Water

The Chemistry of Water and the environment

By Andrew Glory Mtewa

 

Water is one commodity, usually taken for granted, whose value people realize when it becomes scarce. In its abundance, nobody dares to look after and care for it.

Water is the basic necessity for life of animals and plants.

It is essential for chemical dissolutions, transportation and sometimes cooling. Water becomes scarce due to drought, and pollution among other factors. An environment is conducive to life if it has un polluted water.

In this article, I will concentrate on how adverse it is to life to neglect pollution of water in our environment with a few suggestions that can help us manage pollution of water in our local setting. I will briefly tackle both water and effects of careless waste dumping in our environments including agricultural chemicals management.

 

It is widely known that water has two basic components which are hydrogen atoms and an oxygen molecule (H₂O). However, there are ideally some other elements that are found in the water that we use from time to time. Water may also contain metals and salts, acids and bases.

If we do not take care of the water bodies that we have, the water becomes po0lluted.

 

Sources of water pollution

 

Presence of agents of water-borne infectious diseases and toxic chemical components in water are major threats of water pollution. The microbes when multiplied cause major epidemics like cholera and typhoid fever. These are common in areas close to rivers, swamps and dams. Water bodies In areas close to plants that use or produce chlorides, i.e. sewage, life in water is affected by some chloride salts like trihalomethanes which is a hazardous chemical. Other chemicals are as follows:

Lead (Pb)

Lead is very common in household water. As time goes, lead gets eroded from the pipes, if they were made with some lead, through a process called plumbosolvency. This is due to force from constant fast running water within some range of pH and temperature variations. Too much lead affects the neuro-physiology of animals resulting to disordered behaviour.

Nitrates (NO₃^-)

Nitrates tend to pollute our water systems particularly from the use of nitrogenous fertilizers and a bit from the changes from pasture land to arable lands in low lying lands close to water bodies. Too much nitrates from water into the blood systems reduce oxygen carrying capacity. Formation of N-nitroso compounds, a toxic compound from nitrogen may be carcinogenic to animals.

Pesticides

These are essential as they are used to control living organisms in agricultural outputs. However, if they are improperly handled, they may be exposed either deliberately or by accident. In rainy seasons, when farmers are busy applying various pesticides in their fields, some of the remains of the pesticide chemicals are washed away to low lands and eventually pollute water in bore holes, as a case of rural areas and rivers.

 

The sad thing in polluting water bodies is that a large population of aquatic organisms, most of which are edible are contaminated by poisons. If it is an example of fish, the same will be taken to the market where you and I will buy for a meal at home. The poisonous chemical remains, though at low concentration accumulates little by little in our bodies until a time when they are become toxic enough to influence a bad health in our bodies. The impact may be observed over a long period.

 

Control and management of  pollutants

It is a responsible of every citizen to ensure safety of water ion our environment. Watersheds are one of the most vulnerable areas to pollution. These areas need to be protected at all cost with the reinforcement of by-laws and several pieces of legislation if possible. Locally, chiefs and village headmen need to organize several civic education campaigns towards pollution control and management and best chemical use.

 

Regulators, distributors and all stake holders in pesticides and agricultural chemicals should be cooperative enough with each other to ensure effective measures are being implemented. Registration of any new pesticides with the Pesticide control boards enables checks of admissible concentrations of the elements in the chemicals.

Some farmers who are used to buy chemicals in bulks eventually find themselves remaining with chemicals banned for use in the fields. They see it as a loss to discard these items and eventually, they still use the chemicals in their fields. This is one other area that needs to be checked. Extension workers can facilitate this work well as they are familiar with the type of people they are dealing with.

 

There is need to control use of some chemicals and to protect all vulnerable zones.

Chemically, though expensive, use of ion exchange resins can help to get rid of some salts that are harmful in water. Conversion of nitrogen salts to gas or bio nitrification is another way to use whilst getting advantage of living microbes life cycles.

Developing countries like Malawi can benefit a lot from abiding to agreements that were made at international levels on pollution management.

 

One of these is the Dubai convention that among other things ensures the role of the state in creating a healthy and well sustainable environment. Through such ways, countries will be able to achieve sound management of chemicals throughout their life cycle, minimizing significant adverse effects on the environment at large.

However, developing countries like ours essentially lack this capacity to ensure that everybody at every part of the country is following measures to manage pollution.

 

One other thing worth noting is the use of un labelled, expired and banned chemicals. It should be made sure by all stake holders that have knowledge of the chemicals they are using at a particular time. Some chemicals are sold at black markets with no details of their toxicity, concentration and properties. This can not spearhead the campaign towards a safe environment. These chemicals on the black market are usually cheap and many people flock to them.

 

Another point of concern to the health of our environment is damping. I appreciate that lack of proper structures for dumping in our townships is prevalent. In areas like kawale, Biwi, area 25, Bangwe and other river bank areas seem to have a great deal of problems hoe to manage wastes. It is very sad that some damping areas for the entire community are close to primary schools. Being well mindful that some wastes are toxic, it is a hazard to life to have landfills and dumping areas situated very close to schools and residential areas. I have used the term landfill in this case because the dumping areas are usually neglected for a very long time without being collected by the assembly until one time, a friend from mzuzu approached me that they had a similar problem and wanted to sue the assembly for risking their lives. Many persistent chemical derivatives from expired medicine, lotions, petroleum cans, ethylene and body wastes are all in the landfill heaps that we see.

 Disease causing pathogens are breeding themselves right there. it is terminating our own species if we are not to take care of our own environment.

Problems of this type are worse during rain seasons. It is best to make a team initiative in our communities to manage our environment. Let us learn to manage our water, and this will save us, save our animals and save our plants. The ecosystem will be flowing in a smooth chain of a healthy life. It all almost starts with water……..clean water, safe water, safe livelihood. Love your life, conserve your environment.

 

 

Acknowledgements

Report of the united Nations conference on Environmental and development, Rio de Janeiro, 3-14 June, 1992. United nations Publications

Report of the World summit on sustainable development, Johannesburg, south Africa. 26^th august-4^th September,2002. united Nations publications

Strategic approach to international chemicals management, 6^th June, 2006. secretariat for the strategic approach to international Chemicals management