In January 2020, the Queensland Government released version 2.0 of the End of Waste (EOW) code for biosolids.  The code requires monitoring of PFAS and Total Organic Fluorine in the raw biosolid resource, without specific trigger values. The soil to be used for amendment is to be screened using standard PFAS analysis and TOP Assay. The code then requires calculation of expected concentrations of the soil amended with the biosolid resource in consideration of PFAS concentrations determined in the biosolid.  It then sets specific trigger values for PFAS in the amended soil analysed after application and within 3 months of application occurring. The code requires all analysis “be carried out by a laboratory that has NATA certification, or an equivalent certification, for such analyses” (clause 6.14).

Summary of ALS NATA Accredited Testing Services for Biosolids

* Refer to Table 1 for specific LORs offered for individual PFAS analytes

Sampling & Analysis

The standard HDPE specimen jar for soils is also applicable for sampling biosolids. Samples should be submitted to the laboratory chilled. It is important to clearly mark the samples as biosolids on the chain-of-custody to ensure safe handling by the laboratory.  

The high organic content of biosolids present unique analytical challenges for PFAS beyond standard soil matrices.  Extraction efficiency is typically poor for conventional solvent extraction techniques used for soils, resulting in low PFAS recoveries. In addition, co-extracted organics impart significant analytical interferences.  ALS has developed a unique QuEChERS extraction procedure to maximise PFAS recovery from biosolids, including a comprehensive extract clean-up to remove interfering co-extracted organics.  QuEChERS is a well-established technique for the extraction of pesticides from complex biological matrices and lends itself well to fluorinated organics such as PFAS.