Part B - Evidence Base

Strategic Environmental Assessment (SEA) provides an important opportunity to enhance health outcomes by influencing the wider determinants of health.

Purpose of the Guidance on Health

This revised guidance ^[1] on health in SEA aims to support compliance with the ‘human health’ requirements of the SEA Directive. This guidance is relevant to SEAs of plans or programmes that cover England, or England plus any other part of the UK and comes in three parts:

• PART A: The target audience is SEA practitioners and Responsible Authorities (RA) preparing SEA scoping and environmental reports.
• PART B (this document): The evidence base provides a technical resource for SEA practitioners and RAs including an evidence base on causal links between human health and environmental changes.
• PART C: Provides guidance for health professionals and bodies supporting the SEA process.

Links with Sustainability Appraisal and Appraisal of Sustainability

Sustainability Appraisal (SA) and Appraisal of Sustainability (AoS) cover economic and social impacts and incorporate the requirements of the SEA Directive. This guidance is therefore also applicable to the assessment of human health effects in SA and AoS.

This guidance should be read in conjunction with the Communities and Local Government publication A Practical Guide to the Strategic Environmental Assessment Directive

Evidence Base of Causal Relationships between Human Health and the Environment

Climate Change

• /Heat waves are associated with increased mortality rate, particularly amongst vulnerable groups and in cities, and increased levels of hospital admissions.
• Cold spells are associated with increased levels of hospital admissions, as well as deaths.
• Fuel poverty is associated with increased cold weather deaths for those on low incomes.
• Increased warmer conditions are associated with increased pathogen growth and may also extend the range of both new pathogens and new vectors (animals carrying diseases) into the UK. The risk that climate change will result in significant increases in national or regional disease burden is low, although there may be some local level effects.
• The increase in the number of sunny days will increase ultraviolet radiation exposure, which causes eye cataracts and skin cancers. Sunlight exposure has some health benefits, including increasing production of Vitamin D and reducing Seasonal Affective Disorder (SAD).
• Flooding in the UK is mainly associated with a reduction in mental health and long-term physical health effects, rather than direct injuries from flood events or large scale infections directly following flooding.
• Reduced healthy food availability is associated with rising food production costs and adverse weather conditions in global regions from which food is imported.
• High winds are associated with an increase in deaths, mainly associated with vehicles.
• More frequent extreme rainfall events are associated with increased surface water turbidity and higher numbers of indicator bacteria and pathogens in surface water.
• Winter air pollution episodes are associated with respiratory conditions. However winter air pollution episodes are already low and are expected to decrease further; related health impacts are therefore also likely to decrease.
• Summer air pollution episodes are associated with respiratory conditions. Summer air pollution episodes will increase in frequency and intensity as the associated weather conditions also increase in frequency and intensity due to climate change.
• Climate change mitigation to change transport modes in cities is associated with not only a reduction in greenhouse gases, but also a reduction in air pollutants harmful to health and an increase in levels of physical activity.
• Switching to low carbon energy generation is associated with health benefits.
• Short lived greenhouse pollutants (sulphates, black carbon and ozone) are associated with adverse health effects, particularly in combination with each other and other products of combustion. The complexity of these health effects needs to be recognised in mitigation policies.

Footnotes