
How does acetic acid contribute to the environmental problem?
Acetic acid does not have any direct impacts on the environment as discussed earlier it does itself cause any harm to marine life, it is biodegradable and degrades very quickly, it does hold up in soil and sediment so it does actually affect plant life as well but the real environmental impact lies in the sphere of indirect impacts.
Firstly, commercial production of acetic acid is mostly done through the chemical synthesis of acetic acid in a process known as methanol carbonylation. In this process, methanol and carbon monoxide react to form acetic acid but the process is costly as it requires a consistent temperature of 150-200℃ and pressures of 30-50 bar.
The global need for acetic acid currently stands at 15 million tons per year and is continuously rising. Now, this high energy demand for commercial production translates into more fossil fuel burning increasing environmental impacts.
Secondly, the uncapped addition of acetic acid in water changes the pH of water due to the presence of hydrogen ions which have been known to be mildly toxic for marine life but if the concentration increases continuously, it will become an imminent threat to marine life.
Lastly, acetic acid is naturally found in the air as fumes but its increased concentration is harmful to humans. Although it is not a part of acid rain, it contributes to the acidity of the rain.
Acetic acid and crops?
Acetic acid does not affect crops as discussed earlier it has high mobility in soil and sediment and it does reach in the intact form if it reaches through water so it does not impact crops in this way but the only possible concern remains the increase of acidity of water being supplied.
Conclusion
It is concluded that acetic acid is biodegradable because highly soluble in water and quickly disintegrates into acetate and hydrogen ions when mixed with an aqueous solution meaning it will not remain in the form of acetic acid in water for long hence it does not bioaccumulate.
However, because of its dissociation, there is one limiting factor it can not be reused once it is disassociated.
Acetic acid is natural because it is produced naturally by many organisms such as bacteria through the process of fermentation. It is the main ingredient in vinegar and many other food items. Therefore, it is regarded as eco-friendly unless it does not interact in its intact form.
To properly dispose of acetic acid, it is advised to dilute it and then pour it into the drains. Unsustainable amounts of acetic acid are avoided because it can cause changes in the pH of water due to the presence of hydrogen ions which have been known to be mildly toxic for marine life but if the concentration increases continuously, it will become an imminent threat to marine life.
Frequently Asked Questions: Is Acetic acid biodegradable?
How readily does acetic acid degrade?
Acetic acid is readily biodegradable in nature with almost 96% degradation in less than 20 days.
Is Acetic acid natural?
Yes, it is natural. It is produced naturally by many organisms such as bacteria through the process of fermentation. It is the main ingredient in vinegar and many other food items.
References
- Avery Jr, G. B., Tang, Y., Kieber, R. J., & Willey, J. D. (2001). Impact of recent urbanization on formic and acetic acid concentrations in coastal North Carolina rainwater. Atmospheric Environment, 35(19), 3353-3359.
- Raj, C. C., Ramkumar, N., & Chidambaram, S. (1997). Biodegradation of acetic, benzoic, isophthalic, toluic and terephthalic acids using a mixed culture: effluents of PTA production. Process safety and environmental protection, 75(4), 245-256.
- Risk assessment report of acetic acid. Retrieved from https://www.santos.com/wp-content/uploads/2021/04/Acetic-acid-23-March-2021.pdf
- Sherertz, Peter C. (1994). Acetic acid. Virginia Department of Health Division of Health Hazards Control.
- Deshmukh, G., & Manyar, H. (2020). Production Pathways of Acetic Acid and Its Versatile Applications in the Food Industry. In T. P. Basso, T. O. Basso, & L. C. Basso (Eds.), Biotechnological Applications of Biomass. IntechOpen. https://doi.org/10.5772/intechopen.92289