Phytotoxic Assessment Q & A

18th January 2020

Soil quality and sustaining plant growth go hand-in-hand. But few may have heard of a phytotoxic assessment and what impact this may have on your garden, allotment or proposed development. By way of an introduction, Northpoint provide a brief and informative Q & A.


What is Phytotoxicity and a Phytotoxic Assessment?

Phytotoxicity is the toxic affect a soil might have on sustaining the healthy growth of a plant, tree or shrub. A phytotoxic assessment involves analysing your soil to determine whether elevated contaminants are present, and are potentially causing harm to your soft landscaped areas. 

Where in Britain can Phytotoxic soils be found?phytotoxic assessment

Quite simply, almost everywhere! Northpoint has assessed numerous brownfield and greenfield sites all containing raised phytotoxic compounds.

What are the causes?

They can either be naturally derived from a soils parent material or result from historical site uses. Every soil has a mixture of minerals, organic and inorganic compounds. Typically, soils containing a high concentration of minerals such as copper, zinc and nickel may be characterised as phytotoxic.

How do I established if my soil is contaminated?

Northpoint routinely undertake phytotoxic assessments. We rely on undertaking a site-specific soil survey. The survey will involve us characterising your target soil horizon in accordance with guidelines set out in various British Standards. We will sample the soil material and subject this to laboratory analysis. The analysis informs our assessment to establish if you have a problem.

Are there any requirements to undertake an assessment?

Not always, but more often Local Planning Authorities may request that a phytotoxic assessment is undertaken within a wider soil or ground investigation.

Where can I get more information?

British Standard BS16729 “Soil Quality” provides guidance on what levels of mineral concentrations in your soil are acceptable. Alternatively, you can get further information from contacting our Geoenvironmental Engineering Team. We can talk you through the technical process.


Should you have a general interest in soil quality, or any specific concerns regarding the soil at your home or proposed development, the team at Northpoint would like to hear from you.
Email: info@northpointgeotechnical.com
Tel: 0191 917 2310