Can control banding be useful for the safe handling of nanomaterials? A systematic review

Abstract

Objectives Control banding (CB) is a risk management strategy that has been used to identify and recommend exposure control measures to potentially hazardous substances for which toxicological information is limited. The application of CB and level of expertise required for implementation and management can differ depending on knowledge of the hazard potential, the likelihood of exposure, and the ability to verify the effectiveness of exposure control measures. A number of different strategies have been proposed for using CB in workplaces where exposure to engineered nanomaterials (ENMs) can occur. However, it is unclear if the use of CB can effectively reduce worker exposure to nanomaterials. A systematic review of studies was conducted to answer the question “can control banding be useful to ensure adequate controls for the safe handling of nanomaterials.” Methods A variety of databases were searched to identify relevant studies pertaining to CB. Database search terms included ‘control’, ‘hazard’, ‘exposure’ and ‘risk’ banding as well as the use of these terms in the context of nanotechnology or nanomaterials. Other potentially relevant studies were identified during the review of articles obtained in the systematic review process. Identification of studies and the extraction of data were independently conducted by the reviewers. Quality of the studies was assessed using the Methodological Index for Non-Randomized Studies (MINORS). The quality of the evidence was evaluated using Grading of Recommendations Assessment, Development and Evaluation (GRADE). Results A total of 235 records were identified in the database search in which 70 records were determined to be eligible for full-text review. Only two studies were identified that met the inclusion criteria. These studies evaluated the application of the CB Nanotool in workplaces where ENMs were being handled. A total of 32 different nanomaterial handling activities were evaluated in these studies by comparing the recommended exposure controls using CB to existing exposure controls previously recommended by an industrial hygienist. It was determined that the selection of exposure controls using CB were consistent with those recommended by an industrial hygienist for 19 out of 32 (59.4%) job activities. A higher level of exposure control was recommended for nine out of 32 (28.1%) job activities using CB while four out of 32 (12.5%) job activities had in place exposure controls that were more stringent than those recommended using CB. After evaluation using GRADE, evidence indicated that the use of CB Nanotool can recommend exposure controls for many ENM job activities that would be consistent with those recommended by an experienced industrial hygienist. Conclusion The use of CB for reducing exposures to ENMs has the potential to be an effective risk management strategy when information is limited on the health risk to the nanomaterial and/or there is an absence of an occupational exposure limit (OEL). However, there remains a lack of evidence to conclude...

Nanoparticles in Daily Life: Applications, Toxicity and Regulations

“…CB strategies include a hierarchy of risk management approaches for controlling exposures to hazardous nanomaterials that typically encompass regulation of the potential hazard, engineering controls (e.g., local exhaust ventilation, high-efficiency particulate air [HEPA] filters), good occupational hygiene practices (e.g., personal protective equipment), and the need to seek specialist advice depending on a particular CB strategy. 83,84 …”

Effect of orally administered zinc oxide nanoparticles on albino rat thymus and spleen

“…Nanoparticles (NPs) are generally defined as particles within the size range of 1–100 nm . In research fields, their unique mechanical and physicochemical properties as a high surface area to volume ratio and abundant reactive sites on the surface make them the most exciting materials when compared with other bulk chemicals . In the meantime, their properties could be the reasons for their interactions with different biological systems , as the materials that are inert in bulk form may become toxic in the nanosize form .…”

Qualitative and quantitative differences between common control banding tools for nanomaterials in workplaces

“…19,20 It assigns the hazard and exposure bands using a points scoring system ranging from 0 to 10 for a single factor, and then combining them to get the risk band, which is equally divided into four bands. 21,22 (4)The Precautionary Matrix (https://www.bag.admin.ch/bag/ en/home/gesund-leben/umwelt-und-gesundheit/chemikalien/ nanotechnologie/sicherer-umgang-mit-nanomaterialien/ vorsorgeraster-nanomaterialien-webanwendung.html) was developed by the Swiss Federal Office of Public Health and the Federal Office for the Environment in 2008, 23 and was revised in 2010. 24,25 Unlike other tools, it combines hazard and exposure potential in a single score which is subdivided into two bands to determine the precautionary need.…”