How Does Sewage Affect the Environment?

As much as we’d like to avoid it, sewage is an important consideration for every part of the world. What is it? Simply put, it’s water-carried waste. Whether it’s the stuff that leaves your toilet, or the vast amounts of wastewater that flow out of industrial plants – we all contribute to it and collectively we all have to deal with it. But what exactly is ‘dealing’ with sewage? And what is the impact of sewage on the environment?

Sewage and wastewater

Unfortunately, the effects of sewage on the environment are largely negative. It needs to be properly treated before it can be disposed of – usually into the ocean. There are two problems, however. If sewage is only partially treated before it is disposed of, it can contaminate water and harm huge amounts of wildlife.

Alternatively, leaking or flooding can cause completely untreated sewage to enter rivers and other water sources, causing them to become polluted. The consequences aren’t great. In September, a large part of the River Trent was polluted by sewage in Staffordshire. Over 15,000 fish were killed, and it would have been worse if the sewage had reached a human water source. Contamination of water sources can cause diseases to spread, such as e-coli, diarrhea and hepatitis A.

Even properly treated sewage can have its problems. Researchers have recently found that microscopic plastic fibres, released when certain clothes are washed, can make it through wastewater treatment plants and into marine ecology systems. Like the more common contaminants, they can harm animals and damage the food chain.

Utilising sewage

It isn’t all bad though. As well as pollutants, human sewage contains a pool of information that can be used to monitor a range of areas. While most research has focussed on monitoring the use of illegal drugs, it is now being extended to the other potential fields of research. Determining the presence of pesticide metabolites, for instance, can be beneficial for the food and agricultural sector.

Analysing wastewater can also detect markers of oxidative stress in collective samples. This is essentially an indication that bodies are unable to neutralise certain diseases. It can help researchers determine the effects of environmental pollution on particular communities.

But how does it work? Because wastewater is so diverse and complex, targeted analysis requires more advanced methods. ‘The utility of municipal wastewater analysis for drug epidemiology, food safety and environmental monitoring: From targeted analysis of biomarkers to non-target screening’ is an eLearning course which explores the world of wastewater-based epidemiology. It looks at the different analytical techniques and technology required for analyses, but also where the field is heading with current and future developments.