Skip directly to search Skip directly to A to Z list Skip directly to page options Skip directly to site content

NIOSHTIC-2 Publications Search

Search Results

Physicochemical and toxicological characteristics of welding fume derived particles generated from real time welding processes.

Authors
Chang-C; Demokritou-P; Shafer-M; Christiani-D
Source
Environ Sci Process Impacts 2013 Jan; 15(1):214-224
NIOSHTIC No.
20044656
Abstract
Welding fume particles have been well studied in the past; however, most studies have examined welding fumes generated from machine models rather than actual exposures. Furthermore, the link between physicochemical and toxicological properties of welding fume particles has not been well understood. This study aims to investigate the physicochemical properties of particles derived during real time welding processes generated during actual welding processes and to assess the particle size specific toxicological properties. A compact cascade impactor (Harvard CCI) was stationed within the welding booth to sample particles by size. Size fractionated particles were extracted and used for both off-line physicochemical analysis and in vitro cellular toxicological characterization. Each size fraction was analyzed for ions, elemental compositions, and mass concentration. Furthermore, real time optical particle monitors [DustTrak(TM), TSI Inc., Shoreview, Minn.] were used in the same welding booth to collect real time PM2.5 particle number concentration data. The sampled particles were extracted from the polyurethane foam (PUF) impaction substrates using a previously developed and validated protocol, and used in a cellular assay to assess oxidative stress. By mass, welding aerosols were found to be in coarse (PM2.5-10), and fine (PM0.1-2.5) size ranges. Most of the water soluble (WS) metals presented higher concentrations in the coarse size range with some exceptions such as sodium, which presented elevated concentration in the PM0.1 size range. In vitro data showed size specific dependency, with the fine and ultrafine size ranges having the highest reactive oxygen species (ROS) activity. Additionally, this study suggests a possible correlation between welders' experience, the welding procedure and equipment used and particles generated from welding fumes. Mass concentrations and total metal and water soluble metal concentrations of welding fume particles may be greatly influenced by these factors. Furthermore, the results also confirmed the hypothesis that smaller particles generate more ROS activity and should be evaluated carefully for risk assessment.
Keywords
Welders; Welding; Fumes; Physical-chemistry; Toxicology; Metal-fumes; Physical-properties; Aerosols; Chemical-properties; Airborne-particles; Exposure-assessment; Particulate-sampling-methods; Chemical-composition; Oxidative-processes; Bioassays; Analytical-instruments; Analytical-processes; In-vitro-study; Metal-compounds; Metallic-ions; Metals; Welding-equipment
Contact
Philip Demokritou, Harvard School of Public Health-Environmental Health, Boston, MA, USA.
CAS No.
7440-23-5
Publication Date
20130101
Document Type
Journal Article
Email Address
pdemokri@hsph.harvard.edu
Funding Type
Grant
Fiscal Year
2013
NTIS Accession No.
NTIS Price
Identifying No.
Grant-Number-T42-OH-008416
Issue of Publication
1
ISSN
2050-7887
Source Name
Environmental Science: Processes & Impacts
State
MA; WI
Performing Organization
Harvard School of Public Health
TOP