Biosolids is a term used for sewage sludge that’s been treated to be used as fertilizer. The question is, is this a good idea. At first glance, it seems like this would be a good idea, since biosolids are rich in plant nutrients and organic content; it’ll be like manure being used as compost. And this is the same idea they were going along with. Utilizing the biosolids, instead of simply disposing of them in landfills or incinerating them, like usual, will help reduce the size of landfills and be more cost-effective than just incinerating it.
What we do have to take in consideration though, is the side-effects and possible risks this procedure brings. What will it do to the soil and crops? What kind of problems may arise with using human waste? Is it possible for the biosolids to be more harmful than it would be helpful to the environment? These are the kind of questions we have to ask scientists and other specialist before biosolids can be used in this manner.
There are many pros and cons relating to this topic, and both sides have very good information to sustain their arguments. The up side of using biosolids as fertilizer is that, as stated earlier, they will not end up rotting away uselessly in a landfill or using up money for incinerating, and are enriched with organic materials which are essential for plant growth. The downside of using biosolids is that there is a risk of heavy metal contaminants that could seriously harm the development of crops and other plant life. There is a risk of contamination when near civilization. Then there is also an odour factor due to the ammonia and sulfur components that are found in the biosolids.
There are two different categories of biosolids that are made; Class A biosolids and Class B biosolids. Class A is the highest quality of biosolids where pathogens and heavy metals are significantly low, and is safe for human exposure. While class B is of lower quality and has a higher heavy metal and pathogen concentration. Class B biosolids are used on crops that aren’t consumed by people, such as hay and grass crops. Class A is clearly the type of biosolid that is to be used on consumer crops. Unfortunately this isn’t always the case.
In truth, this application of biosolids is already being used in some parts of Ontario; of course with certain boundaries and rules on how and where it’s used. But luckily for us, the quality of sewage treatment plants in Ontario is fairly high meaning we don’t have to worry too much about the substance and risk of biosolids being used in Ontario, albeit the use of it is constrained to certain places and certain amounts.
But not all sewage treatment plants allow for completely safe use of biosolids; especially in places where the risk of heavy metal contamination is not acknowledged or taken into consideration. Places like the U.S. The States has the most relaxed set of standards for heavy metal contamination; a serious health risk for them. The heavy metals found within poorly treated biosolids can extensively damage crops and the soil.
What do I think about using biosolids this way? I think they would make a good fertilizer for the plants and would be more helpful to the environment and the economy to be utilized in this way instead of just wasting money incinerating it or filling landfills with it. That is of course, if high quality biosolids are used and if proper procedure and precautions for the application of biosolids is used. If not then no, risking contamination and possible heavy metal or any other kind of poisoning from biosolids is not worth using it.
