So Bec has finally succeeded in getting me to sit down and write a long overdue article for you all, I think I am still traumatised after writing up my PhD thesis last year. Basically I have spent the last five lovely (but intense) years in Devon England, researching chemical pollutants and their effects on fish. And while my research questions were extremely niche, I’m pretty passionate about pollution in general and how we as individuals can make small changes in our daily lives to reduce the impact we have on our planet. I thought for my first blog post I would give a very short introduction to the very complex topic of environmental pollution and then delve a little deeper into the area of chemical pollution (my comfort zone).
What are pollutants?
Most people when they think of pollution will think of oil slicks covering large areas of oceans, plastic bottles littering shorelines or smog filled cities. And although these are good examples, it’s important to emphasise that not all pollution is visible to the naked eye. Pollution is in fact the introduction of any substance into the environment that would not be there in normal circumstances. This includes substances of various forms such as chemical, physical and radioactive pollutants. As you can see from the schematic figure, there are also some very specific types of pollution which might be a bit more obscure to the average person going about their business and they don’t often receive as much attention in the media. For example, noise pollution results from various activities such as underwater drilling on oil rigs, boat engines, cars, planes etc. Light pollution is a result of the use of artificial light in shops, homes, factories and street lights, whilst thermal pollution occurs mainly when water is used as a coolant in power plants and industrial facilities and then returned to the natural environment.
The various forms of pollution can effect multiple environmental compartments such as the soils we grow our food in, the water bodies (fresh, estuarine and marine) we drink from/bathe in and the air we breathe.
Air pollution.
Outdoor air pollution occurs as a result of the burning of fossil fuels (oil, natural gas and coal) to create energy and power, exhausts from motor vehicles and from factories, power plants, refuse incinerators, construction activities, fires and natural wind-blown dust. Indoor air pollution occurs as a result of cleaning products, paints and flame retardants. Air pollutants can be in the form of gases such as nitrogen oxides, sulphur dioxide, carbon dioxide, hydrogen sulphides, carbon monoxide, ammonia, ozone, hydrogen cyanides or they can be in the form of particulate matter composed of metals, organic compounds, material of biological origin and ions and reactive gases.
Land and soil pollution.
This is the product of poor agricultural practices, improper solid waste management, including unsafe storage of obsolete stockpiles of hazardous chemicals and nuclear waste, and a wide range of industrial, military and extractive activities. Leachates from mismanaged landfill sites and uncontrolled dumping of waste from households, industrial plants and mine tailing can contain heavy metals such as mercury and arsenic, trace metals, organic compounds and pharmaceuticals, including antibiotics and endocrine disrupting chemicals.
Freshwater pollution
Freshwater pollution, affecting our lakes, rivers, streams and groundwater, can result from heavy metals from mining activities, synthetic chemicals such as pesticides, paints and pharmaceutical as well as biological waste in the form of human waste and animal excrement. Polluted freshwater can go on to contaminate soils, coastal waters, oceans and land.
Marine and coastal pollution
Over 80% of marine pollution comes from land-based activities, either through deliberate dumping or from run-off through drains and rivers while marine shipping, fishing and extracting activities are other major sources. Both sources result in litter, debris, oil, heavy metals and radioactive waste entering the marine environment.
The effects of pollution on human health and the natural environmental are serious, complex and widespread. In terms of human health, there are some staggering facts out there. For example, 90% of child deaths from diarrhoeal diseases are directly linked to a lack of access to clean water and sanitation, 6.5 million people die annually as a result of poor air quality and over 100,000 people die annually from asbestos related cancers. Pollution not only has a negative effect on our health, well-being and livelihoods but also threatens the cultural, spiritual and aesthetic values that many people attach to the richness and diversity of the world around us. And of course we can’t be completely self-involved here. As a result of pollution, the biodiversity of plants and animals around us is under threat like never before. Over 80% of the worlds wastewater is released into the environment without treatment, there are over 500 “dead zone” in the seas where there is too little oxygen to support marine life and approximately 8 million metric tonnes of plastic enters the oceans every year. If that is not enough (all very gloomy, apologies), pollution has drastically altered the geophysical-chemical systems and process of the earth itself with global warming, ozone depletion and rising sea levels all direct results of human pollution.
Needless to say pollution is a huge challenge and it threatens to intensify as a result of our increasing consumption, our throw-away culture, rising living standards and population growth. And while at times all of this can seem a bit disheartening, I am quietly confident that we are moving in the right direction (very slowly). Following the release of BBC’s Blue Planet II late last year, there has been a huge wave of enthusiasm and support for protecting the environment against the growing threat of plastic pollution. It really has demonstrated that people are not only willing to make adjustments to their own daily routines, but they are also demanding action from local and national representatives. The general public and environmental charities have played a huge role in bringing about a number of monumental changes recently, for example the introduction of a bottle deposit scheme in the UK, the removal of plastic straws from all Wetherspoon’s pubs and the switch from plastic to paper cotton ear buds by Johnson & Johnson to name just a few.
I suppose the point I am trying to make is that we can make a difference BUT I firmly believe that access to the right information is crucial. How are we supposed to stop the problem if we don’t know what the problem is, right? The internet is full of information, some of it good, a lot of it bad. I hope that through series of articles on here over the next few months I can highlight some interesting facts around the area of pollution while also providing first hand source information (i.e. the peer reviewed scientific journal articles and/or legitimate websites) and point you in the direction of some useful further reading on the subject.
Aoife.
References and further reading (for the super keen):
Reports
https://www.epa.gov/ozone-layer-protection/health-and-environmental-effects-ozone-layer-depletion
Pollution and Human Health
http://www.euro.who.int/__data/assets/pdf_file/0003/194133/RB-Asbestos-Mtg-Report-Bonn-2012.pdf
http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.465.5144&rep=rep1&type=pdfhttps://www.researchgate.net/profile/Bernhard_Wehrli/publication/228264639_Global_Water_Pollution_and_Human_Health/links/09e4150eab3c546945000000.pdf
https://www.sciencedirect.com/science/article/pii/S0045653599001150
https://www.epa.gov/ozone-layer-protection/health-and-environmental-effects-ozone-layer-depletion
https://www.unicef.org/media/media_68359.html
Climate Change
https://onlinelibrary.wiley.com/doi/full/10.1111/gcb.12754
http://advances.sciencemag.org/content/4/4/eaap9741
Eutrophication/Hypoxia
http://www.int-res.com/articles/meps2002/238/m238p249.pdf
http://www.pnas.org/content/pnas/114/14/3660.full.pdf
https://pdfs.semanticscholar.org/3877/a0461fcbc2d9a5ca10222aa482f557ad8f4d.pdf