How the EPA reached its position following years of research

A major research program to assess the benefits and risks of applying the material to land was commissioned by the NSW Government to inform the EPA position.

Scientific research has informed the position

A key component of the research program was a multi-year, independent research investigation conducted by the CSIRO, the Department of Primary Industries, University of Sydney, University of New England and the Office of Environment and Heritage. The research results have been peer-reviewed by local and international experts.

The EPA's position on MWOO has also been informed by Human Health and Ecological Risk Assessments that were in turn informed by new research undertaken by an expert panel overseen by the Office of the Chief Scientist and Engineer.

Could the EPA issue new controls to the industry?

The EPA’s responsibility is to protect the community and our environment. We are committed to engaging with the waste and recycling sector to increase resource recovery rates and encourage innovative, sustainable solutions that help to achieve this goal.

In order for the EPA to issue any resource recovery order and exemption, there must be evidence to support the practice is beneficial and will not cause harm to human health and the environment. 

However, the research shows

  • limited evidence of agricultural or soil benefits at existing application rates
  • human health and ecological risks at higher application rates 
  • lack of effective technology to reduce risk

Limited evidence of agricultural or soil benefits at existing application rates

The EPA’s overarching responsibility is to protect the community and our environment. 

The research undertaken including the assessment of human health and ecological risks and advice from scientific experts has been extensive.

The research clearly shows that the potential risks outweigh the limited benefits for application of MWOO on agricultural land, given the levels of contamination in the material from glass and plastics, as well as chemicals.

Human health and ecological risks 

As part of the research program the EPA commissioned a Human Health and Ecological Risk Assessment (HHERA) to better understand the potential risk of exposure to people on farms and the environment where MWOO had been applied in the past. 

The HHERA concluded that in most scenarios the exposure risk to the chemicals polybrominated diphenyl ethers (PBDEs) and from perfluoro octane sulfonate (PFOS), for people on farms where the material had been used was generally low and acceptable. 

An expert panel convened by NSW Health reviewed the research and has advised that it does not expect any health effects from past use of MWOO on agricultural land.

Lack of effective technology to reduce the risk

The EPA commissioned additional research to identify if technology was available to reliably remove known physical and chemical contaminants, including persistent contaminants such as glass, plastic and PBDEs. This work included consulting with AWT operators, as well as technology and equipment suppliers.

The research found that there is no commercially available technology to remove small contaminants, including glass, metal and rigid plastics less than 2mm and flexible or film plastics less than 5mm. Similarly, there is no technology available to specifically target chemical contaminants, such as PBDEs, PFOS, phthalates and heavy metals.

Without available technology, there is no evidence to suggest that AWT operators could meet any further restrictions that the EPA may require around the removal of persistent contaminants from MWOO. Therefore, the EPA does not intend to develop new resource recovery orders and exemptions to allow general land application of the material as a soil amendment.



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