Biosolids are what is left behind after sewage water is cleaned and treated. This substance is high in organic content and plant nutrients and supposedly makes an excellent fertilizer. Ontario for one has successfully regulated the application of sewage biosolids to land as a crop fertilizer since the early 1970's. Before application, the agricultural land has to be treated by an approved process and must be tested to determine if the nutrient content meets the provincial standards.
Some pros of using bisolids as fertilizer include that it reduces the need for commercial fertilizers, reduces production costs, improves the fertility of the soil, enhances the soil's moisture retention, permeability, and structure, and it adds organic matter that helps reduce the potential for soil runoff and runoff. There are also cons to this method, as claimed by the opponents. One of the main concerns is long-term buildup of heavy metals in the soil, it is argued that if some of the metals are built up to extremely high levels, they will damage the soils. Currently, it is not known as to what levels these metals become harmful.
Although, we may view biosolids and human waste as unsanitary and disgusting, there are many important things that must be kept in mind. If not applied and used as fertilizer, where would our waste go. Most likely if not used a fertilizer, human waste would have to be incinerated, sent to landfills, or even the ocean. These methods are all extremely bad for the environment, whereas using biosolids as a fertilizer is actually good for the environment. Something else to consider is wouldn't our waste just continue to build up if we don't find alternate uses?
There is no need to worried about whether or not this method is safe or not either. They have been used for years and no adverse effects to human health have been observed. Treatment plants are careful to make sure it is completely safe, and naturally-occurring soil organisms are able to destroy any pathogens that may remain within the waste. If you are just worried about the odour however, yes biosolids do smell, but they are preventative efforts for even that. Treatment targets the breakdown of organisms that cause potential for odour and agricultural fields that employ this method have to be at a minimum distance away from residential areas.
Just due to the fact that this method helps the environment greatly is a reason to support it. By having organic matter be recycled for centuries to improve soil productivity and fertility and by providing essential plant nutrients and improving soil structure there is little reason to not support biosolids being used as a fertilizer.
SOURCES
http://www.mindfully.org/Pesticide/Sewage-Sludge-Pros-Cons.htm
http://www.omafra.gov.on.ca/english/nm/nasm/sewbiobroch.htm
http://www.biotechag.com/faq.html
http://www.epa.gov/agriculture/tfer.html
COMMENTS
Angeli MartejaMonette Tam
