A dangerous substance is any chemical, material, or compound classified as hazardous due to its potential to cause harm to human health or the environment. In UK property development, these may include asbestos, hydrocarbons, or industrial chemicals present on-site or in building materials. Their presence can affect planning approval, delay construction, and increase remediation costs. Developers and funders must consider dangerous substances during environmental assessments and comply with regulations such as the Control of Substances Hazardous to Health (COSHH) and the Environmental Protection Act. Lenders often require verification that no dangerous substances pose a financial or legal risk to the project.
Where dangerous substances are identified, developers will typically need specialist surveys, risk assessments and, in some cases, remediation strategies before progressing funding drawdowns or key construction milestones. The issue is particularly relevant within Planning and Environmental Law, as contamination risks can create liabilities that affect land value, project viability and lender security. Funders routinely review environmental reports to assess whether hazardous materials could result in enforcement action, unforeseen clean-up costs or delays to practical completion. In this context, dangerous substances are often considered alongside Environmental Licence requirements, especially where site activities involve regulated materials, emissions or waste management obligations.
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