This is a risk perception bulletin. Lead

What is lead?

Elemental lead is a soft, dense, silver-gray metal that is highly malleable with a melting point of 327 °C and a boiling point of 1740 °C.

Lead is relatively easy to extract from its natural minerals and combined with its abundance and physical property has proven useful to humans throughout history. In modern society, due to its known toxicity, uses and applications are limited.

Although relatively stable and non-reactive, lead and inorganic lead compounds are widely used in all sectors. Industrial processes can generate lead dust, fumes or vapours that pose a health risk.

Lead alkyl (organic lead), mainly used in the petrochemical sector, is not covered in this bulletin.

How could lead affect me?

Workplace exposure to lead can lead to a wide range of adverse health effects: some may arise from acute short-term exposures, others from chronic, repetitive and long-term exposures.

Acute health effects due to production or manufacture

• Non-specific with fatigue (exhaustion)
• Abdominal cramps and constipation
• Myalgia (muscle pain)
• Anorexia

Chronic health effects due to metallurgical production or manufacture

• Peripheral motor neuropathy (especially weakness in the wrist)
• Anemia
• High blood pressure
• Liver, kidney and lung diseases
• Gastrointestinal problems
• Male infertility
• Encephalopathy (altered mental state)
• Damage to the central nervous system (CNS)
• Neurodevelopmental problems, particularly in the early stages of fetal development

Did you know that...?

Metalworkers and especially welders are prone to developing pneumonia infections. These can usually be treated with antibiotics, but there is a clear correlation between welders and an increased risk of developing severe or fatal pneumonia infections.

Medical information

Lead and inorganic lead compounds have been classified as potentially carcinogenic to humans (Group 2A) by the International Agency for Research on Cancer (IARC).

Inhalation is the main method of exposure in the workplace. Larger particles can be introduced into the upper respiratory tract, where they are transported by filament to the esophagus and ingested.

Unlike many other dangerous particles, lead can quickly enter the bloodstream, the respiratory system (lung), and the stomach. Once in the blood, it will be transported through the body until it finally settles mainly in the bones, where it will accumulate progressively. Lead and lead compounds are slowly metabolized over time and eliminated in the urine, with long latencies between exposure and elimination.

When do workplace exposures occur?

Inhalation

Often the main mode of exposure to lead is by inhalation of dust and fumes from the production and handling of alloys and elemental lead. In metal manufacturing, the welding, sanding, cutting, drilling and polishing of lead-containing alloys can give rise to important exposures.

What are welding fumes?

Most welding smoke is composed of filler wire material evaporated by the welding arc. The gaseous metal reacts with oxygen in the air to form a metal oxide and will solidify to form small smoke metal oxide particles. Some welding fumes originate from metals that have been welded.

Most filler wire contains metals that are known to be toxic and can seriously affect health if inhaled. The content of the filler wire and the amount of welding fumes generated will vary according to the welding process.

High temperature work

Other 'high-temperature' or high-energy processes including metal cutting, sanding and even polishing can create metal particles and metal oxides that can be rapidly inhaled.

Other industrial applications may create lead dust, mist or fumes; for example, handling or applying feed or liquid chemicals containing lead.

Peel

The secondary mode of exposure is through skin and eye contact, particularly if lead is in a liquid state, which can easily pass through the skin or cause skin lesions.

Ingestion

Workers may suffer exposure from accidental ingestion of lead, for example workers who eat, drink, smoke or bite their nails with contaminated hands.

Activities/applications in which occupational exposures may occur.

Examples of applications in manufacturing and metallurgical production and also in other industries and processes where people may be exposed to lead compounds:

Production of metals, metal fabrication and related aspects

• Manufacture from materials of any heading, except that of the product
• Working with metallic lead and alloys containing lead
• Recovery and recycling of lead from waste

Note: working with lead at high temperatures (temperature > 500 °C) will result in higher levels of lead fumes compared to other processes where lead dust is more likely to be generated.

Other applications

• Removal, pickling and burning of lead paint
• Hot cutting in demolition and dismantling operations
• Manufacture, breakdown and recycling of lead-acid batteries
• Certain building paints and vehicle spray paints
• Manufacture and processing of lead chemicals and compounds
• Manufacture of lead glass
• Manufacture and use of ceramic pigments, dyes and enamels

Note: working with lead at high temperatures (temperature > 500 °C) will result in higher levels of lead fumes compared to other processes where lead dust is more likely to be generated.

Medical surveillance

Those who are, or are likely to be, significantly exposed to lead are required under national rules to undergo medical examinations and to be under regular medical supervision, including regular checks for lead levels in urine or blood.

National regulations generally define the 'suspension level' as the concentration of lead in blood and urine that cannot be exceeded. If the 'suspension level' is exceeded, the worker will have to be removed from work likely to result in prolonged exposure and an investigation will have to be carried out to implement corrective measures. National legislation may also establish an action level, a concentration (of metal) in urine or blood which, if exceeded, may require the implementation of other control and monitoring measures.

What can I do to protect myself?

Use appropriate controls

Companies should carry out a risk assessment in addition to determining exposure levels against exposure limits to know what control measures they may need.

If necessary, controls from the control hierarchy should be implemented and their effectiveness measured. For example, localized extraction systems (LEVs) can be a highly effective engineering control, used in welding, sanding and many other applications.

An important component of the control of lead exposure is to minimise intake by implementing appropriate hygiene practices, for example washing, changing and showering facilities.

Get the necessary equipment.

In addition to implementing other control measures, the use of personal protective equipment (PPE), such as respiratory protective equipment (PPE), is usually required to minimise exposure and risk to workers.

Respiratory protective equipment (PRE): half masks with filter

3M has a wide range of EPRs that can help minimise exposure to dust, haze, metal fumes, ozone and also to other gases and vapours commonly encountered in metal manufacturing and production, from disposable particle masks to reusable full masks and masks, to battery-powered air purification masks combined with a variety of resistant masks, head units and helmets.

Respiratory protective equipment (PRE): half masks with air supply

3M it also has a wide variety of semi-masks with continuous and on-demand valve air supply, suitable for use in some of the most demanding working environments.

Welding screens with breathing protection

3M it also has a wide range of 3MTM SpeedglasTM welding screens to protect the face and eyes from harmful light, sparks and splashes. All of these welding screens can be used with reusable or disposable half-masks 3M. 3M it also offers welding helmets and screens designed to work with monitored or air supply systems 3M, to provide you with several types of protection in a single product.

Eye and facial protective equipment

Whether it is a 3MTM SpeedglasTM welding viewfinder with a self-obscuring filter or a full and light face screen, 3M has a full range of PPE to protect you from the many dangers involved in working with metals and welds.

Other PPE

3M it also offers a wide variety of different safety solutions you need to work safely, comfortably and effectively, such as:

• Face, eye and head protection
• Reusable and disposable earplugs and earmuffs
• Communication solutions
• Disposable and reusable protective clothing
• Gloves suitable for protecting hands and skin
• Protection against falls
• Solutions for confined spaces
• Individual gas and fixed detection systems
• Fixed flame detection solutions

References

Webelements Webelements. Lead: the basics. [En línea] [consultado el 22 de noviembre de 2018]. https://www.webelements.com/lead/.

Smedley, et al: Smedley, J, Dick, F and Sadhra, S. Oxford Handbook of Occupational Health (second edition). It's 2013.

IT 'S - [metal] and you: Health and Safety Executive (HSE). Lead and you. Working safely with lead. [En línea] [consultado el 1 de octubre de 2018]. http://www.hse.gov.uk/pubns/indg305.pdf.

In order to ensure the proper functioning of the system, the manufacturer shall ensure that the manufacturer complies with the following requirements:. Threshold Limit Values for Chemical Substances and Physical Agents and Biological Exposure Indices

(TLVs)) and BEIs)). 2018

OSHA SLTC: Occupational safety and health administration (OSHA). Safety and Health Topics - Lead. [En línea] [consultado el 1 de octubre de 2018]. https://www.osha.gov/SLTC/lead/index.html.

ASTDR: Agency for Toxic Substances and Disease Registry (ASTDR). Toxic Substances Portal - Lead. [En línea] [consultado el 22 de no viembre de 2018]. https://www.atsdr.cdc.gov/substances/toxsubstance.asp?toxid=22.

NIOSH Pocket Guide: The National Institute for Occupational Safety and Health (NIOSH), which was established by the NIOSH. This is the NIOSH Pocket Guide to Chemical Hazards. [En línea] [consultado el 22 de no viembre 2018]. https://www.cdc.gov/niosh/npg/default.html.

IARC is the International Agency for Research on Cancer. Inorganic and organic lead compounds. [En línea] 2006. [consultado el 1 octubre de 2018]. https://monographs.iarc.fr/iarc-monographs-on-the-evaluation-of-carcinogenic-risks-to-humans-34/.

Antonini: health effects of welding. In the absence of any other evidence, the Commission concludes that the conditions for granting the aid are satisfied.

Metal toxicity and respiratory tract. In this case, the applicant shall provide the information referred to in the first subparagraph.

It is also important to consider the following:. Mortality from infectious pneumonia in metal workers: a comparison with deaths from asthma in occupations exposed to respiratory sensitizers. THORAX Online first, published on 23 August 2009

HSE Burden of cancer: Health and Safety Executive (HSE). RR858 - The burden of occupational cancer in Great Britain - Lung cancer. This is 2012. [En línea] [consultado el: 22 de noviembre de 2018]. http://www.hse.gov.uk/research/rrpdf/rr858.pdf

For the purposes of this Regulation, the following definitions shall apply:. 29 CFR 1910.1025 - Occupational Safety and Health Standards - Toxic and Hazardous Substances - Lead. [En línea] [consultado el 1 de octubre de 2018]. https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.1025.

US: Occupational Health and Safety Administration (OSHA). 29 CFR 1926.62 Lead - Safety and Health Regulations for Construction. [En línea] [consultado el 1 de octubre de 2018]. https://www.osha.gov/laws-regs/regulations/standardnumber/1926/1926.62.

UK: Health and Safety Executive (HSE). L132 - Control of Lead at Work Regulations 2002 - Approved Code of Practice and guidance. [En línea] [consultado el 1 de octubre de 2018].

Australia: Safe work Australia. Lead (inorganic). [En línea] [consultado el 1 de octubre de 2018]. https://www.safeworkaustralia.gov.au/system/files/documents/1702/lead_inorganic.pdf.

Hazard Awareness Bulletin - Lead