Biological Monitoring: Assessing Exposure to Hazardous Substances (October 2007)

1. Please read this before using presentation • This presentation is based on content presented at the 2007 Mines Safety Roadshow held in October 2007 • It is made available for non-commercial use (eg toolbox meetings) subject to the condition that the PowerPoint file is not altered without permission from Resources Safety • Supporting resources, such as brochures and posters, are available from Resources Safety • For resources, information or clarification, please contact: ResourcesSafety@docep.wa.gov.au or visit www.docep.wa.gov.au/ResourcesSafety

2. Toolbox presentation:Biological monitoring - assessing exposure to hazardous substances October 2007

3. Hazardous substances Known as toxics, poisons, harmful chemicals, deleterious compounds • Substances used directly in work activities Adhesives, paints, cleaning agents • Substances generated by work activities Welding fumes, reaction products • Naturally occurring substances Dusts, silica, heavy metals • Biological agents Micro-organisms, toxins, allergens

4. What do you know about them? Dusts cause lung disease • Irritation • Asthma • Chronic obstructive pulmonary disease • Silicosis, asbestosis, fibrosis • Lung cancers Inorganic and organic solvents • Irritant effects • Sensitisation • Carcinogenic

5. What else is in the dust? Heavy metals • Arsenic (inorganic only for occupational exposure) • Mercury (elemental) • Lead (carbonate more easily absorbed than sulphides) • Vanadium (as vanadium pentoxide V2O5) • Cadmium • Nickel • Manganese • Thallium • Selenium Native mercury. Source: www.dyet.com/mineral

6. Arsenic Inhaling high levels • Acute exposures cause sore throat or irritated lungs • Chronic exposures are linked with increased rates of lung and skin cancers Ingesting very high levels • Death or • Nausea and vomiting, anaemia (WBC & RBC), abnormal heart rhythm, damage to blood vessels, sensation of "pins and needles" in hands and feet Skin contact • Characteristic staining, corns, wart-like lesions, redness, swelling Organic arsenic from seafood • Less harmful

7. Mercury Nervous system is very sensitive to all forms of mercury Permanent damage to the brain, kidneys, and developing foetus Effects on brain functioning may include: • irritability, shyness, tremors, changes in vision or hearing, memory problems Short-term, high-level exposure may cause: • lung damage, nausea, vomiting, diarrhoea, increases in blood pressure or heart rate, skin rashes, eye irritation

8. Lead High, short-term (acute) exposures • Headaches, tiredness, irritability, constipation, nausea, anaemia, hearing loss, reproductive effects, decreased libido, impotence Long-term (chronic) elevated exposures • Kidney, nerve and brain damage, anaemia, hearing loss, reproductive effects, decreased libido, impotence Lead accumulates in the body with long-term storage Developing foetuses and children highly susceptible • Lower standards for women who can reproduce

9. Vanadium (V2O5) Major effects are on lungs, throat and eyes Acute/chronic reversible effects • Occupational asthma, lung irritation, coughing, wheezing, chest pain, runny nose, and sore throat, mucosal staining

10. Assessing the risk — when? Exploration and scoping studies Mining new orebodies • Arsenopyrite, pyrite and mercury contamination Implementing new processes that change mineral properties • Addition of chemicals that cause redox reactions • Use of heat in refining • Concentration Mine closure and site rehabilitation

11. Assessing the risk — what is present? Analyse using GC/MS, ICP Is the hazardous substance present and in what proportion? • Check the ore and each stage of the process • Does it form fumes, vapours, dusts? • Does anyone work in areas where the hazardous substance may be inhaled or get on skin, eyes or into clothes?

12. Assessing the exposure risk — how? Personal exposure monitoring – how much can be inhaled? • In the air, during work activities • Dust settles, so also check surfaces • Size does matter! • Smaller particles stay airborne for longer • Smaller particles bypass the body’s defence system and travel deeper in lungs • Smaller particles dissolve more easily, releasing hazardous substances into the bloodstream

13. Personal exposure monitoring Measure actual exposures of everyone potentially exposed • Different tasks, conditions and operating levels • Individuals work differently • Exposure is dependent on weather conditions • Larger through-put leads to larger exposures • Higher work rates lead to greater exposures • Usual methods • Inhalable and respirable dust samples • Gravimetric (weighing) • Speciation (specific analysis to identify individual elements)

14. Exposure standards What is an exposure standard? What does it mean to you? Is it a safe level? Is it when harm occurs?

15. Exposure standards cont.

16. Personal exposure monitoring Occupational exposure standards (TWA, 8hr) The occupational exposure standard represents an airborne concentration that normally does not cause adverse health impacts in most of the population when they are exposed to it for 8 hours per day, 40 hours per week for a lifetime • Adjust for extended shift length (based on toxicology) • Adjust for exposures to other metals that act synergistically • Consider an individual’s susceptibility • Review pre-placement baseline biological levels

17. Assessing the risk — how? Analyse using GC/MS, ICP – is it present and in what proportion? • In the ore and each stage of the process Personal exposure monitoring – can it be inhaled? • In the air, during work activities Biological monitoring – is it getting into the body? • Is it having any effect on cells, hormones or enzymes?

18. Biological monitoring form Mines Safety and Inspection Regulations 1995 3.28. Biological monitoring (1) The principal employer and each employer at a mine must ensure that biological monitoring is carried out in respect of employees who engage in specified occupational exposure work at the mine, where there is a valid biological monitoring procedure and a reasonable likelihood that accepted values might be exceeded.

19. Biological monitoring Useful: • to assist in the treatment of the affected worker following accidental exposures • for routine screening to assess if a hazardous substance has entered the body and if it is accumulating to levels that may cause damage • to assess dose-dependent health effects

20. Biological monitoring cont. Measures what gets in • Additional absorption through incidental ingestion and skin uptake • Differences in individual uptake (age related) • Differences in individual behaviour (effort related, hygiene) • Use and effectiveness of PPE In body fluid or tissue (blood, urine, breath) • Storage? Transport? Excretion? • Variable half-life in soft tissue compared with central nervous system (CNS) or bone

21. When should you test? Pre-placement health checks to identify whether an individual will be OK to work in high-risk work • High blood pressure, kidney disease — avoid work with heavy metals Measure baseline levels before starting • Test new starters after first month and then for two months later while learning standard operating procedures Increase frequency of testing based on exposure monitoring and last test result

22. New starters to high exposure risk work Useful information about hazards Training — do you really understand? Supervision • Watch and advise • Do not accuse or label Counselling following elevated levels • Communicate by listening, discussing and making sure It is your responsibility to yourself and your workmates!

23. Ensure you understand your test results Mines Safety and Inspection Regulations 1995 Subdivision C — Information on health surveillance 3.31. Medical practitioner to provide results of health assessment The medical practitioner or approved person under whose supervision a health assessment (including any biological monitoring) is carried out must — (a) notify the employee of the results of the assessment and, if necessary, explain those results; and (b) notify the employer of the outcome of the assessment and advise on the need for remedial action (if any).

24. Biological monitoring standards Known as the biological exposure index (BEI) • Published annually by American Conference of Government Industrial Hygienists (ACGIH) BEI represents: • Level of hazardous substance expected in biological material (urine, blood, hair) following exposure to airborne concentration equivalent to time-weighted average exposure standard • Most people will be protected at this level

25. Levels approaching BEI Biological monitoring results within 10% of BEI indicate: • Controls are not working • Review all controls immediately • Changes to process? • Ventilation? • Team and individual work practices? • PPE: • Correct type? • Used properly? • Adequate storage and maintenance? (Cleaning and replacing canisters)

26. Levels above BEI? Remove individual from further exposure and confirm test result • Total 24-hour urine sample (mercury) Seek medical advice • Specific medical tests to identify damage (neurological - mercury) Doctor to approve return to high-risk work • Return level to be decided by doctor based on • health status • previous exposures

27. Assessing the risk — how? Analyse – is it present and in what proportion? Personal exposure monitoring – can it be breathed? Biological monitoring – is it getting into the body? Health surveillance – is it doing any damage to health?

28. MINEHEALTH — health assessment HAZARDS dust silica noise Questionnaire • Symptoms and smoking status Lung function • Airways and lung capacity Chest x-ray Hearing test • Noise-induced hearing loss

29. Additional health assessment Specific medical tests to detect damage commonly caused by heavy metals: • Neurological and neuro-behavioural tests • Kidney and liver function testing • Handwriting test to detect tremor

30. Health protection Ambient monitoring Biological monitoring Health surveillance External exposure Internal exposure Biochemical effects Biological effects Disease Chemicals: In air, soil, water Hazardous substances, metabolites In blood, urine, breath Protein in urine, DNA changes Cell changes Enzymes, Enzyme levels Poisoning! Estimating the risk

31. Occupational disease notification form Mines Safety and Inspection Regulations 1995 3.39. Notice of occupational disease If an employer at a mine receives advice from an employee or a person on behalf of an employee that the employee has an occupational disease, the employer must, as soon as is practicable, notify the Mines occupational physician in a form approved for that purpose by the State mining engineer that the employee has the disease. Penalty: See regulation 17.1.

32. Where can you find out more? COMING SOON Biological monitoring and risk-based health surveillance — guideline • General information and recommendations about: • Biological monitoring • Risk-based health surveillance • Recommended action levels to trigger: • Risk assessment • Additional testing • Medical removal and health assessment

33. Resources Safety Personal exposure monitoring – CONTAM Biological monitoring – MINEHEALTH • State Mining Engineer may request results Health surveillance – MINEHEALTH • Initial and periodic health assessments • Additional health assessments (risk-based) Notification of occupational disease – MINEHEALTH

34. MineHealth posters available online or as hardcopies (contact Resources Safety)