Experience & Research

The use of biosolids on family farms and forests in Virginia depends on scientific scrutiny from reputable research institutions.  Biosolids in all forms – Class A, Class B, composted or blended material – continues to be thoroughly evaluated in research studies by academic institutions across the country.  In fact, the study of biosolids and its environmental and health risks has been the focus of hundreds of university research studies conducted for many years. The results of this extensive research show that biosolids can be safely applied to farmland without harm to the environment or to human and animal health when applied according to the regulations.

In Virginia, HRSD’s Progress Farm in Virginia Beach has been at the forefront of biosolids research. For more than 30 years, HRSD has been cooperating with Virginia Tech scientists to research the environmental safety of biosolids. Since beginning its research at the Progress Farm, neither HRSD nor Virginia Tech has identified any public health, environmental or safety issues resulting from repeated application of biosolids on HRSD’s Progress Farm.

Contained below is information about some other research activity:

  • Virginia and EPA regulations require site management procedures that prevent the transfer of any remaining pathogens that may be found in Class B products to humans or the environment at levels of concern. Class A Exceptional Quality (EQ) biosolids and products are also being land applied in Virginia. These biosolids and products are pathogen free and provide further protection of the environment.
  • Other biological concerns associated with land application of biosolids include antibiotic resistant bacteria, prions and aerosolized endotoxin. The presence of antibiotics and antibiotic resistant bacteria in biosolids is well documented, but risks from antibiotic resistant bacteria in soil amended with residuals are thought to be low (Diversity of aerosolized bacteria during land application of biosolids, Brooks et al., 2007). It is important to note that soils are the original source of natural antibiotics and that all soils contain antibiotic-resistant bacteria. A report performed by the U.S. Geological Survey (23) summarizes the analysis of thousands of soil samples collected across the United States.
  • There are research studies on some Pharmaceuticals and Personal Care Products (PPCP’s) that indicate little cause for concern, but some scientists continue to question the use of biosolids due to a “what if” factor. There is ongoing research in this area, and no findings to date have prompted the need for additional regulatory action.
  • Risks from polybrominated diphenyl ethers (PBDEs) and estrogenic compounds contained within land applied biosolids were recently evaluated (Fate of Endocrine Disruptors Following Long-Term Land Application of Class B Biosolids and Risks to Public Health, Quanrud et al., 2010) and found to be low. Instead, the primary risks to human health associated with these compounds are related to direct household exposure from dust. Concentrations of PBDEs, for example, are much greater in household dust than in municipal biosolids (Polychlorinated naphthalenes in human adipose tissue from New York, Johnson-Restrepo & Kannan, 2009). While endocrine exposure is one area where more research is needed, it is not evident that land application of biosolids is a major source of such exposure.
  • Scientists continue assessing biosolids risk today, as evidenced by the active work of the W3170, a multi-state workgroup composed of representatives of the EPA, the U.S. Department of Agriculture, universities, and municipal governments from across the U.S. conducting research to better understand any potential hazards as well as the value/benefits of constituents found in biosolids and other residuals.Additionally, under the Clean Water Act, Section 405(d)(2)(C), the EPA is required to conduct a review of the 40 CFR Part 503 standards for biosolids use not less than every two years for purposes of regulating new pollutants where sufficient data exist.

Biosolids will always bring with it some challenges; however it is imperative that strong scientific evidence continue to be the foundation for the beneficial use of biosolids. To this point, despite the continuing dialogue expressing concern regarding the ‘state of the science”, current science continues to support the beneficial use of biosolids in agriculture, forestland, and even home gardening where EQ biosolids are permitted