John Mmbaga
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Circular economy: Wastewater redefined
We left the offices and started our short field tour. I thought that we would just take a walk but the terrain was challenging besides the possibility of encountering hippos in the…
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Recovery of crop nutrients from wastewater
It is possible that some of the vegetables we have eaten have been grown using wastewater. This does pose numerous problems such as exposure to toxic metals, bacteria and dissolved substances. However, this seems to be a practice that is rife especially in the low-class urban neighborhoods. Communities strained by unemployment and lack of basic […]
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Sewage and its potential as a drinking water source
Resources are all around us.But rarely do we think of water as a resource especially when considering wastewater. Yet for over 50 years, Veolia, a utility company has been converting wastewater into drinking water in Windhoek, Namibia. A tall order it would seem. However, come to think of it, water constitutes over 90% of wastewater. If […]
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Reclaiming polluted water: capacitive desalination
Treatment of effluents from industries before discharge into the environment is a subject of concern today because of the disease burden it creates. Among the pollutants of concern, metals and dissolved industrial chemicals are significant. Though several treatment strategies have been used before, efficiency of pollutant removal still has a long way to go. But […]
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Groundwater nitrate and why it should concern us
What do grazing cattle, usage of fertilizers and poor sanitation have in common? Well, these activities affect our drinking water in more ways than we could imagine. Groundwater This valuable resource of drinking water has hydrated us for ages. Though hardness might be an issue in a few places, groundwater has that epic taste that […]
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Our environment and the carcinogenic free-fall
The environment offers us opportunities to thrive. But careless human activities have adversely exposed us to threats that not only lead to environmental damage but to health complications. The rise in cancer cases especially among the urban poor in sub Saharan Africa may partly be attributed to improved diagnostics. However, careless environmental practices coupled with […]
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Emerging pollutants: Emerging threats
Ever asked yourself about the costs of technological progress? Among them, emerging pollutants are inconspicuous new kids on the dirty block bringing with them a new healthcare challenge. Emerging pollutants are byproducts of several pesticide, pharmaceutical and industrial chemicals increasingly polluting our environment. Though credible agencies such as the IARC have not conclusively categorized them […]
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Rice husks: Agro-waste useful in water treatment
Rice production releases tonnes of waste material called rice husks. Though different innovations on their usage have been tried, one promising application is in water filtration. But rice husks cannot be used as they are. They must first be amended to a form fit for water filter use. Rice husk ash Rice husks or hulls […]
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Water disinfection: looking beyond chlorine
Ever since the discovery of microscopic life, man has always been weary of bacteria in water. And rightfully so. Microorganisms in water are associated with a number of severe to deadly infections such as cholera, dysentry and typhoid. Since many water microrganisms succumb at a temperature of around 80 degrees celcius, boiling has been employed […]
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Toxic ‘river’ in the city
Rarely do you walk through an informal settlement (slum) and miss out a run off, a stream or even a river. Being mainly zones that are neglected by the ‘powers that be’ one would think that such water resources would be taken care of at least to allow the locals a free access to clean […]
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Water, the food chain and persistent pesticides
Though pesticides are meant to help manage pests and diseases, some linger in our environments long after use. Such is the case with a special class of pesticides called organochlorines. Organochlorines are chemicals adversely categorized by the UN Stockholm convention as persistent organic pollutants (POPs). These are chemicals which once released into the environment, are […]
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Water is life: A geological ‘raw deal’
The descent into Kenya’s Rift Valley is a scene to remember. The escarpment abruptly lets you into an open space with your eyes wandering tens if not hundreds of miles away through the plains with volcanoes protruding from them. Kenya’s Rift Valley is the country’s food basket inhabited by hardworking people. But sections of them […]
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Water is life: Acidic water
From the first day I tasted hot lemon water, I have always ensured that I take it religiously every evening before retiring to bed. Several things are appealing to me about it… Its bitter- sweet taste… Its citrusy texture… But above all, its acidic nature that corrodes our throats in a ‘friendly’ way… No wonder […]
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Water is life: The unease about race
The death of George Floyd in Minneapolis, Minessota precipitated a global movement with a life of it’s own. Before this event, Black Lives Matter was just an amorphous conglomeration of Black (and a few White, Native and Hispanic) activists agitating for justice for unarmed Black men killed by the police. With the brutal death of […]
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Water is life: The messy synthetic concoction
Arguably, no other type of pollutants create such a mess in our drinking water like synthetic stuff… Man-made chemicals used for different purposes but which somehow end up in our drinking water without our knowledge. Yes, some of these chemicals are useful in agriculture, medicine and even at home. However, the major problem with by-products […]
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Water is life: ‘Forever chemicals’
Rarely are nicknames used when describing serious pollutants in our water. But ‘forever chemicals’ attract a nickname for a couple of reasons: Firstly, they are so many in number (some estimates put them at around 5000 or so). It is therefore simpler to lump them together using an attribute they have in common: Their inability […]
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Water disinfection: the chlorine dilemma
Irresponsible human activity never leaves our environment the same. Though man-made, synthetic chemicals useful in industry, agriculture and medicine have made our lives better, they have adversely impacted on the quality of water we drink. Perhaps that’s why most of us are obsessed with treating our water using chlorine before drinking it. Chlorine is not […]
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Wastewater and the energy/agriculture nexus
Wastewater in many ways is not a waste but a resource. And the difference is how we choose to look at it. For the most part though a filthy sewage river is repulsive to the common person it holds answers to some of the most pressing problems we face daily. Energy Wastewater teems with bacteria […]
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Water is life: invading seawater
The mangrove tree is a wonder by any standards… Growing right along the shoreline, it creates a unique ecosystem for many shoreline sea creatures that thrive on the rise and fall of the tide. But besides it’s ecological significance, the mangrove tree uses seawater to grow… It’s special protruding roots absorb seawater while acting as […]
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Antibiotics in water: an emerging challenge
Indiscriminate use of antibiotics creates a major problem: bacterial resistance. So what’s that got to do with water? Growth of suburban neighborhoods in developing nations ends up concentrating many people within a limited space. Of course such a scenario has it’s advantages such as a ready market for consumer products. However due to lack of […]
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