|The authors discuss the appropriateness of establishing occupational medical surveillance programs for workers handling nanomaterials. Because there is no information yet available on health outcomes that may be associated with exposure to nanoparticles, the authors suggest general medical screening, baseline examinations, and establishment of exposure registries to document who is currently working with nanomaterials.|
Reviewed by Diane Mundt, Ph.D., ENVIRON International Corporation.
- Nasterlack, M., Zober, A., and Oberlinner, C. (2007) "Considerations on Occupational Medical Surveillance in Employees Handling Nanoparticles " Int Arch Occup Environ Health. DOI: 10.1007/s00420-007-0245-5
As the manufacture and use of nanomaterials continue to grow, and more workers are potentially exposed to nanoparticles, the wisdom of establishing occupational medical surveillance programs specifically for these workers is receiving greater attention. The authors discuss the basis for occupational medical surveillance in other manufacturing settings, which generally requires knowledge of an existing exposure to a known health hazard as well as associated health effects. If tests are available that can accurately diagnose or detect adverse health outcomes in an early, treatable stage of disease, medical surveillance can become a valuable tool. However, implementing a medical surveillance program requires a reasonable scientific basis for the exposure/effect relationship, which at present is lacking for nanomaterials.
Because nanoparticles may have different (i.e. worse) biological effects than their larger-scale counterparts, and because some studies conducted in animals exposed to nanoparticles show potential hazardous outcomes, the timing is right to consider how to prevent workers from being exposed and whether occupational medical surveillance is warranted.
The authors discuss established concepts for developing occupational medical surveillance comparing these to what is currently known about workplace nanomaterial exposures and health effects.
Nanomaterials exist in countless shapes, forms, and conditions within the "nano" range, and characterizing these differences is important to understanding the potential for exposure and possible health outcomes. Although exposures can be measured, there are no broadly accepted exposure parameters, or metrics specific to nanoparticles, which means that it is difficult to know for certain or quantify what a worker may be exposed to – including whether in fact a hazard is present. The authors indicate that the toxic effects can vary widely, depending on the type of nanomaterial studied. Additionally, although there is limited information on possible health effects of exposure – limited because what we know to date is based on animal experiments and cell culture experiments – these studies do indicate the potential for adverse effects.
The current inability to interpret results of any medical tests that might be performed or used to monitor workers exposed to nanomaterials complicates any decision to implement an occupational medical surveillance program. Specific tests such as x-rays or heart monitoring are well-established tools for detecting known disease entities – however no specific disease is yet known that would justify these tests for those working with nanomaterials. Other tests that might be considered, such as blood tests, are non-specific, and would not be useful for monitoring workers at this time.
The authors, who are occupational physicians in a large chemical company (BASF), indicate that for their employees who use nanomaterials, no special or different medical surveillance is performed, beyond what is routinely done for any workers – including use of "best practices" in handling these materials, and obtaining whatever tests are normally conducted for workers in certain environments. Although the authors do not support implementing special occupational medical surveillance for workers using nanomaterials, they do point to the advantages of establishing registries of these workers, with exposure information, to provide a basis for epidemiological studies in the future.