LQM is a specialist environmental consultancy based in Nottingham (UK) with an international reputation for assessing and managing the risks posed to human health and the environment by contaminants in soil. Increasingly this is being done within a context of sustainable development and specifically sustainable brownfield regeneration.

We provide consultancy, peer review and expert witness services, contract research and training courses on all aspects of the management of land contamination to problem holders, developers and local government.

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PAH Profiling Tool (Full version)

Only £50 (excl VAT) with online card payment discount.

Quickly and robustly determine if the PAH profile in soil samples deviates from that of coal tar and so determine whether a "surrogate marker approach" is applicable to the risk assessment of the PAH mixtures at the site.  For more details read on or click here to see a short video.

A free trial version of the tool is available but has limited functionality (you will need to register).  This full version offers a number of distinct benefits over the trial version, including:

  • The ability to identify which samples deviate from the range recommended by the HPA.
  • The removal of the watermarks and LQM branding (but not copyright statement) from the two charts. Also included in the price, we will insert your company logo into the two charts to create professional branded charts to include in your reports.

Note: Use of the software represents acceptance of the Licence Agreement, which is also contained within the software.  Please review the Licence Agreement prior to use. For organisations with multiple offices, a seperate copy of the software is required for each office. 

Prices and Discounts:

  1. Prices exclude VAT.
  2. Card payment only - 20% discount automatically applied.  Invoice purchases will be declined.
  3. Quantity discount: 25% off for 5 or more

Terms and Conditions apply


  • Content
  • Citation

PHE (2017) recommended the use of benzo[a]pyrene (BaP) as a surrogate marker approach in the assessment of carcinogenic risks posed by PAHs in soils and several generic assessment criteria have been derived based on this approach.  However, this approach is only applicable if the PAH profile in the soils is sufficiently similar to that of coal tar (see Background section below). Does your site data support the use of a surrogate marker approach?

The LQM PAH Profiling Tool is a simple to use spreadsheet (Note: Microsoft Excel is required to use the tool) that calculates the relative proportions of the eight genotoxic PAHs and plots them on the two charts relative to composition of the the two coal mixtures used by Culp et al. (the plus/minus an order of magnitude limits suggested by PHE, formerly the HPA).  Simply paste in your PAH site data (EPA 16) to evaluate the suitability of the surrogate marker approach and identify which samples, if any, deviate significantly from coal tar.  These samples should be investigated further to determine the reason for such apparent differences in composition. For example, they represent poorly transcribed data, issues to do with detection limits or laboratory anomalies. Alternatively, do they may indicate the presence of discrete hotspots or the presence of more than one source of PAHs at the Site.

If you want to know more, watch an hour-long recording of a webinar on PAHs, the surrogate marker approach and the PAH profiling tool - click here.

Purchasing and supplying your company logo

The price includes personalisation of the tool with your company name or logo.  Once the order has been received we will contact you (at the email address given in the account from which the order originated) with instructions on how to supply a suitable image file. We will replace the LQM logo (but not the copyright statement) on both charts with the image file you provide.

Once payment has been received the personalised tool will be delivered by email to the address given in the account from which the order originated.


Polyaromatic Hydrocarbon (PAH) mixtures are commonly encountered in urban and periurban soils. These PAHs can be associated with a diverse range of contaminative sources, including petroleum spillages, disposal of ash and clinker etc., atmospheric deposition of smoke and soot, gas works wastes, coal storage and dusts, and tarmac etc.

PHE (2017) recommended the use of benzo[a]pyrene (BaP) as a surrogate marker approach in the assessment of carcinogenic risks posed by PAHs in soils. It was recommended that such assessments should be based on toxicological benchmarks derived from the data for 2 coal tar mixtures presented by Culp et al. (1998).

This surrogate marker approach has the potential to substantially simplify the risk assessment of PAH mixtures in soil. However, PHE (2017) caution that this approach is only applicable if the mixture of (genotoxic) PAHs in the soil is sufficiently similar to that of the coal tar mixtures used as the basis for the toxicological benchmarks used in the assessment. PHE (2017) presented a graphical analysis method that compared the proportions of eight genotoxic PAHs within soil samples (as ratios relative to BaP) with those in the two coal tars tested by Culp et al. (1998). They cited the International Programme on Chemical Safety (IPCS, 1998) as concluding that “the PAH profile of a tested mixture may deviate from the average profile by about an order of magnitude (up or down)” and adopted this criteria for indicating whether soil PAH mixtures are sufficiently similar to the Culp et al. coal tars, and thus BaP can be considered a suitable surrogate marker.

Two generic assessment criteria have currently been published for BaP as a surrogate marker; a C4SL (Defra 2014) and a S4UL (Nathanail et al. 2015). However, before these assessment criteria (or any other criteria based on the Culp et al. coal tars) can justifiably be used to assess PAH mixtures in soils, the PAH profile in the soil should be assessed and shown to be sufficiently similar to the coal tars tested by Culp et al. (1998).

This spreadsheet facilitates a graphical comparison of PAHs in soil samples with that of the Culp et al coal tars, similar to that presented by the PHE (2017). This can provide a basis for a competent risk assessor to determine whether an assessment based on BaP as a surrogate marker is appropriate to all, or some, of the samples from the site.

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