The LEAD Group’s Strategy for Minimising Lead Exposure
By Elizabeth O’Brien, BSc, Grad Dip Ed (Health Education), Lead Scientist and Lead Advisor, The LEAD Group
Minimising Lead Exposure in Australia – The LEAD Group’s strategy
Minimising lead exposure in Australia, and the rest of the world is essential for many reasons. In this paper, we’ll be exploring The LEAD Group’s strategy for doing this.
In light of the research summarised here:
- Dangers of a Blood Lead Level above 2 µg/dL and below 10 µg/dL to children
- Dangers of a Blood Lead Level above 2 µg/dL and below 10 µg/dL to adults
- Health effects of a blood lead level below 10 µg/dL in both adults and children and even below 1 µg/dL in pregnancy
And in this letter to the Medical Journal of Australia:
- Eliminating childhood lead toxicity in Australia: a call to lower the intervention level (Taylor, Winder, Lanphear, 2014)
The best blood lead result is one which contains a less than sign [<].
And a better blood lead action level for any child or adult is the limit of detection (1 or 2 micrograms per decilitre)
The ideal target blood lead level is to be below the limit of detection (or below 1 microgram per decilitre if the limit of detection is lower than 1 microgram per decilitre).
In other words, The LEAD Group recommends that action be taken if any member of the family does not have a < in their blood lead results, OR if the lab results exceed any of our recommended lead levels.
Goals in Minimising Lead Levels
As is stated in Taylor, Winder, Lanphear:
In order to achieve any new lower exposure goals other relevant lead standards including air, dust, soil and water must also be revised downwards and lead exposure from soils and dusts in Australian communities is dominated by three sources:
- mining and smelting emissions,
- lead paint and
- leaded petrol.…
though exposures are often a complex mix of sources…. soil in gardens and parks in many of the older, inner city areas of Australia became heavily contaminated with lead (Davis and Birch, 2011; Davis et al., 2011; Laidlaw and Taylor, 2011; Laidlaw et al., 2014a) and it is these sources that continue to expose children to potentially adverse levels of environmental lead.
In contrast, smaller rural towns with lower vehicle use and population densities, and no mining and smelting industries are likely to have a less significant legacy of environmental lead exposure compared to major lead mining and smelting cities (Taylor et al., 2010).
Exceptions in these locations include older housing where lead paint was used or where the source of drinking water is rainwater, river water or groundwater which has not been tested for lead (Green, 2013).
Therefore, efforts should be made to ensure soil and dust wipe lead levels are as low as possible.
Why We Need Guidelines to Minimise Lead Exposure
Guidelines should be regularly reviewed to take into account research into the health effects of low blood lead levels like 5 micrograms per decilitre (5 µg/dL). Indeed the World Health Organisation wrote (December 2010) :
Recent research indicates that lead is associated with neurobehavioural damage at blood levels of 5 μg/dL and even lower. There appears to be no threshold level below which lead causes no injury to the developing human brain. The Joint FAO/WHO Expert Committee on Food Additives re-evaluated lead in June, 2010 and withdrew the provisional tolerable weekly intake guideline value on the grounds that it was inadequate to protect against IQ loss.
Blood Lead Levels
On 19 May, 2015, Australia’s National Health and Medical Research Council (NHMRC) released their Statement and Information Paper: Evidence on the Effects of Lead on Human Health.
According to an email sent by the NHMRC on that day,
The NHMRC Statement advises that a blood lead level greater than 5 micrograms per decilitre suggests that a person has been, or continues to be, exposed to lead at a level that is above what is considered the average ‘background’ exposure in Australia. If a person has a blood lead level greater than 5 micrograms per decilitre, it is recommended that the source of exposure should be investigated and reduced, particularly if the person is a child or pregnant woman. Identifying and controlling the source of lead exposure will reduce the risk of harm to the individual and to the community.
The LEAD Group strongly objects to the phrase, “exposed to lead at a level that is above what is considered the average ‘background’ exposure in Australia”.
The term “average” is a statistical term and should never be applied to an “opinion” or “what is considered”.
It is dangerous to accept this opinion as to what is the average blood lead level in Australia, when in fact, the actual average blood lead level in Australia is likely to be much lower than 5 micrograms per decilitre (5 µg/dL).
It has been observed in every other country which undertakes blood lead surveys of their population that the average blood lead level in all age groups, drops markedly following the elimination of leaded petrol –
Leaded Petrol was phased out in Australia as of 1 January 2002.
Whilst the NHMRC (2015) does at least acknowledge that:
The average blood lead level among Australians is now estimated to be less than 5 micrograms per decilitre. This level is likely to decrease further over time as the presence of lead in the environment continues to reduce.
And yet, it is not at all clear as to how the NHMRC is proposing that lead in the environment will reduce.
Governments and Their Role
The Australian Federal Government and State and Territory Jurisdictions have long struggled with the concept that when you turn off the flow of lead into the environment (e.g., by phasing out leaded petrol or banning the addition of lead to new paint) you also have to clean up and manage the existing lead in the environment in order to reduce lead exposure.
The Australian Government needs to be far more proactive in creating strategies (policies, legislation, etc. – see our Model National Public Health Policy) to assist individuals to identify sources of lead and manage their lead exposure, especially targeting lead poisoning prevention.
The NHMRC (2015a) states:
If a person has a blood lead level greater than 5 micrograms per decilitre, it is recommended that the source of exposure should be investigated and reduced, particularly if the person is a child or pregnant woman. Identifying and controlling the source of lead exposure will reduce the risk of harm to the individual and to the community.
The LEAD Group has been calling for a national blood lead survey of all ages in Australia to be done for close to 30 years, and yet no such survey has ever been carried out.
Only one national blood lead study, on children aged 12-48 months has ever been published in Australia (in 1996) and the average then was above 5 micrograms per decilitre.
However, with the elimination of leaded petrol in Australia on 1st January 2002, the average blood lead level for both genders and across all age groups, should have fallen well below 5 micrograms per decilitre today.
The danger of not doing a national blood lead survey of all ages, is that doctors will believe the opinion of the NHMRC that blood lead levels up to 5 micrograms per decilitre are “average” and therefore not worthy of taking action to identify lead sources and abate the sources or abolish the lead pathway or remove lead from the body (if the lead exposure happened much earlier and is not affected by current abatement of lead sources).
The NHMRC simply MUST inform medical professionals that 5 micrograms per decilitre has been chosen as the action level for economic reasons and not because it is the average level.
The LEAD Group calls on the NHMRC to undertake a GP education campaign regarding lead poisoning, emphasising that the only non-actionable level of lead in blood is one that is below the limit of detection of the laboratory, as well as emphasising the need for more data on actual blood lead levels (preferably a study) and notification by labs and collation by government of ALL blood lead results for statistical analysis.
The LEAD Group recommends to the NHMRC and Australian Health Professionals that the new NHMRC level of 5 µg/dL be renamed the priority action blood lead level.
What’s a Safe Blood Lead Level?
In The LEAD Group’s Info Pack 56 – Changing ideas about what is a safe blood lead level, you’ll will read that our Technical Advisers recommend that Australia follow the Canadian proposal to lower the blood lead goal to one-tenth of the 1993 Australian and 1991 US level of 10 micrograms per decilitre, that is, 1 microgram per decilitre (1 µg/dL).
However, some Australian Labs have a limit of detection for blood lead analysis of 2 µg/dL, and thus the above recommendation. A better target blood lead level is to be below the limit of detection (or below 1 µg/dL if the limit of detection is lower than 1 µg/dL).
Put another way, The LEAD Group recommends any blood lead result which does not have a less than sign (<) is a blood lead level requiring action, or action blood lead level and that any blood lead result above 5 µg/dL is the priority action blood lead level.
The LEAD Group further calls on the Australian Government (probably the Federal Department of the Environment) and all State Environment & Consumer Protection agencies, to ban the addition of lead to all consumer products where it can be readily replaced by safer alternatives, and to make more stringent (revised downwards) all standards, guidelines, licence limits and regulatory (e.g. occupational and rental) triggers for lead levels in food, air, soil, dust and paint on surfaces, sediment, building cavity dust, agricultural additives (fertiliser, soil additives, etcetera), water (waste water, recreational waters, drinking water, stock water, etc.), tobacco products, and so on.
For instance, the Australian “occupational trigger level” for lead in paint is long overdue for revision downwards from the current 1%.
It is for this reason that The LEAD Group has recommended (since 2013!) that lead-safe methods be used to work on paint with a lead content greater than 0.1%.
The LEAD Group’s recommendation was vindicated in 2017 when Australian Standard 4361.2 on lead-safe management of old paint, changed the definition of Lead Paint from paint containing more than 1% lead, down to paint containing more than 0.1% lead.
What Can YOU Do?
Please write to your local member to add your voice to The LEAD Group’s latest call for improved lead policy in Australia – an email sent to the federal Health department in January 2022 included:
Noting that the US CDC reduced their blood lead “action” level from 25 µg/dL to 10 µg/dL in 1991, from 10 µg/dL to 5 µg/dL in 2012 and from 5 µg/dL to 3.5 µg/dL in October 2021, and we followed suit two years later in 1993 and three years later in 2015 respectively for the first two steps, can we possibly save time by cutting out all the discussion and just follow suit on the change to 3.5 µg/dL in 2022?
The year is now 2023 and Australia’s blood lead notification level is still at 5 µg/dL…
So please ask your local member to insist that Australia keep up with the US on lead policy and do whatever you can in the meantime to keep your family safe from lead.
References:
National Health and Medical Research Council (NHMRC) (2015) “Statement and Information Paper: Evidence on the Effects of Lead on Human Health” Online. Previously available at https://www.nhmrc.gov.au/media/releases/2015/nhmrc-releases-statement-and-information-paper-impacts-lead-human-health
National Health and Medical Research Council (NHMRC (2015a) Statement and Information Paper: Evidence on the Effects of Lead on Human Health Online. Available at https://www.nhmrc.gov.au/guidelines-publications/eh58
Taylor, Winder, Lanphear (2012) “Eliminating childhood lead toxicity in Australia: a call to lower the intervention level” in The Medical Journal of Australia 197 (9) p493 Online. Available at https://www.mja.com.au/system/files/issues/197_09_051112/letters_051112_fm-7.pdf
Taylor, Winder and Lanphear “Australia’s leading public health body delays action on the revision of the public health goal for blood lead exposures” Environment International Vol 70, Sept 2014, pages 113-117 https://doi.org/10.1016/j.envint.2014.04.023
The LEAD Group (n.d.) Info Pack 56 – Changing ideas about what is a safe blood lead level Online. Available at http://www.leadsafeworld.com/safe-blood-lead-level/
The LEAD Group (2011) Dangers of a blood lead level above 2 µg/dL and below 10 µg/dL to children Online. Available at https://www.lead.org.au/fs/Dangers_of_BPb_Level_Above_2ug_children_20101202.pdf
The LEAD Group (2011) Dangers of a blood lead level above 2 µg/dL and below 10 µg/dL to adults Online. Available at https://www.lead.org.au/fs/Dangers_of_BPb_Level_Above_2ug_Adults_20101202.pdf
The LEAD Group (2020) Health effects of a blood lead level below 10 µg/dL in both adults and children and even below 1 µg/dL in pregnancy Online. Available at https://leadsafeworld.com/wp-content/uploads/2020/09/Health-Effects-of-PbB-Level-Below-10-ug-per-dL-Even-Below-1-ug-per-dL-20200922.pdf
World Health Organisation (WHO) (2010) Childhood Lead Poisoning Online, available at: https://apps.who.int/iris/bitstream/handle/10665/136571/9789241500333_eng.pdf?sequen