Lab to test for pathogens in biochar charged with human urine? #urine #analysis #pathogen

Kobus Venter

Hi Kevin,

I assisted IMPILO YABANTU in developing a low-tech system (fully franchised will come out under $60k US) that can dry and carbonize faecal sludge, which over a period of 3 years (since 2017) morphed into 6 interconnected kilns (containing drum retorts) in a process we coined 'progressive batch' where gases flow from one kiln to the next in series. Some of it was funded by the Bill & Melinda Gates Foundation. 

So my experience only relates to sterilizing faecal sludge, in which some lab samples contained up 400,000 coliform concentrations down to Nil. Our "biochar" product is sold to Regenerative Agriculture Specialisation (RA$) in South Africa. At this stage we see no use of placing coliforms back into the biochar we have spent considreable energy removing. They have already done extensive field trials with a product that contains biochar. Their product called VitaSoil has 4 components:

1. Biochar which provides the refuge for microbes

2. Decomposed pine sawdust - nutrient source

3. Vermicasts - diversity 

4. Selected microbes with increased tolerance to chemicals and heat to help re-ignite soil biology

The natural "soil reef" created by above amendment will assist the natural microbes in the soil to flourish. 

I would also point you to Green Peace efforts to counter the practice of dumping contaminated sewage on fields in the UK:

The problem as I see it is that humans and animals that step onto these pathogens can spread it into households unintentionally.



On Sat, 10 Oct 2020, 22:12 mikethewormguy via, <> wrote:

I would test the urine before applying it to the char

I would recommend creating a lot system for the urine collection for the purpose of traceability. The volume of the lot is based on risk management and not on science.  It is a business decision.

Each lot should be tested and the lot test data provided to the grower.

The pathogens we test for include generic Ecoli, Salmonella,  fecal coliform, and shigella toxin. Here in the US these test take around 5 days to get done and cost around $100 total.

You may want to consider a "kill" step using either dropping the pH or adding an essential oil.  The kill step provides assurance that no matter what happens upstream, the material applied to the crop is pathogen free at the time of delivery.

In addition, are you familiar with HACCP....?  Hazard Analysis Crtical Control Points is a food safety approach that maps all of the steps in a process where a contaminant, physical, biological, chemical, can enter the process. 

Food Safety is all about risk management. Lot control is all about limiting the size of your risk.

my 3 cents 

Mike, a Food Safety/ HACCP auditor in a prior life.......

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