Lead Diagnosis in Switzerland

Lead in old buildings: an underestimated hazard

Lead is one of the metals most long-used by humankind, and its presence in buildings constructed before the 1970s is far more widespread than is generally believed. Unlike asbestos, whose ban in Switzerland is precisely dated to 1 March 1990, lead was progressively abandoned in building applications over several decades, with no single prohibition date applying to all its uses.

In buildings predating the 1960s, the probability of encountering paints or renders containing lead is high. Between 1960 and 1985, the risk persists depending on the products used. For more recent buildings, the risks associated with lead in paints are low, but old lead pipework may still be present in certain buildings from the 1970s.

White lead and lead-based paints: where are they found?

White lead (basic lead carbonate) was one of the most widely used white pigments in paints until the mid-twentieth century. It offered excellent coverage, good durability and satisfactory moisture resistance, making it the preferred product for interior and exterior paints.

The surfaces most likely to contain lead-based paints in old buildings are:

• Interior joinery: windows (frames, sashes, sills), doors (surrounds, panels), staircases (handrails, balusters, treads), old varnished parquet floors, kitchen joinery.
• Walls and ceilings: in buildings constructed before 1960, successive coats of wall paint may form superimposed layers, the oldest of which contain lead. Old finishing renders may also contain lead.
• Exterior facades: paints on masonry, paints on exterior joinery (shutters, entrance doors, window surrounds).
• Metal structures: anti-corrosion paints on metal frames, guardrails, railings, ironwork, metal gutters and downpipes. Red lead paints were widespread for protecting steel structures.
• Radiators and pipework: certain paints on cast iron (old radiators) and on pipework contain lead.

Lead pipework: a water quality issue

Distinct from the question of paints, lead may be present in the plumbing installations of old buildings. Lead water distribution pipes were common in buildings constructed up to the 1970s, and sometimes beyond. Lead connections or joints may persist even in buildings that have undergone partial plumbing renovation.

The presence of lead pipework is a water quality problem distinct from the question of building materials: lead can migrate into drinking water, with a health risk that is particularly significant for infants and young children. This issue is more a matter of specialist plumbing inspection than building pollutant diagnosis in the strict sense.

Health risks of lead: lead poisoning

Lead is a cumulative toxin that accumulates in the body — primarily in the bones — over the course of exposures. Its health effects depend on the absorbed dose, the duration of exposure and the age of the person exposed.

Young children are the most vulnerable population. Their developing brains are particularly sensitive to the neurotoxic effects of lead. Lead poisoning in children — saturnism — can cause cognitive developmental delays, behavioural disorders and reduced learning capacity. These effects can be permanent and irreversible. Children are exposed primarily through ingestion of dust or flakes of lead-based paint (hand-to-mouth behaviour), but also through inhalation during construction works.

Adults are less sensitive to neurological effects, but prolonged or intense exposure can cause neurological disorders, kidney damage, cardiovascular effects and fertility problems. Construction workers operating on lead surfaces without appropriate protection are exposed to documented occupational risks.

During construction works, sanding, scraping, high-pressure projection or combustion of lead-painted surfaces releases dust and vapours containing lead. Without adequate protective measures, concentrations can be very high in the work zone and adjacent rooms.

The Swiss regulatory framework

In Switzerland, lead in building materials is regulated by several texts:

• The Ordinance on Construction Work (OTConst) requires the employer to ensure, before any construction site on an old building, that workers will not be exposed to hazardous substances. Lead falls into this category: before any work on painted surfaces in a building constructed before the 1970s–1980s, verification of lead presence is required.
• The occupational exposure limit values set by Suva define the maximum permissible concentrations of lead in workplace air. Exceeding these values requires reinforced protective measures.
• The Ordinance on the Movement of Waste (OMoD) subjects waste containing lead to specific disposal rules according to its content. Waste heavily loaded with lead is classified as special waste.
• Water quality legislation governs the permissible lead content in drinking water and requires water distributors and property owners to take measures if lead pipework causes limit values to be exceeded.

Lead detection methods

X-ray fluorescence (XRF) measurement

The portable X-ray fluorescence device is the reference tool for rapid screening of painted surfaces. It allows the lead content in paint layers to be measured in a few seconds, without destructive sampling. The measurement can be carried out directly on-site at multiple points of the same surface, with an immediate indication of concentrations.

Results obtained by XRF are compared with applicable regulatory thresholds or recommendation thresholds. This method is particularly suited to screening inspections covering many surfaces.

Sampling and laboratory analyses

Micro-samples of paint or render can be sent to an accredited laboratory for quantitative chemical analysis. This method provides precise results, with a lead content value expressed in mg/kg or mg/cm². It is used to confirm XRF results, for analyses on particular materials or to meet specific regulatory requirements.

Combination of both methods

In practice, the XRF method is used for initial screening across all zones concerned, and laboratory samples are taken in addition on surfaces presenting high concentrations or particular situations.

How a lead diagnosis works

• Inspection phase: the specialist inspects the zones concerned by the works or assessment. They identify all surfaces likely to contain lead-based paints and assess their condition (intact, slightly degraded, heavily degraded, flaking).
• XRF measurements: X-ray fluorescence measurements are taken on the identified surfaces, with documentation of locations and values obtained.
• Supplementary sampling: if necessary, samples are taken for laboratory analysis.
• Report: the lead diagnostic report specifies the location of surfaces with lead above threshold values, the concentrations measured, the state of conservation of coatings, and action recommendations (removal before works, confinement, protection during interventions, monitoring).

Lead diagnosis in Geneva and the canton of Vaud

In Geneva and the canton of Vaud, buildings constructed before 1960 are the most likely to contain lead, particularly in interior paints and pipework. Buildings in the historic centre of Geneva, Lausanne Haussmann-style buildings and Belle Époque villas are particularly concerned.

Our team operates in all municipalities of both cantons for standalone lead diagnoses or combined with an asbestos diagnosis. The multi-pollutant approach allows all regulated substances to be covered in a single intervention.

Multi-pollutant approach: lead and asbestos in the same diagnosis

In old buildings, the simultaneous presence of lead and asbestos is frequent. A building from the 1950s may contain both white lead paints on its joinery and asbestos-containing materials in its technical installations, roof or floor coverings. Carrying out both diagnoses simultaneously allows the specialist’s travel to be optimised, the overall cost of diagnoses to be reduced and a complete picture of health risks to be obtained before works.

A multi-pollutant approach, also integrating PCBs, PAHs and HBCD depending on the period and type of construction, is often the most efficient and economical solution for heavy renovation or demolition projects.

For a combined asbestos and lead mission, or for any building pollutant diagnosis in Western Switzerland, visit our asbestos diagnosis Western Switzerland page or request directly a personalised quote.