Initial Steps to Prevent Lead Exposure and Poisoning from the Model National Lead Safety Policy Proposal created by The LEAD Group – vii-xi
vii) Use pathology reports to advise doctors and their patients as to options for accurate and reliable testing for the likely environmental lead sources that may have elevated their blood lead level
In some countries, government advice cautions about the lack of sensitivity and potential false results from hardware stores) for lead in paint, dust wipes, ceramics, and so on.
As noted above (in vi), blood lead pathology reports provide an indirect and consistent opportunity to advise of the accuracy of laboratory lead testing of paint, soil, surface dust wipes, ceiling dust, water, backyard eggs, food, traditional and complementary medicines, traditional cosmetics and other consumer products.
Chemical analysis laboratories which test for lead in all these sample types are generally not permitted to provide interpretation, advice or recommendations on how to respond to the lead results. As well, most laboratories don’t provide advice or information on sample for lead analysis, and don’t supply laboratory-grade sampling equipment for lead sample collection.
Given these limitations, it is prudent of the pathology laboratories to provide information on laboratory testing for environmental lead.
In Australia, LEAD Group Kits, (Australian Government Department of the Environment 2014), sold by the not-for-profit LEAD Group charity, are unique in the world for providing sampling instructions, advice and laboratory-grade sampling equipment, plus interpretation and individually tailored comments on the laboratory results with guidance as to priority mitigation measures. Clients can include individuals, government departments, shooting ranges, and environmental assessors, contractors, and public health officers (who collect the samples for the client). The advice provided on how to sample, what to sample, interpretation of results, and how to reduce blood levels in humans, animals (pets, backyard poultry and livestock, including “paddock pets”) is enormously advantageous compared to standalone laboratory test results or environmental sample x-ray fluorescence (XRF) screening results.
All environmental and consumer product sample types are covered by LEAD Group Kits within Australia. Outside Australia, USA and Canada, all other countries can currently access LEAD Group Kits if they are not testing the sample types which will not pass through Australian customs due to biosecurity risks, such as soil, water, eggs, breast milk.
If any country were to locate chemical and food/medicine laboratories which have the capacity to test for the presence of lead at low levels then the above sample types could be analysed in that country with a LEAD Group Kit, and this would bypass the biosecurity issue.
Where possible, within-country laboratory testing of lead, in all sample types via LEAD Group Kits will be sourced to avoid the need for international transportation of any samples. Such laboratories will need to possess the capabilities to detect lead at low levels across multiple sample types.
With local community group involvement that is already, or is prepared to, collaborate with a knowledgeable and experienced charity, such as The LEAD Group, the rest of the services could be provided in-country – namely the provision of laboratory-grade sampling equipment, instructions, interpretation and advice to the client on the laboratory results and how to reduce their blood lead levels. This would in-effect be an Australian lead-safety intellectual property export to help to offset the burden of Australia’s more than 120-year history of exporting lead.
Where DIY sampling kits which involve laboratory analysis and guidance, such as LEAD Group Kits, are available it would be beneficial for all patients to be advised of their availability (along with any government subsidy) within the blood lead pathology report.
viii) National governments will budget for the provision of affordable laboratory testing and guidance on lead results in potential environmental, food, and other sources of lead to individuals (of all ages)
Governments can also provide community-based lead testing DIY sampling kits, such as The LEAD Group’s Kits (described in vii, above) which come with guidance based on laboratory lead results in environmental, food, traditional and complementary medicine, and other samples as to how to reduce blood lead levels.
When national governments budget for the provision of this type of testing (including advice) on a means-tested basis, not only will blood lead levels fall but community not-for-profit organisations providing such services will be financially supported to carry out other lead safety programs.
ix) Determine and allocate responsibility for prevention of lead exposure and lead poisoning
Prevention of lead exposure and poisoning is commonly divided, in health literature, as consisting of Primary, Secondary and Tertiary Prevention.
Primary Prevention is concerned with preventing public/individual lead poisoning and/or exposure in the first place.
Predominantly, it is the responsibility of intergovernmental organisations and national governments.
Individuals can also take action to prevent lead exposure in their homes, workplaces, or leisure activity venues, such as shooting ranges. For example, prior to purchase or rental of residential properties, individuals may test for lead and decide to carry out abatement prior to moving in or elect not to purchase or rent the property.
Secondary Prevention follows the finding of an elevated blood lead level and is concerned with preventing further lead exposure in individuals by environmental testing and removing the individual from the source of lead exposure or removing the source from the individual.
The state or local health authorities have a significant role to play either in lead testing and/or support for the removal of the lead source or the person from the source of exposure.
A typical example would be removal of lead contaminated soil from a backyard, or laying geotextile on top of it, then providing clean topsoil and grass to prevent soil exposure of children, pets and backyard poultry.
Another example would be a person changing their occupation or place of residence to prevent being exposed to lead.
Secondary Prevention is more diversified and therefore it is not entirely possible to designate in advance whose responsibility it is. The responsibility for collecting, collating, analysing and raising awareness of the results of blood lead testing (and possibly environmental lead testing) rests with governments.
Tertiary Prevention is concerned with preventing the lead already in a person’s body from doing further harm (further than the harm done on the way into the organs and bone and teeth storage), including causing early morbidity and mortality.
Responsibility for Tertiary Lead Poisoning Prevention is also diversified from the individual experimenting with what reduces their own blood lead level to governments sponsoring long-term studies of the effects of certain treatment or intervention protocols.
There must be strategies for carrying out or encouraging all three forms of Lead Exposure and Lead Poisoning Prevention. These strategies need to be tailored to the specific circumstances of the particular country, but public awareness campaigns regarding the health effects of lead, possible sources and pathways of exposure, as well as what can be done to prevent exposure, cut off pathways, or reduce blood lead levels are essential.
Each country will establish both a national taskforce, like the President’s Task Force on Environmental Health Risks and Safety Risks to Children (US), and an advisory group similar to the Lead Exposure and Prevention Advisory Committee (US).
x) Carry out a National Blood Lead Survey of All Ages within 6 months of endorsing the National Lead Safety Policy on the Prevention and Management of Lead Exposure, Poisoning and Contamination
The first step in implementing a National Lead Safety Policy for preventing lead poisoning in a population is to do a baseline study – a National Blood Lead Survey of All Ages (across all age brackets).
Excellent examples of collation and analysis of national blood lead data collected since 1976 can be seen in the US Centers for Disease Control and Prevention (CDC 2021) National Health and Nutrition Examination Survey (NHANES), although children who receive Medicaid in the US are only required to have their first blood lead test at 12 months of age, thus missing potentially 6-months’ of lead exposure while crawling.
It is not a question of doing a survey to find out if anyone in the population of a particular country has lead in their blood because exposure to lead in some form or another is genuinely universal. A National Blood Lead Survey of All Ages is needed to develop specific strategies focused on sub-populations most at risk and then resurvey the population once the strategies have been implemented to evaluate their efficacy.
A National Blood Lead Survey of All Ages must include babies and children from at least age 6 months, as this is the age when crawling begins and therefore environmental lead exposure increases. The exception would be in lead mining and smelting (including lead-acid battery recycling/secondary smelting) towns, and near general aviation airports, where children as young as 4 months will be included due to the lead inhalation pathway.
Children 6-48 months old are at highest risk for lead exposure due to mouthing behaviours, pica, more efficient absorption, smaller size, and larger body burden.
Anybody seeking to conceive, those who are pregnant and women giving birth also need to be included in the National Blood Lead Survey of All Ages – cord blood can be collected during the birth and can be analysed for lead concentration.
Participants in the National Blood Lead Level Survey of All Ages will need to complete (or have their parent/guardian complete) a lead risk factor questionnaire and a general health questionnaire that specifically includes incidence of lead-related health outcomes in the person (and their family health history), such as all the at-risk individuals, listed at iv (above).
The lead risk factor questionnaire would include –
- For children and adults:
- Race, given that darker skinned people on average have higher blood lead levels than lighter skinned people in similar circumstances
- Gender, given that males typically have higher blood lead levels than females
- Date of birth (in preparation for being resurveyed, when the individual may have gone up an age bracket)
- Pica behaviour
- Year of construction and description of home (including condition of paint and presence of lead lighting or leaded windows, and lead flashing when rainwater runoff is allowed to empty onto soil, rather than being directed to a stormwater drainage system)
- Presence during or following renovation/s
- Home in a leaded community such as:
- Inner city
- Communities with lead, zinc, copper, tin, silver or gold mining or smelting operations
- Aluminium smelter communities (due to the use of leaded coal tar pitch in smelting aluminium)
- Communities around fossil fuel facilities or close to petrol stations
- Proximity to a general aviation airport
- Use of Ayurvedic medicine, given that if metal bhasmas are included the medicine is likely to contain lead (and other heavy metals)
- Whether anyone smokes in the household
- Consumption of backyard chicken eggs
- Consumption of homegrown root vegetables
- Consumption of locally sourced fish or seafood
- Consumption of water from:
- A tank (including whether there is lead flashing in the rainwater collection area and whether the rainwater is collected in a lead mining and smelting community or near general aviation flightpaths), dam, river, bore, or well
- Lead pipes
- Lead-soldered pipes
- A new brass tap installed within the previous three years
- Whether anyone living in the house has occupational and/or hobby exposure to lead, for example, in paint (including artists’ paints for adults), glazes, alloys, solders, leadlighting
- Whether anyone living in the house is a shooter, fisher or hunter, or makes bullets or fishing sinkers at home
- If the home is carpeted
- Use of ceramicware that is in poor condition (chipped, crazed glazing, dishwasher-damaged, microwave oven-damaged and so on) particularly if antique and/or used to hold acidic, alcoholic or hot foods or beverages, or to heat food or beverages
- Use of leaded crystal glassware for acidic, alcohol or hot food or beverages, or to heat food or beverages
- Use of turmeric, especially if sourced from India, Bangladesh or Georgia
- Use of cosmetics, such as kohl
- The presence of exposed soil (non-grassed, mulched or paved)
- For children:
- Chewing or mouthing of potentially leaded items (such as painted toys, jewellery),
- Year of construction of any other building/s where the child spends a significant amount of time and the renovation history of the building
- Regular use of lead-painted playground equipment or play areas made from either tyre crumb or leaded PVC artificial turf
- For adults:
- Consumption of alcohol and/or cigarettes
- Pregnant or breastfeeding
- Perimenopausal or menopausal
- Occupational and/or hobby exposure to lead
This health history combined with data collection about lead exposure risk factors will enable the results to be immediately useful across a variety of research areas.
A National Blood Lead Survey of All Ages will also include testing for levels of iron, zinc and iodine, as these trace elements have a connection with lead and its effects, noting that both serum iron and ferritin are acute phase reactants and can vary significantly due to other factors. Low levels of iron and zinc in the blood increase the rate of uptake of lead. Iron and iodine deficiency can be mistaken for problems with brain development, one of the effects of lead poisoning.
Because of the negative impacts of both COVID-19 infection/s on heart health (Raisi-Estabragh 2022) and lead exposure, and the increased risk of all-cause mortality of both COVID-19 and lead, a National Blood Lead Survey of All Ages will include all known incidences of COVID-19 in the person and parameters of heart health in order to determine whether there is a relationship whereby people who have a higher blood lead level are more likely to die from heart attack or stroke following COVID-19 infection/s.
xi) Further research the lead sources and pathways for National Blood Lead Survey of All Ages participants who have blood lead levels above the current action level
Those participants of the National Blood Lead Level Survey of All Ages who have a blood lead level which exceeds the national action level will offered government-funded laboratory testing of their likely sources of lead, starting with the usual soil, surface dust wipe, degraded paint, and water sources. Cases will be followed up until the blood lead level falls below the action level.
The likely lead sources and pathways for an individual can also be determined by using “isotopic fingerprinting” and other research techniques on blood, environmental samples, food, drink, cigarettes, ceramicware and so on.
This method is described in a paper presented at Standards Australia Conference “Lead in Blood” in 1993 by Emeritus Professor Brian Gulson (founding head of The LEAD Group’s Technical Advisory Board) and Karen Mizon, CSIRO, “Lead Isotope Method – Lead in Blood”:
The lead isotope fingerprinting method makes use of the fact that the abundance of the isotopes of Pb [lead] from one geological source can be quite different to the abundance of the isotopes from another geological source. For example, Pb in Australia generally has a totally different profile (a 206Pb/204Pb of 16.0 –16.5) to that of Pb from Europe (206Pb/204Pb > 18.0). The profiles or abundances of the Pb ores are also usually quite different from those of Pb in the common rocks which surround the mineral deposits.
In using the fingerprinting method for determining the source of Pb in, for example, people, the researchers compare the Pb isotope profiles in blood and/or urine (but can also use nails and teeth) with those found in the potential environmental sources such as air, food, water and dust. In simple terms, the closer the similarity in isotope profiles between that in blood and an environmental source or sources indicates that the environmental sources may be a significant contributor to the Pb in blood.Emeritus Professor Brian Gulson and Karen Mizon
Doing isotopic fingerprinting and analysis on the blood and relevant samples for each individual whose result was above the current action level is an essential follow-up to the national blood lead survey.
Even older participants’ sources of lead exposure from earlier in their lives may be able to be identified and thus provide information to help identify patterns of lead exposure over time where that person grew up (see 2.4, below).