Published: 10 February 2025
Public Health Wales is continuing to evaluate air quality data, to improve our understanding of the potential for harm to health of people living around Withyhedge landfill site. This air quality monitoring began in the spring of 2024, after Natural Resources Wales received large numbers of complaints from members of the public about smells linked to the site.
Our most recent health risk assessment is based on data from a number of sources and time periods. Data collected at the Spittal School monitoring station between 4th November 2024 and 26th January 2025 showed eight occasions when hydrogen sulphide concentrations in the air were above the 30-minute World Health Organization (WHO) odour annoyance guideline value (5ppb / 7ug/m3).
We have also reviewed air quality monitoring reports (8, 9 and 10) by Geotechnology at other sites in the community between 17th September and 3rd December 2024. These monitoring data have not recorded any occasions when hydrogen sulphide concentrations in the air were above the WHO odour annoyance (5ppb / 7ug/m3) level. Air monitoring undertaken by Geotechnology using diffusion tubes has not identified levels of hydrogen sulphide above longer term guideline (1ppb – based on a lifetime exposure).
These data indicate that the long-term (lifetime) health risk remains low. However in the short term we understand that bad smells in your community can be upsetting and even at very low concentrations, can lead to headaches, nausea, dizziness, watery eyes, stuffy nose, irritated throat, cough or wheeze, sleep problems and stress. This can happen even when the substances that cause the smell are not directly harmful to health. These are common reactions, and these effects should usually pass once the smell has gone.
Closing windows and doors when smells occur can help to stop them coming inside homes. Remember not to block windows or vents completely. This is because they provide air to vent cookers or heaters and can help to control damp. Once an outdoor smell has passed, opening windows and doors will help get rid of any smells that remain.
Multi-agency partners review and check monitoring data together. Public Health Wales then use it to inform a health risk assessment before sharing our conclusions with the public. The health risk assessment will continue to be reviewed and updated as more monitoring data is made available to us.
We recognise the real stress and anxiety that local people are under as a result of these smells. However, Public Health Wales does not have regulatory responsibilities or powers around the management or enforcement of a site, including carrying out monitoring. We can advise regulators, the public and other partners, and contribute to public health risk assessments.
Published: 15 November 2024
Public Health Wales is continuing to evaluate air quality data, to improve our understanding of the potential for harm to health of people living around Withyhedge landfill site. This air quality monitoring began earlier this year, after Natural Resources Wales received large numbers of complaints from members of the public about smells linked to the site.
Our most recent health risk assessment relates to air quality data collected at the Spittal School monitoring station between 1st October and 3rd November 2024. During this time, there were occasions when hydrogen sulphide concentrations in the air were above the WHO odour annoyance guideline value (5ppb / 7ug/m3).
We have also reviewed air quality monitoring by Geotechnology at other sites in the community between 7th September and 22nd September 2024. These monitoring data have not recorded any occasions when hydrogen sulphide concentrations in the air were above the WHO odour annoyance (5ppb / 7ug/m3) level. Air monitoring undertaken by Geotechnology using diffusion tubes has not identified levels of hydrogen sulphide above longer term guideline (1ppb – based on a lifetime exposure).
The long-term (lifetime) health risk remains low, however we understand that bad smells in your community can be upsetting and even at very low concentrations, bad smells can lead to headaches, nausea, dizziness, watery eyes, stuffy nose, irritated throat, cough or wheeze, sleep problems and stress. This can happen even when the substances that cause the smell are not directly harmful to health. These are common reactions, and these effects should usually pass once the odour has gone.
Closing windows and doors when smells occur can help to stop them coming inside homes. Remember not to block windows or vents completely. This is because they provide air to vent cookers or heaters and can help to control damp. Once an outdoor smell has passed, opening windows and doors will help get rid of any smells that remain.
Multi-agency partners review and check monitoring data together. Public Health Wales then use it to inform a health risk assessment before sharing our conclusions with the public. The health risk assessment will continue to be reviewed and updated as more monitoring data is made available to us.
We recognise the real stress and anxiety that local people are under as a result of these smells. However, PHW does not have regulatory responsibilities or powers around the management or enforcement of a site, including carrying out monitoring. We can advise regulators, the public and other partners, and contribute to public health risk assessments.
Published: 14 October 2024
Public Health Wales has undertaken a further health risk assessment of air quality data collected at the Spittal School monitoring station, covering the period between 27th August and 30th September 2024. During this time, there were occasions when hydrogen sulphide concentrations in the air were above the WHO odour annoyance (5ppb / 7ug/m3) level.
In addition, we have reviewed air quality monitoring undertaken by Geotechnology at other sites in the community between 9th August and 4th September 2024 and monitoring undertaken by Natural Resources Wales (also in the community) between 13th June and 4th September. These monitoring data have recorded one occasion when hydrogen sulphide concentrations in the air were above the WHO odour annoyance (5ppb / 7ug/m3) level.
Whilst these data are generally reassuring, we do know that, even at low concentrations, bad smells can lead to headaches, nausea, dizziness, watery eyes, stuffy nose, irritated throat, cough or wheeze, sleep problems and stress. This can happen even when the substances that cause the smell are not directly harmful to health. These are common reactions, and these effects should usually pass once the odour has gone. The long-term (lifetime) health risk remains low.
Closing windows and doors when smells occur, or when the wind is blowing from the landfill towards your home, can help to stop smells coming inside. Remember not to block windows or vents completely. This is because they provide air to vent cookers or heaters and can help to control damp.
Once an outdoor smell has passed, opening windows and doors will help get rid of any smells that remain.
Multi agency partners review and check monitoring data together. Public Health Wales then use it to inform a health risk assessment before sharing our conclusions with the public. The health risk assessment will continue to be reviewed and updated as more monitoring data is made available to us.
Published: 12 September 2024
Public Health Wales has undertaken a further health risk assessment of air quality data collected at the Spittal School monitoring station, covering the period between 1st July 2024 and 26th August 2024. No exceedances of the WHO odour annoyance (5ppb / 7ug/m3) level have been recorded.
In addition, we have reviewed air quality monitoring undertaken by GeoTechnology at other sites in the community between 4th June 2024 and 5th August 2024. This monitoring has recorded no exceedances of the WHO odour annoyance level.
It is reassuring that there are no exceedances of the WHO odour annoyance level for these periods. However, we understand that even at concentrations below this level, individual sensory responses can vary, and intermittent odours may have been experienced.
For some, bad odours or smells can lead to headaches, eye irritation, nausea, dizziness, and unusual tiredness, even when the substances that cause the odour are themselves not toxicologically harmful to health. These are common reactions, and these effects should usually pass once the odour has gone. The long-term (lifetime) health risk remains low.
Closing windows and doors when nasty smells occur, or when the wind is blowing from the landfill towards your home, can help to stop smells coming inside. Remember not to block windows or vents completely. This is because they provide air to vent cookers or heaters and can help to control damp.
Once an outdoor smell has passed, opening windows and doors will help get rid of any smells that remain.
The health risk assessment will continue to be reviewed and updated as more monitoring data is made available to us.
Published: 26 July 2024
Public Health Wales is confirming findings from a further health risk assessment of air quality data collected around the Withyhedge landfill site, covering the period between 3 April and 26 June 2024.
The data suggests that levels of hydrogen sulphide in the air around the site have at times been above the World Health Organization (WHO) odour annoyance guideline.
Public Health Wales advice therefore remains that residents should keep doors and windows closed when the smells are present, and to seek medical advice if they feel unwell.
Typically, when odours are above the WHO odour annoyance guideline value, there is potential for odour complaints and health effects. Everybody reacts differently. For some, bad odours or smells can lead to headaches, eye irritation, nausea, dizziness, and unusual tiredness, even when the substances that cause the odour are themselves not toxicologically harmful to health
These are common reactions, and these effects should usually pass once the odour has gone. The long-term (lifetime) health risk remains low.
Hydrogen sulphide is a gas that has a rotten egg smell. Our noses can smell very small amounts of hydrogen sulphide, even at levels that are too low to cause harm.
Public health advice to those exposed to the odours remains unchanged.
Closing windows and doors when nasty smells occur, or when the wind is blowing from the landfill towards your home, can help to stop smells coming inside.
Remember not to block windows or vents completely. This is because they provide air to vent cookers or heaters, and can help to control damp.
Once an outdoor smell has passed, opening windows and doors will help get rid of any smells that remain.
Public Health Wales maintains that reducing the cause or source of offsite odours from the landfill site must be a priority to reduce exposure and any potential health effects on the local community.
Dr Sarah Jones, Consultant in Environmental Public Health for Public Health Wales said:
“We recognise that local people continue to be concerned as a result of these odours, and that this air quality report continues to show levels of hydrogen sulphide above the World Health Organization (WHO) odour annoyance guideline.
“Public Health Wales remains eager to see a resolution to this situation. The health risk assessment will continue to be reviewed and updated as more monitoring data is made available to us.”
The air quality assessment is based on monitoring carried out by GeoTechnology Ltd, a contractor employed by RML, the Withyhedge site operator, at several locations around Withyhedge Landfill site between 3 April and 26 June 2024.
Published: 18 June 2024
Public Health Wales is reiterating its advice to residents in the area around the Withyhedge landfill site, following our health risk assessment of air quality data collected between 1 March and 3 April 2024.
Public Health Wales received the final data on 23 May 2024 to begin our risk assessment. The data suggests that, at times during March and April 2024*, levels of hydrogen sulphide** in the air around the site have been above the World Health Organization (WHO) odour annoyance guideline.
Public Health Wales advice therefore remains that residents should keep doors and windows closed when the smells are present, and to seek medical advice if they feel unwell.
When people are exposed to odours at levels above the WHO guideline value, they may experience effects such as headaches, nausea, dizziness, watery eyes, stuffy nose, irritated throat, cough or wheeze, sleep problems and stress.
These are common reactions to nasty smells, and these effects should usually pass once the odour has gone. The long-term (lifetime) health risk is low.
Public health advice to those exposed to the odours remains unchanged.
Closing windows and doors when nasty smells occur, or when the wind is blowing from the landfill towards your home, can help to stop smells coming inside.
Remember not to block windows or vents completely. This is because they provide air to vent cookers or heaters, and can help to control damp.
Once an outdoor smell has passed, opening windows and doors will help get rid of any smells that remain.
Public Health Wales maintains that reducing the cause or source of offsite odours from the landfill site must be a priority to reduce exposure and any potential health effects on the local community.
We note that work to cap the site has now been completed. Public Health Wales welcomes plans to position static air monitoring around the site going forward to help capture more detailed data.
Dr Sarah Jones, Consultant in Environmental Public Health for Public Health Wales said:
“We recognise the real stress and anxiety that local people are under as a result of odours around the Withyhedge landfill site. Like local residents, we are very eager to see a rapid resolution to this issue.
“The health risk assessment will continue to be reviewed and updated as more monitoring data is made available to us.”
Chair of the Air Quality Group for the Multi-Agency Incident Management team Gaynor Toft said:
“We note the risk assessment from Public Health Wales and continue to refine and develop the air quality monitoring programme in the vicinity of the landfill site. Suitable static monitoring locations are being identified for the siting of equipment.
“We continue to work in collaboration as the Air Quality Group to ensure that robust data is collated to inform future Public Health Wales assessments.”
Huwel Manley of Natural Resources Wales said:
“We acknowledge the report and will continue to use our regulatory powers to drive improvements on site to address causes of odour affecting the community.”
Withyhedge Air Quality Data Review
Public Health Wales 13th June 2024
Published: 3 June 2024
Public Health Wales have reviewed the air quality monitoring data provided to us and our initial public health assessment of that data does not give us any reason to change our advice. That is, if residents near Withyhedge experience odours from the landfill, closing windows and doors can help minimise odours; once the odour has passed, opening windows and doors again can help reduce any odours inside homes. Remember not to block windows or vents completely; this is because they provide air to vent cooking and heating appliances and to control damp.
In line with the agreed multi-agency approach, our assessment is being shared with partners to help inform action and further advice going forward. We will continue to review monitoring data made available to us to support the ongoing assessment of health risk locally.
In the interim, we recognise just how much of an impact the odours from the landfill continue to have on local communities and reiterate our call for urgent action to resolve this issue as soon as possible.
Published: 21 May 2024
Public Health Wales recognise that local people are very concerned about the odours around the landfill site at Withyhedge. We continue to call for improved air quality data to be provided, to allow us to make a health risk assessment of the site.
This is in addition to our original recommendation that urgent action was taken to address the source of the odours.
This week, Public Health Wales met with elected representatives of neighbouring communities near Withyhedge Landfill, regarding the issue of significant odours emanating from the site.
Since early this year, Public Health Wales have been working with Natural Resources Wales who are the lead agency managing this incident. It is possible that odours and emissions from the site may be harmful to health, but without data is difficult to know for sure. We have consistently presented advice that air quality monitoring is needed to gain an accurate understanding of the potential health impacts of emissions on the local community.
We have now received some long-term air quality data which is currently being reviewed. However, we are still awaiting additional short-term monitoring data as this will enable a more complete picture and allow a fuller assessment of any potential health impacts on neighbouring communities.
Our advice to people remains to keep windows and doors closed when the smells are present and to seek medical advice if necessary. We continue to advocate for urgent action to resolve this issue as soon as possible.
Dr Giri Shankar, Director of Health Protection for Public Health Wales, said:
“Public Health Wales have been advocating for the odours to be addressed urgently, as well as for detailed independent air quality monitoring to be carried out, for several months. This is the only way we can gain an accurate picture of the potential physical harms to health.
“Residents have been experiencing distress as a result of the foul smells and their need for a rapid solution is understandable. The impact on mental health should not be underestimated either. We continue to advocate for urgent action to find a resolution to this issue as soon as possible.”