NORA Manufacturing Sector Strategic Goals
R013669 - 021H: Influence of Metal-Working Fluid Formulations on Dermal Absorption of Biocides (3669)Start Date: 8/1/2010
End Date: 7/31/2013
Principal Investigator (PI)Name: Joan Karr
Sub-Unit: Office of Extramural Projects
Funded By: NIOSH
Primary Goal AddressedNone
Secondary Goal AddressedNone
Attributed to Manufacturing100%
When the skin of workers is exposed to different industrial formulations, it is often assumed that dermal absorption of harmful substances will vary according to the chemical composition of these different formulations. It is often assumed that this may explain why one formulation may be more harmful locally and/or systemically than another formulation. The problem the researchers hope to address is: How does one accurately predict these formulation effects at the chemical manufacturing end or onsite production end and thus mitigate occupational exposure to formulations that may promote dermal absorption of a potential toxicant? The EPA Guidance Document on Dermal Risk Assessment (EPA, 2004) recommends a regression model for predicting skin permeability of single chemicals but provides no guidance on mixtures or formulations. The products of this proposal will be regression models that will be predictive of dermal absorption of various biocides in three broad classes of industrial metal working fluids (MWFs). The end user (e.g., MWF manufacturer, formulator, MSDS) will have the choice of using either our derived regression models and/or membrane coated fiber (MCF) array to accurately predict skin permeability in defined MWF formulation or compare across formulations without the need for in vitro or in vivo testing. This will ultimately be used to inform the development of formulations that afford greater protection to workers.
"The long-term goal is to understand physicochemical and chemical-biological interactions in a metal-working fluid (MWF) formulation in order to be able to predict quantitatively how these formulations influence dermal absorption of industrial biocides used as additives in these chemically complex formulations. Current dermal risk assessments only evaluate dermal absorption of single chemicals which has limited use in occupational exposure to chemically complex MWF formulations. The primary objective of this research project is to utilize the membrane-coated fibers (MCF) to characterize the distribution behavior between a defined MWF formulation, a MWF biocide, and an inert membrane and to relate this phase distribution to solvation parameters within a linear solvation energy relationship (LSER) framework that is also
Workers in the metal fabrication industry are more often exposed to metal working fluids (MWF) and its components such as biocides via the skin that can cause harm to the skin and/or the entire body if absorbed by the dermal route. Many of these workers are exposed to more than one chemical additive in any given MWF formulation, and there is little or no means of estimating what class of MWF formulations can result in increased or decreased absorption of biocides across skin. This proposal describes a novel technique that models biocide absorption in skin on the basis of quantitative changes in physicochemical properties associated with the formulation interacting with a model membrane and then validated in skin in vitro and in vivo to determine validity of these models in an occupational dermal exposure. Ultimately, the products of this research will help inform the development and risk assessment of formulations that afford greater protection.