Maximum workplace concentrations
In general, the primary aim of defining maximum workplace concentrations is to protect workers’ health, based on scientifically sound evidence.
In Germany, MAK (‘Maximale Arbeitsplatzkonzentration’: maximum workplace concentration) values are derived by the DFG Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area, better known as the MAK Commission. This independent body has been mandated by the German Research Foundation (DFG) to determine the current state of research relating to the health risks posed by substances and materials used in the workplace, and to advise public authorities accordingly. The most important practical results of the Commission’s work are scientific recommendations for the establishment of MAK values and BAT values (biological tolerance values for occupational exposure), for the classification of carcinogenic, embryotoxic/fetotoxic substances and germ cell mutagens, and for the evaluation of measurement methods. The recommendations are freely available online (see Further reading).
Irritant gases | |
High water solubility, e.g. ammonia, sulfur dioxide, hydrogen chloride | |
Moderate water solubility, e.g. chlorine, hydrogen sulfide | |
Low water solubility, e.g. ozone, nitrogen dioxide, phosgene | |
Organic chemicals | |
Organic acids, e.g. acetic acid | |
Aldehydes, e.g. formaldehyde, acrolein | |
Isocyanates | |
Amines. e.g. hydrazine, chloramines | |
Tear (CS) gas, mustard gas | |
Organic solvents, including some leather sprays | |
Some agrochemicals (paraquat, cholinesterase inhibitors) | |
Metallic compounds | |
Mercury vapours | |
Metallic oxides, e.g. those of cadmium, vanadium, manganese, osmium | |
Halides, e.g. zinc chloride, titanium tetrachloride, antimony pentachloride, uranium hexafluoride | |
Nickel tetracarbonyl | |
Hydrides of boron, lithium, arsenic, antimony | |
Metal fumes | |
Complex mixtures | |
Smoke from fires | |
Pyrolysis products from plastics | |
Solvent mixtures | |
Spores and toxins from microorganisms | |
Polymer fumes |
Table 1 – Causes of chemical pneumonitis.
At the European level, the European Commission has set up the Scientific Committee on Occupational Exposure Limit Values (SCOEL), with a mandate to advise the Commission on occupational exposure limits for chemicals in the workplace. It does this by preparing scientific recommendations for the Commission, which are used to underpin regulatory proposals on occupational exposure limit values (OELVs) for chemicals in the workplace. During this procedure, draft recommendations from SCOEL undergo a stakeholder consultation to allow interested parties to submit health-based scientific comments and further data.
Healthcare workers | Other occupations | |
---|---|---|
Airborne, viral | ||
Varicella | All | |
Measles | Physicians and nurses | |
Rubella | All | |
Mumps | Paediatricians and dentists | |
Pertussis | All | |
Parvovirus B19 infection | Nurses | |
RSV infection | All | |
Adenovirus infection | Staff in ophthalmology clinics, intensive care units and longterm paediatric care |
|
Influenza | Physicians and nurses | Office workers |
SARS-coronavirus A | Physicians, nurses, healthcare assistants and others; nursing home attendants; housekeeping personnel, laboratory workers |
Transport workers, business travellers, market for exotic animals |
Avian influenza H5N1 | Physicians, nurses, healthcare assistants |
Poultry, farm and market workers |
Mycoplasma infection | All | |
Airborne, bacterial | ||
Tuberculosis | Nurses, physicians, pathologists, laboratory workers, housekeeping staff |
|
Anthrax | Hospital supply | Agricultural workers, wool sorters, mail sorters |
Psittacosis | Turkey processing | |
Blood-borne, viral | ||
HIV infection | Physicians, nurses, dental workers and dentists, laboratory workers, technicians in dialysis unit, respiratory therapists |
Embalmers or mortuary technicians |
Ebola infection | Nurses |
Table 2 – Respiratory infections that may be occupationally acquired. RSV: respiratory syncyntial virus; SARS: severe acute respiratory syndrome. Reproduced from Ho et al ., 2007, with permission from the publisher.
Recommendations adopted by the SCOEL are also available online (see Further reading).
In the USA, threshold limit values (TLVs) and biological exposure indices (BEIs), as defined by the American Conference of Governmental Industrial Hygienists, are determinations made by a voluntary body of independent knowledgeable individuals. They represent the opinion of the scientific community, after reviewing the available data, that exposure at or below the level of the TLV or BEI does not create an unreasonable risk of disease or injury (see www.acgih.org/TLV/ ).
High-molecular-weight agents | |
Acarians (ticks, mites) | |
Algae | |
Animal-derived antigens | |
Arthropods | |
Biological enzymes | |
Crustacea, seafood, fish | |
Flour | |
Moulds/fungi | |
Mushrooms | |
Plants | |
Plant-derived natural products | |
Pollens | |
Vegetable gums | |
Low-molecular-weight agents | |
Aliphatic amines (ethyleamines and others) | |
Anhydrides | |
Aromatic amines | |
Diisocyanates | |
Drugs | |
Fluxes | |
Fungicides | |
Metals | |
Quaternary amines | |
Reactive dyes | |
Wood dust or bark | |
Various chemicals |
Table 3 – Causes of occupational asthma.
Minerals | |
Coal | |
Man-made vitreous fibres | |
Oil mist | |
Portland cement | |
Silica | |
Silicates | |
Metals | |
Osmium | |
Vanadium | |
Steel dust | |
Organic dusts | |
Cotton | |
Grain | |
Wood | |
Chemicals/gases/fumes | |
Ammonia | |
Firefighting exposures | |
Cadmium | |
Isocyanates | |
Sulfur dioxide | |
Welding fumes | |
Environmental tobacco smoke |