One of the findings from the results section of my thesis was about emerging contaminants of concern in wastewater treatment plants. Things such as pharmaceuticals, personal care products (deodorant, soap, shampoo, perfume etc.) and illicit drugs are starting to be studied and worry many public health experts. After we use these products, we flush them down the toilet, down our sinks and even our bathtubs. Then they travel to wastewater treatment plants which presently (in Canada) do not have the technology/capacity to treat these products. The person I interviewed explained how more research is required on this topic along with good public education to inform the public about which products are harmful to our water supply.
This is a major concern but lots of innovative research is underway. A group of four Chemical Engineering students from Ryerson University have discovered a potential solution to the rising levels of pharmaceuticals ending up in the water supply. Hospitals and long-term care facilities are increasingly using more pharmaceuticals and we still do not completely understand their effects on our water systems. The group from Ryerson designed an advanced wastewater treatment system which would “remove 90 per cent of pharmaceuticals and endocrine-disrupting compounds (EDCs) using commercially available technology”.
Why is this even a concern? In Canada, the government doesn’t enforce the removal of pharmaceutical drugs and EDCs, including Bisphenol A, from wastewater. As a result, municipalities don’t currently pursue removal, since it would cost a lot of money. However, if municipalities were to invest in systems that could treat and remove such chemicals, there could be significant savings in health care costs. Eventually, those chemicals enter the environment and the drinking water supply which could have so many negative effects on human health and biological function.
While there haven’t been any studies done to determine the long-term effects of these pharmaceuticals and EDCs on humans, concerns have nevertheless been raised. For example, some studies have "found that pharmaceuticals and EDCs have been implicated in such conditions as polycystic ovarian syndrome and hypospadias (a birth defect involving the male urethra)".
Without going into too much engineering technicalities (because I don’t completely understand every detail myself, here is how the group’s system works:
“The students’ proposed innovative design uses two processes in combination, both using commercially available technology. First, wastewater is subjected to membrane biological reactors. This activity increases the amount of bacteria already present in the treatment process and makes them “hungrier.” From there, sewage goes through an advanced oxidization process. Typically used to treat drinking water, this process works in the same way as an antioxidant does in the body: it destroys harmful toxins. But whereas most wastewater treatment plants use chlorine as a disinfectant the students proposed using ultraviolet light (UV) and hydrogen peroxide for the purposes of advanced oxidation and disinfection. Normally, UV light would be unable to penetrate murky wastewater, but after undergoing the membrane biological reactor, liquid waste in the students’ simulated wastewater treatment plants would be clear enough to permit the use of UV light. Afterwards, the students concluded, the wastewater would be clean enough to go straight into lakes and rivers”.
Key message: To see this kind of innovative research from undergrad students is incredible. As more research is being done on this critical topic, it is equally important to look at public education. Cities could use this opportunity to put together a list of pharmaceutical and personal care products that have negative effects on urban waterways. This list can take the form of a pamphlet or guide which can be distributed to the public. This is simply a precautionary measure but would go far in terms of raising awareness and education.
***The group’s project, Treating Pharmaceuticals and Endocrine Disruptors at the Source: An Advanced Wastewater Treatment Plant Design, placed 1st for Social Awareness and received an honourable mention for their innovative design of an advanced wastewater treatment plant at the 2010 Ontario Engineering Competition in Waterloo, Ontario***
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