NORA Manufacturing Sector Strategic Goals
927ZJMJ - Feasibility of Industry-wide studies of workers exposed to nano-tubes
Principal Investigator (PI)
Primary Goal Addressed
Secondary Goals Addressed
Attributed to Manufacturing
This projectís purpose is a continuation to assess the feasibility of conducting industry-wide exposure assessment and epidemiologic studies of US workers producing carbon nano-tubes.
This project contributes to the NIOSH Nanotechnology Research Centerís intermediate goal to evaluate the feasibility of an industry-wide epidemiologic study. Funding for the project comes from an earmark to conduct health and safety research on nanomaterials. The project also addresses the National Toxicology Programís (NTP) goal of identifying nano-material workplaces and production quantities. It also addresses goals of the NIOSH Manufacturing Sector and the Cancer-Reproductive-Cardiovascular, Immune and Dermal Disease Cross-Sectors.
Outputs from this feasibility project include a report describing the workplaces producing carbonaceous nanomaterials (workforce size, location, production volume, size and shape of materials produced, and engineering controls employed), manuscripts documenting the feasibility of industry-wide epidemiologic and exposure assessment studies of carbonaceous nano-material producers and a report on the current exposure control strategies being used in the engineered carbonaceous nano-material industry. Intermediate outcomes may include reductions of exposures to potentially harmful nano-materials, such as single-walled and multi-walled carbon nanotubes.
The purpose of the project is to further assess the feasibility of conducting an industry-wide exposure assessment and epidemiologic study of workers producing carbonaceous nanomaterials in the U.S. The project will focus on manufacturing and materials applications industries involving single-walled and multi-walled carbon nano-tubes (CNT), on the basis of frequency of use within the spectrum of engineered carbonaceous nanomaterials, predicted toxicological endpoints and possible asbestiform behavior of these nano-particles.
The objective of phase one of this feasibility project (completed in FY10) was to collect information on workplace size and growth in recent years, as well as volume and type of nanomaterials produced by manufacturers of carbonaceous nanomaterials. This information has been collected and collated and is now being used for the current phase of the project to recruit relevant manufacturers to permit researchers to assess worker exposure to airborne CNTs. This new information gathered will be important in determining the feasibility of future industry-wide exposure assessment and epidemiologic studies, as well as health outcome surveillance, in the carbon nano-tube manufacturing industry.
Specific steps of the project are: 1) to use the phase one report information to contact companies manufacturing CNTs to facilitate site visits in order to refine exposure assessment techniques for CNTs. (initiated in FY10, will be completed in FY11) 2) Once participants are found a site walk through will be conducted for each facility by industrial hygienists to develop a specific sampling plan for the facility which will take into account the processes and number of relevant employees involved. (4 were completed in FY10, at least 5 additional will be completed in FY11) 3) A total of at least 9 field visits will be conducted initially (4 during FY10 and 5 during FY11) to characterize worker exposure through task based sampling as well as full shift and area samples. In FY11, at biomarker studies will be considered based on findings from exposure assessments. In FY12, reports describing results will be prepared.
This projectís sampling plan will be modeled on field work conducted by other exposure assessment and characterization groups within NIOSH and will include a detailed exposure assessment aspect focusing on an in-depth, task-based and full shift sampling plan and improved methods to measure carbon nano-tubes at low levels. This approach will permit the characterization of CNT worker exposure industry-wide. The project officers will use this exposure assessment information combined with the phase one report to determine the potential utility for further exposure assessment, epidemiologic, and surveillance research needs.
Two draft manuscripts describing the relevance of the collected information for future exposure surveys, medical surveillance, and epidemiologic research on carbonaceous engineered nanomaterials and carbon nano-tubes, as well as describing current exposure reduction strategies used by industry, were prepared and submitted for publication. Both manuscripts will be made available to other interested public health agencies and published in the literature. The timeline for the second phase of the entire feasibility project is 2.5 years, from March 2010 to September 2012.
Engineered nanomaterials represent a fast-growing but ill-characterized industry. Health effects from workplace exposures to engineered nanomaterials are uncertain, but toxicological studies suggest that unique properties of engineered nanomaterials, such as particle number, size, surface area, and shape, may be of greater importance than particle mass and bulk properties in determining exposure and toxicity. Nano-sized particles may be more likely to reach the bloodstream and pass through the bloodbrain barrier than larger particles of the same composition and thus may represent a unique health hazard. Long, thin shape may confer asbestiform properties upon otherwise biologically inert nanomaterials such as carbon nano-tubes.
Health effects from exposure to engineered nanomaterials are uncertain, but likely include injury at the site of initial exposure (e.g., reduced pulmonary function, fibrosis, or lung cancer) or at remote sites (e.g., immunological effects) due to translocation of the particles. Currently, no epidemiologic studies have been conducted among those working strictly with engineered nanomaterials or specifically with carbon nano-tubes.
The information used to define the need and design for this project came from toxicological (mouse and rat) studies, field team sampling visits, and information compiled from proprietary industry surveys (i.e., the Lux Nanotech Reports, vol 4 and 5).
This project proposes an extension to a current feasibility study to identify possible candidate industries or workplaces within the Manufacturing Sector for occupational epidemiology and exposure assessment studies of engineered carbon nanotubes (CNT).
Exposure data will be collected from at least nine participating pilot-scale or full-scale manufacturers of single-walled or multiwalled CNT. This project directly addresses a critical need established by the Strategic Plan of the NIOSH Nanotechnology Research Center and the National Toxicology Programís Plan for Nanotechnology Research to identify nanomaterials producers, estimate volume of nano-material produced and number of workers potentially exposed as well as refining nano-specific exposure assessment methods. It may also lead to cross-sectional studies of biomarkers of exposure and early effects among CNT workers, or cohort studies of health outcomes such as pulmonary fibrosis, cancer, or cardiovascular disease.