Methods to assess dermal exposures in occupational settings: a scoping review

Abstract

Objectives: The dermal exposure route is expected to become increasingly significant relative to total worker exposure as inhalational exposure limits continue to decrease. However, standardization of occupational exposure assessment methods and scientific consensus are needed. This is the first scoping review mapping the literature across all dermal exposure assessment methods and their targeted substances/chemicals in occupational settings.

Methods: Eligibility criteria broadly included studies reporting any noninvasive dermal exposure assessment method in an occupational setting. The literature search (Web of Science and MEDLINE) was restricted to peer-reviewed, primary literature published in the last 20 years (2002-2022). Titles/abstracts were dual independently screened. Data charting was performed by a single reviewer using standard template. All stages were pilot tested. The JBI (formerly, the Joanna Briggs Institute) scoping review methods and PRISMA-ScR checklist (Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews) were used.

Results: In total, 493 articles were data charted and categorized by 4 study types: methods development (22%), exposure assessment (51%), health outcomes (21%), and controls assessment (6%). Fourteen types of dermal exposure assessment methods were charted with biomarkers (51%), dosimeters (21%), and qualitative assessments such as questionnaires or surveys (17%) most common. Seventeen different chemicals/substances were charted; pesticides (28%) and polycyclic aromatic hydrocarbons (PAHs) (22%) associated with crude oil products and combustion were most common. Mapping between substances and exposure assessment method categories, pesticide dosimeters (11%), and PAH biomarker studies (14%) were most reported. Literature gaps were identified for cleaning agents, hair dyes, glycol ether, N,N-dimethylformamide/N-methyl-2-pyrrolidone, dioxins, and bisphenol A.

Conclusions: To foster scientific consensus, standardization across study reporting is needed for describing: (i) exposure assessment methods used, (ii) worker tasking/conditions, (iii) targeted substances and substance state, and (iv) targeted exposure routes. Overall, this review categorizes, maps, and defines the scope of literature for occupational dermal exposure assessment methods.

Keywords: exposure; industrial health; methodological study; occupational health; occupational safety; risk assessment; skin; standardization; workers; workplace.

Fig. 1.

PRISMA flow diagram. Study flow illustrating article screening, inclusion, and exclusion.

Fig. 2.

Heat map across chemical/substance categories (y-axis) and dermal exposure assessment methods (x-axis). The colors reflect publication counts where hotter colors reflect higher counts. The absence of number tiles reflects gaps in literature for a given substance/method combination. The definitions for dermal exposure assessment methods are presented in Table 2 while definitions for the chemical/substance categories are presented in Table 3. Abbreviations: PAH = polycyclic aromatic hydrocarbon; HC = hydrocarbon; HFR = halogenated flame retardant; DMF/DMP = N,N-dimethylformamide and N-methyl-2-pyrrolidone; PCB = polychlorinated bisphenol; BTEX = benzene, toluene, ethylbenzene, and xylene; BPA/BPS = bisphenol A, bisphenol S, and/or 4-hydroxyphenyl 4-isoprooxyphenylsulfone; WBM = whole body method.