Why is Dog Poop Dangerous?

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Dog Waste

Dog waste is classed as offensive waste in both the U.K. and E.U.


All faeces contains bacteria that can cause stomach upsets if ingested, however the greatest risk to public health from dog faeces is Toxocariasis.


Toxocariasis is an infection of the Roundworm, spread via unwashed vegetables and dog faeces. Young children are at particular risk due to their weaker immune systems and because they are more prone to ingest the eggs. A puppy can pass as many as 15,000 eggs per gram of faeces, and they are a major source of environmental contamination.


Each T. canis female can lay up to 700 eggs a day. These are passed out when the dog defecates and can survive for up to three years in soil. After two to three weeks of warm weather the eggs develop into an embryo state, containing larva - this is when they become infective to dogs and people. The larvae try to migrate through the human body as they would in a dog's, but the human body treats them as foreign material, which causes a reaction and tissue damage.


There are two types of Toxocariasis: visceral larva migrans (VLM) and ocular larva migrans (OLM).


In VLM, the larvae reach the liver, causing inflammation and symptoms such as abdominal pain and pyrexia. Most people recover spontaneously.


OLM occurs when a migrating larva reaches the eye. It causes a granuloma to form on the retina, causing significant visual impairment and in severe cases even blindness.


There are on average 12 new cases of OLM diagnosed each year in the UK.

Environmental Controls & Disposal Methods

It has been estimated that there are around 8 million dogs in the U.K. producing over 1,000 tonnes of faeces each day.


U.K., E.U. and local authority controls and directives are in place detailing how dog waste should be handled, transferred and disposed of. These controls cover: the dog owner’s requirement to pick up their dogs faeces in public places; that companies transferring the waste are licensed, transfer it in secure, sealed, offensive waste marked bags and that the waste is carried to a licensed disposal site as fast as possible. The transfer and disposal must be tracked from end to end through the use of Waste Transfer Notes (WTN) and auditable evidence retained that the WTN has accurately detailed the waste disposal stream.


We believe that all of these controls are adequate and necessary but that the final disposal method causes an environmental impact as the waste is normally disposed in landfill sites.  Every tonne of excrement locked underground produces 450 kg of greenhouse gases that are piped into the atmosphere.


There are however alternatives to landfill disposal.

Four alternative ways to treat dog waste

1. Anaerobic Digestion (AD)

2. Composting

3. AD followed by composting

4. Incineration


1. Anaerobic Digestion. In AD, bacteria decompose organic matter in the absence of oxygen. This anaerobic process produces methane and bio solids. The methane is a biofuel and used to generate electricity. The bio solids, like compost, can be used as a soil additive. The bacteria used in AD thrive at either 30-42 °C or 43-50 °C, referred to mesophilic or thermophilic digestion, respectively.


2. Composting. An aerobic method of decomposing organic matter. The process occurs at elevated temperatures and produces a nutrient rich soil additive. Though the temperature of composting depends on the volume of the organic matter and the system that is used, a minimum of 55 °C for three days is required for the product to be sold commercially as a fertilizer.


3. AD followed by composting. Using a combination of the two methods allows the production of bio-gas and also produces a smaller volume of soil additive without reducing the nutrient content.


4. Incineration. You might think that burning dog waste would create large scale air pollution, however that isn’t the case at all.  The technology within large scale incinerators is very efficient and produces little to no harmful emissions. The end product is still sent to landfill but the volume has been dramatically reduced.

Our preferred process

We would like to see AD and composting used much more in the U.K. to dispose of dog waste. As our company grows the volume of waste that we are dealing with will increase to a level where we hope to encourage our waste disposal partners to begin using these technologies as opposed to landfill.