Ambient air sampling for beryllium in the environment and environmental monitoring

The CNSC has carried out extended ambient air monitoring for beryllium near the BWXT Nuclear Energy Canada Inc. (BWXT-NEC) Peterborough facility. This monitoring demonstrates that levels of beryllium are low, and are also well below air quality guidelines that are protective of human health and the environment.

This page aims to provide information about the air monitoring campaign, as well as answers to questions from members of the public about environmental monitoring and health.

On this page

• No fugitive beryllium emissions from the BWXT-NEC Peterborough facility
• Extended environment ambient air monitoring for beryllium near the BWXT-NEC Peterborough facility
• Sampling methods the CNSC follows for air monitoring near the BWXT-NEC Peterborough facility
• Justification for no routine or continuous environment ambient air monitoring at the BWXT-NEC Peterborough facility
• When environmental ambient air monitoring is required at the BWXT-NEC Peterborough facility
• Recent changes in the Independent Environmental Monitoring Program (IEMP) soil sampling methodology and the difference between partial and full digestion
• The CNSC’s interpretation of the results from IEMP sampling conducted in 2020 and 2021
• Future IEMP sampling planned for the BWXT-NEC Peterborough facility
• CNSC verification that equipment and air emissions monitoring systems are performing as intended at the BWXT-NEC Peterborough facility
• Long-term human health impacts related to exposure to uranium or alpha emitters
• References

No fugitive beryllium emissions from the BWXT-NEC Peterborough facility

There are no fugitive beryllium emissions from the BWXT-NEC Peterborough facility, based on the design and operation of the facility and monitoring programs. Fugitive emissions are a form of air pollution derived from human activities that do not originate from a particular point, such as an exhaust pipe or stack.

At various points of the BWXT-NEC beryllium process, there is monitoring for contamination to ensure that the hazard is contained. The workers use personal air monitoring to ensure that their exposure is determined, and kept to a minimum and within regulatory limits. The room and work surfaces are monitored for any contamination and cleaned to maintain air and surface contamination below specified levels.

This facility uses several levels of “defence in depth” (a concept where multiple redundant safety systems are used, in case one system fails) to ensure that beryllium emissions are kept as low as possible:

• Any air particulates in the room air collected by the facility ventilation systems are removed through a filtration system before the air leaves the facility through the stacks.
• The facility is designed to be under negative pressure. Any air flow from where the processes occur is in one direction only.
• The stacks are continuously monitored for beryllium releases with limits and action levels.

Stack monitoring results show that the beryllium emissions are low and below the Ontario Ministry of the Environment, Conservation and Parks’ Ambient Air Quality Criteria of 0.01 micrograms per cubic metre (µg/m³) prior to any dilution – with a maximum concentration ever measured at the stack of 0.009 µg/m³. The monitoring is done with a particulate filter system in the stack and filters are collected weekly and analyzed. This is reported to the CNSC annually; however, should any result exceed an action level, it would be required to be reported right away.

Extended environment ambient air monitoring for beryllium near the BWXT-NEC Peterborough facility

The CNSC has heard several community concerns related to beryllium emissions from the BWXT-NEC facility in Peterborough. Currently, the CNSC requires the licensee (BWXT-NEC) to monitor all emissions at the source (stacks) as well as to monitor the receiving environment (soil) to demonstrate that the environment around the BWXT-NEC facility is safe.

In 2021, the CNSC solicited feedback to learn about concerns from the community. It was suggested that additional air monitoring, to verify that the air is safe around the BWXT-NEC facility, would alleviate community concerns and increase public trust in existing environmental monitoring.

The CNSC has been working with Dr. Aherne from Trent University to develop a community-specific air monitoring plan. Dr. Aherne suggested extending air sampling over at least 3 days (72 hours) at locations based on consideration of wind direction. The CNSC conducted a walkabout with Dr. Aherne to identify possible sampling locations around the facility. Sampling was carried out at locations with a favourable wind direction and where a power supply was available.

Sampling methods the CNSC follows for air monitoring near the BWXT-NEC Peterborough facility

A Hi-Q high-volume 3300BRL air sampler with cellulose filters (Whatman 41) is used to collect samples. Cellulose filters have very little (if any) measurable background beryllium, which makes them preferable over glass-fibre filters with relatively high and variable levels of beryllium. Samples are analyzed using microwave-assisted filter digestion, and this is followed by ICP-MS analysis, according to EPA 6020B ^{Footnote 1}.

The samples are prepared for elemental analysis by first cutting a sub-sample out of each air filter. Each sub-sample is further cut into small pieces and digested using the laboratory microwave digestion. The acid digestion results in complete dissolution of cellulose filters and collected particles. An aliquot of the digest is then diluted with acid solution containing an internal standard and analyzed by an inductively coupled plasma mass spectrometer (ICP-MS).

ICP-MS analysis provides accurate and sensitive elemental concentrations at very low levels. With each batch of air filter samples that are collected from a site, quality-control samples (i.e., air filter field blanks and filters spiked with beryllium) as well as digestion blanks are also analyzed.

Justification for no routine or continuous environment ambient air monitoring at the BWXT-NEC Peterborough facility

The environmental risk assessment (ERA) for the BWXT-NEC facility in Peterborough evaluates risks associated with releases of nuclear and hazardous substances to the air and water due to facility operations. The ERA identified uranium and beryllium as the principal contaminant emissions to the air from BWXT-NEC operations. These emissions are continuously monitored at a single-process uranium exhaust and 3 beryllium exhaust vents to fully reflect requirements of CSA standards for effluent and environmental monitoring.

Monitoring results at the release points from 2012 to 2016 for both potential contaminants were significantly below the provincial (MECP) standards for ambient air and other regulatory requirements. Therefore, the ERA concluded that routine monitoring of ambient air near the facility is not warranted.

When environmental ambient air monitoring is required at the BWXT-NEC Peterborough facility

The BWXT-NEC Peterborough facility was issued a renewed licence in December 2020. In the renewed licence, the Commission authorized BWXT-NEC to conduct pelleting operations in Peterborough (currently conducted in Toronto), with additional conditions that the licensee would have to fulfil before moving these operations to Peterborough.

The licence conditions require BWXT-NEC Peterborough to establish an acceptable ambient environmental monitoring program before commencing any pelleting operations at the facility. The licensee has not yet notified the CNSC of its intent to move the pelleting operation to Peterborough.

Recent changes in the Independent Environmental Monitoring Program (IEMP) soil sampling methodology and the difference between partial and full digestion

For the purpose of CMD 20-H2.D, CNSC staff completed a thorough review of the IEMP methodology used in the field. Over the years, the CNSC has adopted improved sampling techniques, so different sampling procedures were used in 2014 versus 2018­–20. In 2014, soil was sampled using a shovel, whereas in a core sampler was used in 2018, 2019 and 2020. These changes may have contributed to the relatively lower variability of total beryllium concentrations reported in 2018, 2019 and 2020 compared to 2014.

The samples collected in July 2020 were analyzed at the CNSC laboratory using the total digestion ^{Footnote 2} method, similar to 2014, 2018 and 2019. By using a potent acid mixture, the total digestion method leads to a total decomposition and dissolution of the investigated sample, thus giving both environmentally available and otherwise insoluble portions of the element. The insoluble portion of beryllium cannot be digested by humans or animals and simply passes through the digestive tract without being absorbed into the blood. The concentrations of elements determined using the total digestion of soil are useful for geological studies and forensic work, because they reflect its mineralogical make-up and origin. In contrast to total digestion method, partial digestion ^{Footnote 3} liberates soluble beryllium, which can enter the blood of humans and animals if ingested.

In 2020, the soil samples were also analyzed by partial digestion method. Partial digestion results in lower beryllium concentrations in soil as this method does not break down and dissolve certain minerals, such as silicates and zircons ^{Footnote 4Footnote 5Footnote 6Footnote 7}. The bioavailable portion of an element is determined by partial digestion and allows direct comparison to the MECP soil standard that outlines natural background ranges for beryllium for different land uses and is based on this analytical method. The Peterborough area beryllium concentrations in soil are within natural background range as established in this standard.

Analysis by partial digestion also allows direct comparison with the Canadian Council of Ministers of the Environment soil quality guidelines for beryllium. CNSC staff use these guideline’ for the protection of environmental and human health, when interpreting results for beryllium in soil, which are based on the bioavailable concentrations obtained by partial digestion. These guidelines are used by the CNSC to determine if soil concentrations of potential contaminants observed near nuclear facilities may present a risk to the environment and public health. All future soil analysis will be done using partial digestion methods.

The CNSC’s interpretation of the results from IEMP sampling conducted in 2020 and 2021

The levels of uranium and beryllium measured in the samples were below maximum levels specified in available guidelines. Measurements conducted the IEMP to date have consistently found levels of radioactivity in the environment to be low, and well within the range of natural background radiation levels. All measured concentrations of beryllium in soil around the BWXT-NEC Peterborough nuclear facility are consistent with the background values and their temporal variations. The concentrations of beryllium in soil collected around BWXT Peterborough remain well below guidelines. As a result, no health or environmental impacts are expected at these concentrations.

Future IEMP sampling planned for BWXT-NEC Peterborough facility

The next IEMP sampling campaign at BWXT-NEC Peterborough is planned for 2025. This date could be adjusted if necessary.

CNSC verification that equipment and air emissions monitoring systems are performing as intended at the BWXT-NEC Peterborough facility

The CNSC conducts planned onsite inspections and desktop reviews to ensure that air emissions monitoring systems are performing as intended. As well, during inspections CNSC staff have direct, independent access to workers performing beryllium-coating operations to review any performance- or operations-related issues.

Long-term human health impacts related to exposure to uranium or alpha emitters

It is known that alpha radiation can result in statistically observable increased risk of cancer in populations exposed at moderate (~100 mSv to 1000 mSv) and high doses (>1000 mSv). The International Commission on Radiation Protection estimates an increasing risk of cancer of about 5% per sievert (1000 mSv). Nonetheless, at low and very low doses (<~100 mSv), more typical of environmental and occupational doses, changes in the occurrence of cancer, although biologically plausible, have not been confirmed in epidemiology studies. At these doses radiation-related cancer is not discernible from background cancer rates within the population.

CNSC regulatory dose limits are based on rigorous consultation and review of the work of several international expert organizations, such as the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) and the International Commission on Radiological Protection. In the 2016 report, UNSCEAR assessed the levels and effects of exposure to uranium by synthesizing peer reviewed scientific literature. Epidemiological studies of uranium workers find only weak associations between uranium exposure and lung cancer risk, and the currently available results are not consistent enough to demonstrate a causal association. Results for other cancers and non-cancer diseases were also negative.

UNSCEAR's scientific findings underpin radiation risk evaluation and international protection standards. Conclusions are revised as needed to incorporate new or emerging scientific findings. Maintaining doses below limits, and at levels that are as low as reasonably achievable, ensures that people are protected from the potential harmful effects of radiation – both currently and in the long term.

Today’s workers receive very low radiation doses. BWXT-NEC Peterborough’s urinalysis monitoring data found that inhalation hazards at the facility are negligible and that resulting doses are extremely small. These workers are safe and protected.

CNSC staff keep abreast of any new publications and data related to the health of populations living near nuclear facilities and nuclear workers. Based on exposure and health information, CNSC staff have not observed and do not expect to observe any adverse health outcomes due the presence of BWXT NEC Peterborough. The CNSC has published its health studies online.