By F. Madzima
Chemistry is sometimes referred to as “the central science” due to its interconnectedness with a vast array of other STEM disciplines. Chemistry and the language of chemists play vital roles in biology, medicine, materials science, forensics, environmental science, and many other fields (see diagram below). The basic principles of physics are essential for understanding many aspects of chemistry, and there is extensive overlap between many subdisciplines within the two fields, such as chemical physics and nuclear chemistry. Mathematics, computer science, and information theory provide important tools that help us calculate, interpret, describe, and generally make sense of the chemical world. Biology and chemistry converge in biochemistry, which is crucial to understanding the many complex factors and processes that keep living organisms (such as people) alive.
Chemical engineering, materials science, and nanotechnology combine chemical principles and empirical findings to produce useful substances, ranging from gasoline to fabrics to electronics. Agriculture, food science, veterinary science, and brewing and wine making help provide sustenance in the form of food and drink to the world’s population. Medicine, pharmacology, biotechnology, and botany identify and produce substances that help keep us healthy. Environmental science, geology, oceanography, and atmospheric science incorporate many chemical ideas to help us better understand and protect our physical world. Chemical ideas are used to help understand the universe in astronomy and cosmology. What are some changes in matter that are essential to daily life? Digesting and assimilating food, synthesizing polymers that are used to make clothing, containers, cookware, and credit cards, and refining crude oil into gasoline and other products are just a few examples.
Chemistry plays a very important role in our everyday life. Chemistry is everywhere however many people are not aware of that fact. National development and economic performance is based on chemistry’s strength and its performance. Most developing countries are not aware of that fact. There is no meaningful development without well-structured and organised chemistry field in any country. Zimbabwe is rich with vast natural resources but its economy is performing very poorly. Why? The field that should be controlling and guiding proper utilisation of these natural resources sustainably is incapacitated. That is the chemistry field.
Matter is made up of chemistry, our bodies are made up of chemical compounds and many changes we observe in this universe including climate change are caused by chemical reactions. In our homes, we cook food that’s a chemical process. Chemistry explains why we cook food, how to cook, how it rots, how to preserve, how our body uses food we eat, why we get sick, how to treat sickness. The list is endless. Think about medications and diagnostic consumables, they are all chemicals.
Extractive and processing industries depends on chemistry. If you want to know what is in any material be it soil, rock, wood or any raw material. Chemistry will give you the answer. It will tell you what is it made up of or composed of and their quantities with degree of uncertainty. Proper application of chemistry in this important field can tell all co-existing minerals in case of mining field or harmful substances in case of agricultural produce together with their quantities. This will aid in accounting for everything that is being produced or lost as wastes in any process and also to find ways to minimise their effects be it economically or clinically.
Food security is based on effective application of chemicals such as fertilisers, herbicides and pesticides, proper soil conditioning which is a chemical process and application of suitable water with appropriate quality. Water is polluted by chemicals from the environment, farming activities, mining activities and industrial effluent of which chemistry plays an important role in identification and removal of these pollutants.
Chemistry plays an important role in agriculture and food quality monitoring. Various chemicals are applied to the field for crop protection and nutritional enrichment such as fertilisers and pesticides. They undergo two important processes binding to the soil surfaces (sorption) and degradation in the porous media through either chemical or biological pathways. These two processes govern the fate and transport behaviour of applied chemicals in the environment and are critical for environmental exposure assessments.
Several public databases such as footprint (www.eu-footprint.org/ppdb.html) have accumulated a significant amount of sorption and degradation data from published literature. The majority of these data originated from studies in Europe and North America of which is not a representative of the whole world; thus environmental exposure assessments are often relying on data extracted from region with totally different soil and environmental factors (soil and climatic conditions). Zimbabwe is still lagging behind in this regards and more should be done if the nation wants to adopt scientific driven farming methodologies.
Sorption in soil is a microscopically heterogeneous and time-dependent process which may depend on not only the content but also the chemistry of soil organic matter and mineralogy. Degradation through biological pathways relies on microbial population that are highly localised in the partially water-filled soil pore space and soil pH, with limited mobility to reach out for adsorption substrates. Binding to or release from the soil microscopic surfaces plays a critical role in determining the overall rate of degradation. It is expected that this effect varies with different classes of applied chemical’s chemistry, soil types and climatic zones.
Farmers are encouraged to work closely with chemists so that their farming soil nutritional value is kept constantly at its optimum level all the time thereby increasing their farming yields. This process involves a lot of activities which includes pests and herbs control, soil regulation by optimising nutrients’ redox reaction for sorption process in favour of increasing nutritional bioavailability in soil throughout farming season as well as promoting reduction in chemical residues in the agricultural products.
Exposure to these residues may lead to food poisoning. Generally, exposure is occurring through consumption of food sources with these residues or drinking water contaminated by these residues. Some of the residues have the tendency of building up to harmful levels in hosting species as well as in the environment. The effect may be magnified through the food chain and eventually find their way and end up in meat, poultry, fish and different types of vegetables. Another group of such contaminants include misappropriate use of veterinary drugs. When residues of these drugs find its way to the environment, they may cause an array of human health problems and end up causing second generation diseases such as those caused by antimicrobial drug resistant pathogens.
These residues are not the only sources of food poisons. There are also natural and environmental toxins and contaminants which poses same effects. Such contaminants include lectins, glycoalkaloids oxalates, and cyanogenic alkaloids, mycotoxins and shellfish toxins. Natural toxins in food are of greatest potential risks to human health. Many of them like aflatoxin B1 are carcinogenic and may cause liver damages, such as ochratoxin. Mycotoxins can be found at elevated levels in agricultural products such as corns, peanuts and nuts.
There are also contaminants in food that derive from specific processing conditions. For instance, acrylamide is a known carcinogen and is formed during baking, frying or toasting of various food items. Other such process-derived contaminants include chloropropanols and furans. The involvement of chemists in this regards will significantly minimise exposure rate.
Sustainable food provision involves scientific driven agricultural faming methodologies which promotes increased farming yield of high quality with less harming chemical residues. Sustainable food production is in sync with promotion of good health and abundance of food produce hence the adoption of the word “sustainable”. This can only be achieved by application of appropriate scientific methodologies that will guide proper farming, monitoring and regulating all food provision stages starting from land preparation, planting, harvesting and storage, food distribution and preparation. Methods to be used for official control and monitoring purposes need to be validated against internationally recognised guidelines.
If we could look at United Nations Sustainable Developmental Goals (UNSDGs) of 2015 closely, they are 17 in total of which chemistry directly contribute to the following 12 goals:
No. 1: No Poverty
No. 2: Zero Hunger
No. 3: Good Health and Well-being
No. 6: Clean Water and Sanitation
No. 7: Affordable and Clean Energy
No. 9: Industry, Innovation and Infrastructure
No. 12: Responsible Consumption and Production
No. 13: Climate Action
No. 14: Life Below Water
No. 15: Life on Land
No. 17: Partnerships for the Goals
In goals, number 8 and 16, chemistry contribute indirectly on economic growth and justice. It influences policy making process and implementation. If these UNSDG are to be achieved, chemistry should be given space and time as the major contributor. 97% of products in our markets globally are chemistry products. It is therefore, the major contributor to any economy. Once this critical sector is in disarray there is no product as well as sustainable economic development. At national level, the central government should invite all professional bodies or representatives in case of professions without professional bodies and give them tasks on how (methodologies) each profession can contribute to achieve them. The contributions by professional bodies should then be synchronised to come up with the national guide line on, how and by whom, to achieve these goals.
The Zimbabwe government’s vision 2030 is in tandem with UNSDGs, however they are addressing specific issues that affect Zimbabwe in particular. Chemistry play a key role if vision 2030 is to be achieved. The ZCS can provide methodology on how chemistry can contribute to a specific sector or area in order to effectively and efficiently achieve vision 2030 as a nation. In the coming editions we are going to highlight contribution of chemistry in sector by sector.