Want to be an aerosol scientist?

David Ng’ang’a, 27, is studying aerosol science at the University of Nairobi. Aerosol science is a discipline specialising in monitoring air quality and chemical elements in the air.

It is one of the upcoming careers today and is poised to become popular due to climate change and modern human social and economic activities including industrialisation and urbanisation.

The career involves lots of research, and one has to work under the supervision of an accomplished mentor in this field.

Ng’ang’a is working under the supervision of a professional he looks up to, Prof Michael Gatari, himself an aerosol scientist, nuclear science specialist and the director of the Institute of Nuclear Science and Technology at UoN.

To help hone his skills further, the University of Nairobi awarded Ng’ang’a a scholarship in 2016 to pursue a masters in nuclear science, a year after attaining a first class honours in his Bsc (Chemistry) from the university in 2015. Ng’ang’a, who scored A- in his Kenya Certificate of Secondary Education exams, plans to pursue a PhD in Aerosol Science.

After his undergraduate course, he spent his leisure time teaching a group of young people how to make detergents in Nairobi’s Ongata Rongai, where he lived at the time.

“During our undergraduate course, we learnt how to make detergents. I singled out five young people who were determined to be self-employed and volunteered to teach them how to make detergents for sale.”

He also passed on this skill to a group of women who included his grandmother; Ms Salome Wanjiru, and was in the process of starting his own company when he was offered a masters scholarship.

What influenced you to study aerosol science?

I am passionate about understanding the world and the universe. I chose to study chemistry in my undergraduate because, as the base science, chemistry explains the beginning of things that we see in atom form. In addition, I am keen on the environment and have been a member of environment clubs right from primary school to university.

What changes do you want to make in your community?

I want to make people aware of atmospheric risks due to air that has not been well cared for. I want to do this based on scientific, verifiable, well-researched information. This will leave nobody in doubt about the advantages and disadvantages of a well taken care of atmosphere.

What job opportunities are there for an aerosol scientist?

One can work as a climate change consultant, in the green energy sector, pollution mitigation, in industrial and occupation policy development, and as a researcher. Other opportunities include inter-related disciplines such as urban planning, industrial designing, environmental conservation, among others.

You are currently involved in a research with the Air Quality Lab of the Institute of Nuclear Science and Technology. What exactly are you doing?

I assess the level of pollutants in the atmosphere and the chemical components in the air. I do this using nuclear techniques. For example, by using an equipment known as an X-ray Fluorescence, I am able to identify the chemical elements in the air. From that, I am able to deduce which chemicals they are and even determine their level of concentration.

What have you discovered during your analysis?

That we have elements in the air which can be harmful to the body and its systems if inhaled, thus we need to study the air quality more and advise on ways to reduce pollution through policies, personal hygiene, and environmental conservation interventions.

In another study that involved an assessment of emissions from an open fire cooking method and that of an ordinary charcoal stove (jiko), I found that both methods have a fairly high concentration of fumes that can lead to respiratory related illnesses.

What determines better air quality from bad one?

The World Health Organisation (WHO) has set standards on the quality of air people should breath in. This reasoning is advised by the fact that small-sized chemical particles suspended in the air are more likely to be inhaled in large quantities, while bigger chemical particles would be less inhaled, in a given volume of air.

What are you currently researching on?

I am involved in a project, within Nairobi, to assess the types of chemical elements that could be suspended in the atmosphere. This will help to determine the level of pollution and the likely source of pollutants.

The study is a collaboration of the UoN with UK’s University of Birmingham.

I am using a device known as Optical Particles Counter (OPC). It has a sensor that emits laser light. The light scatters when it comes into contact with particles in the air. You can use the device to evaluate what is in the air.

As an aerosol scientist in the making, what challenges do you foresee in future?

Kenya has a problem of waste disposal. Some of it includes plastic materials that contain highly toxic material known as polycyclic aromatic hydrocarbons (PAHs).

When burned, plastic releases endangering chemicals in the air that have an ability to alter the normal body genetic set up, something that could expose one to cancer-related carcinogens. Industrial waste is generally known to have ammonia, hydrogen-sulphide, lead and carbon monoxide, which are equally lethal.

Who is responsible for the mess?

The national government, counties and citizens. Looking at our towns, city streets, residences, schools, universities and other public places gives you a clear picture of what it is.

The national government is supposed to ensure that policies are in place to safeguard the safety and health of the people as they carry on with sustainable livelihoods, but county governments should implement the rules and safeguard the environment within their jurisdiction.

The citizens should patriotically see that waste is put in the rightful place and disposed as recommended.

What is the solution?

The nation should take the matter of waste disposal seriously. Mostly, we don’t give much thought to waste disposal. Although we have fairly good policies that offer a starting point towards an improved chemical and organic waste disposal system, we do not adhere to it.

We dispose waste in unauthorised areas such as in our rivers, lakes, ocean or burn it openly within human populations and activities.

The institutions charged with environmental watch should educate the public and carry out public advocacy consistently.

Ordinary Kenyans should be made aware of the risks involved when you burn waste with unknown chemicals.

Who do you look up to?

My grandmother. When I was demoralised because I could not go to the secondary school of my choice, she told me: “You can make it in any other school since your head is still the same.” I made it.

What career advise do you have for fellow young people?

When choosing a career, explore ways of creating opportunities out of it.