Occupational Exposure to Metalworking Occupational Exposure to Metalworking FluidsFluidsPresented at the Occupational Presented at the Occupational Hygiene Association of Ontario Hygiene Association of Ontario

Spring SymposiumSpring Symposium

March 28, 2007 March 28, 2007

By Lorraine Shaw, B.Sc., CIH, ROHBy Lorraine Shaw, B.Sc., CIH, ROH

Occupational and Environmental Occupational and Environmental Health Laboratory, Health Laboratory,

McMaster UniversityMcMaster University

OutlineOutlineOverviewOverview

Types of MWF, Health Effects, Standards, Types of MWF, Health Effects, Standards, Exposure AssessmentExposure Assessment

Objectives of the StudyObjectives of the StudyMethodology Methodology

Selection of Plants, Laboratory Investigation, Selection of Plants, Laboratory Investigation, Field Investigation, QC and StatisticsField Investigation, QC and Statistics

ResultsResults Laboratory and Field ResultsLaboratory and Field Results

ConclusionsConclusions

Overview Overview (I)(I)

Types of MWFs:Types of MWFs:Oil-based:Oil-based:

– Insoluble (neat)Insoluble (neat)– Soluble (30% - 85% oil)Soluble (30% - 85% oil)

Water-based:Water-based:– Semi-synthetic (5%-30% Semi-synthetic (5%-30%

oil)oil)– Synthetic (no oil)Synthetic (no oil)

Health Effects:Health Effects:CancerCancerHypersensitivity Hypersensitivity

Pneumonitis (HP)Pneumonitis (HP) Respiratory EffectsRespiratory EffectsDermatitisDermatitis

Overview Overview (II)(II)Regulations and Exposure Standards:Regulations and Exposure Standards:

Ontario Ministry of Labour:Ontario Ministry of Labour:

Oil, mineral, mist 5 mg/mOil, mineral, mist 5 mg/m3 3 TWAEV, 10 mg/m TWAEV, 10 mg/m3 3 STEV STEV

ACGIH TLV-TWA (Mineral Oil) in 2006 notice of intended ACGIH TLV-TWA (Mineral Oil) in 2006 notice of intended changes :changes :Mineral Oil Used in metal workingMineral Oil Used in metal workingPoorly and mildly refined 0.2 mg/mPoorly and mildly refined 0.2 mg/m33 (Inhalable) (Inhalable) A2A2Highly and severely refined 0.2 mg/mHighly and severely refined 0.2 mg/m33 (Inhalable) (Inhalable) A4A4

Proposed NIOSH REL for all types of MWF (1998):Proposed NIOSH REL for all types of MWF (1998): 0.5 mg/m0.5 mg/m33(Total) (Total)

0.4mg/m0.4mg/m33 (Thoracic) (Thoracic)

Exposure Assessment: Exposure Assessment: – Sampling Devices: Sampling Devices:

ie. Total, Thoracic (BGI), IOM, Direct Reading Instrument ie. Total, Thoracic (BGI), IOM, Direct Reading Instrument (DustTrak)(DustTrak)

– Particle size selective samplingParticle size selective sampling

The Three Size FractionsThe Three Size Fractions

ObjectivesObjectivesAssess and Validate Analytical MethodsAssess and Validate Analytical MethodsAssess Air Sampling MethodsAssess Air Sampling MethodsCollect Current Representative Occupational Collect Current Representative Occupational

Exposure DataExposure DataAssess Exposure ExceedanceAssess Exposure ExceedanceCompare Ontario Exposure with Published DataCompare Ontario Exposure with Published Data

(Mainly Water-Based MWF’s)(Mainly Water-Based MWF’s)

MethodologyMethodology

Selection of 4 Plants in OntarioLaboratory InvestigationField InvestigationQuality Control and Statistical Analysis

Laboratory InvestigationLaboratory InvestigationNIOSH Method (0500) – Total AerosolNIOSH 5524 – Extractable MWFsHSE Method (MDHS 95) – Marker Element

Sample RecoveryDetection LimitsSample Stability During Storage

Field InvestigationField InvestigationCollection of Air Samples

– Personal– Area

Size Selective Samples– Total– Thoracic (MMAD = 10 µm)– Respirable (MMAD = 4 µm)– Inhalable (MMAD = 100 µm)– Direct Reading Instrument (DustTrak)

Air Sampling DevicesAir Sampling Devices

Total Sampler IOM Inhalable Sampler

BGI 2.69 Cyclone Thoracic Sampler

Respicon Size-Selective Particle Sampler

DustTrak Aerosol Monitor Direct Reading Instrument

Occupational ExposureOccupational Exposure

Examples of Machining Fluids Examples of Machining Fluids

Examples of Examples of FinishedFinished Products Products

QC and StatsQC and Stats

QUALITY CONTROLQUALITY CONTROL– Laboratory– Field

STATISTICAL ANALYSISSTATISTICAL ANALYSIS– Excel and Minitab 13

Results: Laboratory InvestigationResults: Laboratory InvestigationSample RecoverySample Recovery

– Our Study 83.5%– NIOSH Study 95 %

Detection LimitDetection Limit – Our Study 35µg– NIOSH Study 28 µg

Storage Study Storage Study (Sample Stability)(Sample Stability)– Room Temp – NOT Stable– Refrigerator – 2 days– Freezer – 7 days

Results:Airborne Concentrations Results:Airborne Concentrations (mg/m(mg/m33))

• % Exceedance is based on log normal distribution

ze = -log(GM/STD) / log(GSD)

Relationship of Total vs ThoracicRelationship of Total vs Thoracic

Conclusions Conclusions (I)(I)HSE method proved problematicBoth NIOSH method 0500 or 5524 can be usedpreferred method is the 5524Detection limits, sample recovery etc. were

similar to NIOSH studySamples should NOT be stored at Room TempSamples should be analyzed within 2 or 7 days

depending on storage temperature

Ratio of Thoracic to Total aerosol is about 0.7Range of exposures in Ontario (0.04 to 3.84

mg/m3) is similar to others (NIOSH & OSHA)Percent exceedance based on data set and

assumption of log normality is 38% with respect to NIOSH REL

Respiratory effects reported at levels below 0.5 mg/m3

Total Protection requires AIR, DERMAL and FLUID management

Conclusions Conclusions (II)(II)

Thank youThank you

This research study was This research study was funded by a grant from funded by a grant from

the WSIBthe WSIB

Thank youThank you

This research study was This research study was funded by a grant from funded by a grant from

the WSIBthe WSIB