Should we abolish the nail polish?

Nail paints have been in fashion for a long long time now. I don’t see them going out of fashion ever, but wait. Are there any chemicals lurking behind the beauty? This is Anuja, pretending to sound like a journalist, from :D

As a kid I had a bad habit of biting my nails. My mom tried to stop me but never succeeded until I started realizing how ugly they look. Back then nail paints were for my toes only. My toes however never took it so well, they’d almost always go yellow after I applied nail paints. Yellowing was caused due to the leftover dyes in the polish. The trick was to use a clear-base coat but I wasn’t that fashion savvy but I know this now.

Applying nail paint was one of the ways to deter me from biting them but out of desperation I would scrap it off with my teeth. I recently advised a friend to do the same but I wondered if any chemicals went into my mouth when I did that. A study led by Duke University and Environmental Working Group suggests that we absorb at least one potentially hormone-disrupting chemical every time we get a polish. What was I thinking putting my nails into my mouth like that?

According to, nail polish could be made of:

  • Nitrocellulose (CAS:9004-70-0) – a film former, the gloss giver.
  • Dissolved in solvents such as butyl acetate (CAS: 123-86-4) or ethyl acetate (CAS: 141-78-6). Toluene, xylene and formalin or formaldehyde used to be in nail polishes as solvents and are infamously toxic.
  • Tosylamide-formaldehyde (CAS: 25035-71-6) and triphenyl phosphate (CAS: 115-86-6) are resins that help the polish adhere to the nails surface.
  • Plasticizers such as Camphor (CAS: 464-49-3, it has some more CAS numbers. According to EPA, a chemical may also be listed with multiple CAS numbers when multiple numbers have been inadvertently assigned to the same chemical. This multiple assignment can occur when forms of a chemical are originally believed to be unique, but after further review by chemists, are identified as the same chemical.) prevent the polish from cracking.
  • A pigment that colors the polish.
  • Titanium dioxide (CAS: 13463-67-7) or ground mica for the sparkles.
  • Thickening agents such as stearalkonium hectorite.

Some of the tools I used to access toxicity of above mentioned chemicals are:

  • Chemical Data Access Tool (CDAT): I did not find this useful. Take the first one for instance and tell me what you see. It won’t even give me anything when I entered ‘nitrocellulose’, I had to look for its CAS number. So I’ve given you the CAS number to find out for yourself and in case you find a new tool and it needs a CAS number. Let me know if you find a new and better tool.
  • ChemHATBlueGreen Alliance has launched a new, free tool that is designed by workers for workers to make it easier to learn about chemicals: ChemHAT (Chemical Hazards and Alternatives Toolbox). With ChemHAT’s searchable database, one can easily read about the scientific findings on the short and long-term health effects of over 10,000 commonly used chemicals. It also lets you search by the CAS number. Couldn’t find nitrocellulose on that one. I have used this the most and have compiled the information of the chemicals below in the form of a slideshow. If you are unable to see let me know and I’ll change the format or solve the issue somehow.
  • Green Chemistry Toxics Information Databases: If you want to try more tools.

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While doing this I wondered how would a common man would do all this. I really think it is the job of the authorities who are responsible for ascertaining the nature of the chemicals used, transparency, and safety of the people. There are people who are paid to do things like this, so why bother the common man with tools that are not even user friendly. There were some chemicals I didn’t even find the information for in those tools. Why? In spite of this, I don’t want nail polishes to be abolished because I like painting my nails occasionally. Here are some eco-friendly nail polishes one can use.

When you are done finding one, you can head over to my cousin’s nail art on Instagram for some cool nail design! She is really good at it. 2016-05-23 14-54-27

And when you are done doing that let me know how going eco-friendly worked for you.

Green engineering principles and applications

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Volunteer Image Author 3Dman_Eu

The word ‘chemical’ has always gained negative attention in the eyes of the public even when it enhances their lives. This is because of the side-effects it causes on the environment due to pollution and toxicity.

Kinds of chemicals:

The chemical industry basically produces 4 kinds of chemicals:

  1. Commodity chemicals: Chemicals that are used by other chemical industries before becoming a consumer product. These are produced at huge scale. For example, petrochemicals produced in a refinery such as olefins and aromatics go on to become polymers.
  2. Fine chemicals: Starting materials for speciality chemicals. These are of very high purity and are produced in limited quantities. Hence these are low-volume, high-value products.
  3. Speciality chemicals: Pharmaceuticals, Dyestuff and pigments, flavours and fragrances, speciality polymers, catalysts and enzymes, food additives. These are consumer products.
  4. Renewable energy: Biofuels such as ethanol, biogas.

Unit operations/processes:

These chemicals are produced using some basic unit operations and unit processes such as:

Unit process + unit operation = an entire chemical process

Unit operations involve physical separation of products that are obtained from unit processes. While unit processes involve chemical conversion of substances.

Some examples of unit processes are:

  • Sulfonation
  • Nitration
  • Hydrogenation
  • Hydrolysis

Unit operations:

  • Fluid flow operations: e.g. fluid mixing
  • Heat transfer operations: e.g. evaporation
  • Mass transfer operations: e.g. distillation, extraction
  • Thermodynamic operations: e.g. refrigeration
  • Mechanical operations: e.g. crushing of solids, sedimentation

Note that these processes overlap i.e. they are interrelated. For example: Evaporation is both a heat transfer as well as a mass transfer operation as it involves the transfer of both heat and mass.

Chemical processes are capable of eliminating the pollution and toxicity that is caused by it. But how? Paul Anastas and Julie Zimmerman developed 12 principles of green engineering. These can be found in Env. Sci. and Tech., 37, 5, 94A-101A, 2003 or at ACS. These are similar to the 12 principles of green engineering because Chemistry and Chemical Engineering are interdependent on each other. Both of them can be viewed side-by-side here.

Green chemistry is the design of chemical products and processes that reduce or eliminate the use and generation of hazardous substances. Whereas, green engineering is the development and commercialization of industrial processes that are economically feasible and reduce the risk to human health and the environment.

Green Engineering:

A chemical engineer needs the following things:

  • Efficiency of the process: It should be efficient in all respects – energy or water efficient for example.
  • Safety of the process: It should be safe to carry out throughout its production line.
  • Financial feasibility of the process: If it is not profitable, it won’t work out.
  • Green engineering knowledge that helps achieve above points

Examples of green engineering:

Integrate Material and Energy Flows: Design of products, processes, and systems must include integration and interconnectivity with available energy and materials flows.

Optimization of heat is crucial for energy savings. Energy savings mean fuel savings. Fuel savings mean less greenhouse gas emissions. Pinch Technology provides such a thermodynamically based optimization methodology for energy saving in processes.

Renewable Rather Than Depleting: Material and energy inputs should be renewable rather than depleting.

Some unit processes/operations require heating. But what if energy comes from a green source? Energy required to heat a process is called as ‘Process heat’. It is often sourced from fossil fuels. A greener option in this case would then be a solar collector that can collect heat to be supplied to the process, termed as solar process heat.

Cogeneration or combined heat and power (CHP) is another technique to save energy. In this, the heat engine or power station simultaneously generate electricity and useful heat.

Some unit processes/operations require cooling. A major coolant in the chemical industry is water. It is used in large cooling towers. It has to be treated and reused since it can be contaminated with chemicals it comes in contact with. These chemicals could also be entrained by surrounded air and cause airborne emission problems. For this purpose, drift eliminators are used –  an air pollution control measure.

Inherent Rather Than Circumstantial: Designers need to strive to ensure that all materials and energy inputs and outputs are as inherently nonhazardous as possible.

A part of my Masters thesis involved catalytic transfer hydrogenation. It is the transfer of hydrogen atoms from a donor reagent to a substrate under catalysis. It is supposedly the safest way to carry out a hydrogenation reaction. Hydrogenation reaction is one of the deadliest of all reactions since it involves hydrogen gas. Hydrogen gas is very light and diffuses into the air very quickly. It is highly flammable too. Not a nice combination. It not only catches fire but spreads wildly. Transfer hydrogenation on the other hand doesn’t require hydrogen gas, it just needs the donor reagent. I think the reason it is not so good to scale-up is because it would need change in existing infrastructure and that comes at a cost.

Another example of safer engineering is eco-friendly coolants. Transformers made it possible for electricity to reach long distances without huge losses. Polychlorinated biphenyls is a banned coolant fluid that was used to cool these transformers. Efforts have been made to produce greener coolants. In 2013, Cargill won the Presidential Green Chemistry Challenge Award from the U.S. Environmental Protection Agency (EPA) for developing  Envirotemp™ FR3™, a eco-friendly coolant. It can be used in high voltage electrical transformers.

Meet Need, Minimize Excess: Design for unnecessary capacity or capability (e.g., “one size fits all”) solutions should be considered a design flaw.

Effluent treatment plants (ETP) often are of the ‘one size fits all’ kind. We call them Common Effluent Treatment plants (CETP). Instead, each plant can have its own ETP. Individual ETPs are more efficient than CETPs.

Design for Separation: Separation and purification operations should be designed to minimize energy consumption and materials use.

Separation and purification operations allow us to recycle materials. To make these operations as energy efficient as possible is therefore necessary. As we know that Pharmaceuticals industry produces highly pure products. Moving bed bioreactor (MBBR) systems are a type of biological treatment that may be utilized in pharmaceutical wastewater applications.

Prevention Instead of Treatment: It is better to prevent waste than to treat or clean up waste after it is formed.

Ultrasonication is another part of my Masters thesis. I basically bombarded a flask of chemicals by ultrasound. In this way, I was able to carry out the reaction without a solvent and at room temperature. This was opposed to previous attempts to carry out the same experiments that used solvents and higher temperature and pressure. As far as industrial applications of ultrasonication are concerned, a company called Industrial Sonomechanics has created industrial scale ultrasonic reactors.

Maximize Efficiency: Products, processes, and systems should be designed to maximize mass, energy, space, and time efficiency.

Microreactors, reactors with dimensions of about 5-100 ml, can run reactions that are not possible to run at large scale. These reactions are often explosive or hazardous in nature. Such a technology when scaled up can lead to material-efficient, energy-efficient as well as safe way to carry out reactions.
Further reading:
Excellent review: New trends for design towards sustainability in chemical engineering: Green engineering, J. Garc´ıa-Serna et al. / Chemical Engineering Journal 133 (2007) 7–30

New in Green Chemistry: The Zipper approach

Many chemical products can be produced via different routes. One of these routes may be industrialized depending upon its cost-effectiveness, satisfaction of environmental constraints and ease of scale-up. As you may be aware, environmental constraints have become stringent due to the effects the chemical and allied industries have on our environment. Green Chemistry, with its 12 guiding principles has made the world look at conventional chemistry and its subsequent scale up with a fresh approach that is environmentally benign.

In 1990, Elias James “E.J.” Corey, an American organic chemist won the Nobel Prize in Chemistry for his development of the theory and methodology of organic synthesis, specifically retrosynthetic analysis. The most famous of all the restrosynthesis processes is the production of Ibuprofen, wherein 6 steps were reduced to just 3. This achieved one of the 12 principles of Green Chemistry that says, “Unnecessary derivatization (use of blocking groups, protection/ deprotection, temporary modification of physical/chemical processes) should be minimized or avoided if possible, because such steps require additional reagents and can generate waste.”

Synthesis Explorer by the Royal Society of Chemistry (RSC) helps students and teachers plan synthetic routes by choosing a starting compound, reacting it and viewing details of the reaction.

According to Warner, only 10 percent of current technologies are environmentally benign and 35 percent could be made benign relatively easy. The remaining 65 percent will need to be reinvented in more environmentally benign ways. A report by Lisa Lilleland, a sustainability advisor and environmental advocate.

Retrosynthesis is design of organic synthesis to find newer, simpler and benign ways to produce a compound. Technion Scientists have now developed a new method for selective synthesis of complex molecules. They call it the “Zipper Approach”. It is a one-of-a-kind stereochemistry for difficult transformations: allylic C-H (H=Hydrogen) and selective C-C bond activations. The paper is published in the journal Nature.

More and more companies are now offering services in upscaling and route scouting. Route scouting is the creation of sustainable synthesis routes. Some of the companies that provide such services are:

Safety first with green chemistry

One of the most important parts of doing green chemistry is making the chemistry safe. Doing it safe comes in three parts: Firstly, the products that are made should be safe for the consumers. Secondly, and sadly, the neglected or less seriously taken part, is the safety of those who make these products, at any level of the production line – workers and their neighbors. Thirdly, researchers in a laboratory.

Let’s take an example. Let’s say you are an researcher in a lab, or may be just a college student. What will you do if sulfuric acid spills on the floor? Do you have any idea? Good if you do, but if you don’t here’s what you can do:

  • Put sand on it.
  • Collect it in a tray.
  • Add base: NaOH + H2SO4 = violent. So, we are not going to add NaOH. We’ll have to use another base, that is Na2CO3. Even better if you have CaCO3.

Safety education is very important, you see?

Who makes sure that workers are safe? Legislation and organizations do and every country has its own of doing it. Here’s a list of them:

  1. European Union: European Agency for Safety and Health at Work (Read about REACH here.)
  2. UK: Health and Safety Executive and local authorities (the local council) under theHealth and Safety at Work etc. Act 1974
  3. Denmark: The Danish Working Environment Authority
  4. US: National Institute for Occupational Safety and Health (NIOSH) and the Occupational Safety and Health Administration (OSHA)
  5. Canada: The Canadian Centre for Occupational Health and Safety (CCOHS)
  6. Malaysia: Department of Occupational Safety and Health (DOSH)
  7. People’s republic of China: Ministry of Health is responsible for occupational disease prevention and the State Administration of Work Safety
  8. South Africa: Department of Labour
  9. India: National Safety Council (NSC)

Although the NSC was set up in 1966, Bhopal disaster that occurred in the year 1984 brought even more attention to the importance of safety, not only in India but worldwide. Human loss is also accompanied by monetary loss for the plants involved. “A safe plant is a more profitable plant.”Walt Boyes. One cannot ignore the financial risk that involves with every accident. In financial terms, these risks are known as ‘contingent costs’. Contingent costs include penalties, remediation, personal injury damages etc. Not to mention the damage that is caused to a company as its corporate image and relationships are at risk as well. Take the example of Hindustan Unilever, when its workers were exposed to mercury in the thermometer factory it owned in Kodaikanal. It shut down in 2001.

Now here we are looking at the bigger picture, to keep it all safe. ‘Life Cycle Analysis’ (LCA) gives us that bigger picture. There are softwares out there that can help a company and there are companies which are already at it.

LCA softwares include:

  1. SimaPro
  2. Umberto
  3. GaBi

You will find some more here:

  1. EPA‘s LCA resources

Companies involved in LCA:

  1. Bristol-Myers Squibb
  2. BASF’s Eco-Efficiency Analysis

Learning from nature

Why make our own mistakes when we can learn from nature? Through unfathomable amounts of trial and error that nature has gone through, it would only be wise to learn how nature does what it does. Biomimicry is what we name – our process of learning from nature. The earliest of examples of biomimicry has been the making of an aeroplane. It is when we tried to see how birds do it is when we understood how humans could fly too. Sonar technology was invented after studying the echolocation that bats use to navigate.

2013-09-07 17.34.53 (1)Green Chemistry and Biomimicry:

Green Chemists too can learn from it as sustainable chemistry is what nature is good at. Nothing goes to waste you see? It is in nature lies the secrets of producing inherently safer chemistries. The enzymes that are at work in our body right now are natural catalysts. This gives rise to bio-catalysis. Learning from corals that fix carbon to create vaccines that do not need refrigeration are few of the many applications that have their origins in biomimicry.

Let’s also see how nature has inspired industries.

Paper and pulp industry:

Paper is made from wood fibres that are bonded together by a natural adhesive known as lignin. Lignin must be removed in order to make paper. While one may think of lignin as waste, it is not. Lignin after separation is used for producing other chemicals and may be also to produce an oddly sounding product called ‘liquid wood‘, a plastic replacement. This entire process is called ‘pulping’ and is done through physical and chemical processes. These processes are water and energy intensive. To ensure that less water and energy is used, scientists have come up with a solution that uses a deep eutectic solvent. These solvents occur naturally: plants produce them during droughts.  Not only that, these scientists used the genius of penguins to solve the problem of high water usage during the drying process that follows pulping. To escape from seals underwater, these birds release trapped air bubbles which form a thin layer of air around their plumage, reducing friction. This gave the researchers an idea to suspend the fibres in a viscous fluid and then expel the fluid by modifying the viscosity around the fibres.

Fuel industry:

Plants are very efficient machinery that can store sunlight directly into storable chemical form. Researchers led by a MIT professor produced something known as a ‘artificial leaf’, a device that can harness sunlight to split water into hydrogen and oxygen without needing any external connections, just like leaves do.

Solar industry:

In the field of solar energy, plants are an exemplary. Have you seen the sunflowers move as they track the position of the sun in the sky for maximum absorption of solar energy? That’s something to learn from and scientists have come up with sunflower-inspired solar panels that track the sun without using motors. Another example of biomimicry in this industry are the dye-sensitized solar cells, that are solar cells inspired by photosynthesizing plants.  Along similar lines, researchers at the Institute of Chemical Technology (ICT) (the institute I majored from) have developed 18 synthetic dye molecules, which can be used to make indigenous dye-sensitised solar cells (DSC) that absorb solar energy.

Windmill industry:

To reduce the drag in wind turbines, some researches decided to use the riblet technology. The channeling effect was first noted in shark skin research in the 60s and 70s, which was first studied by NASA to incorporate it into aerospace engineering.

Water-treatment industry:

Discovery of aquaporins, integral membrane proteins that form pores in the membrane of biological cells, are nature’s very own filters. Inspired from this a Danish company Aquaporin has developed a new approach to seawater desalination.

To know more about such extraordinary lessons on conservation of material and energy, go to AskNature.

Here’s a mind boggling video of the physics of water in trees. Do you think we can take away something from this as well?

E. coli, the green celebrity!


Escherichia coli or more commonly known as E. coli, according to me, happens to be the celebrity of the green world when it comes to biology in green chemistry. These are the friendly bacteria that live in our guts and help digest our food. Although, some of its strain do cause problems to us. It’s time to give it some positive attention. Scientists genetically engineer E. coli and greenify a chemical reaction.

Here are a few examples of how they did it:

  1. Reduction of GO: Microbial reduction of graphene oxide by Escherichia coli: A green chemistry approach
  2. Cleaner chemistry: Transplanting metabolic pathways into E. coli
  3. Biofuels: Turning bacteria into butanol biofuel factories
  4. Turning waste into fatty acids: Genetically Modified E. coli Bacteria Turn Waste Into Fat For Fuel!
  5. Sugars into biofuels

The Presidential Green Chemistry Challenge Award Recipients included individuals/organizations who used E. coli. Here are some entries:

2012 Codexis, Inc.; Professor Yi Tang, University of California, Los Angeles LovD, an acyltransferase from E. coli engineered by directed evolution, now performs regioselective acylation in the sysnthesis of the drug simvastatin (summary)
2011 BioAmber, Inc. Genetically engineered E. coli strain licensed from the Department of Energy produces succinic acid from wheat-derived glucose on a commercial scale (summary)
2011 Genomatica Genetically engineered E. coli strain produces 1,4-butanediol by fermentation of readily available sugars (summary)
2011 BioAmber,Inc. Glucose is fermented on a commercial scale by a genetically engineered E. coli strain to make succinic acid, traditionally produced from petroleum (summary)
2011 Genomatica Readily available sugars fermented by a genetically engineered E. colistrain produce 1,4-butanediol, a large-volume chemical usually made from petroleum (summary)

The world outside our guts is far harsher for these bacteria, especially in our reaction flasks. So what are scientists doing about it? They are making hospitable environments for these little celebrities. Making safer solvents for them is one way. But is E. coli losing its shine? Time will tell.

Read more:

How yeast replaced E. coli: BioAmber phases out E.coli use