Infectious substances and agriculture

What are the sources of infectious substances from agriculture?

Infectious substances can be found in farm animal waste and offal on farms. Contamination of freshwater may occur when the faeces of grazing animals are deposited near or in a waterway. This may happen when a cow crosses a stream, or when cattle and sheep graze unfenced waterways in pasture. Pathogens may also be washed into waterways indirectly through surface runoff from the land, especially after periods of heavy rain.

Potential impacts of infectious substances on water quality and mahinga kai

  • Decreased water quality.
  • Contaminated water and mahinga kai, especially shellfish, downstream of the discharge (source) that makes it unsuitable for harvesting (fishing or food gathering).
  • Water becomes unsuitable for swimming or recreational use.
  • Greater probability of disease-related impacts on fish populations.

Learn more about infectious substances in waterways and the potential environmental impacts.