Lecture 5 - Exposure Assessment Flashcards
determining need for quantitative sampling
type of hazard, toxicity, quantity in use, duration of use, past monitoring use, established models, specific OELs
measurement methods are resource intensive, cost prohibitive
Types of measurements
air sampling, water sampling, bulk material sampling (including food), surface sampling (including dermal), dust or soil sampling, biomarkers
Sampling Strategy concerns
issue, tox concerns, chemcial properties, standards, variablility in exposure, sensitivity needs, budget
Sampling Steps
- why do sampling?
- how are they regulated?
- determine sampling time
- consult qualified lab
- choose air sampling method
air sampling methods
area v personal, twa vs direct reading, active vs passive sampling
personal work practices could greatly influence exposure
sampling collection media
filters for pm, sorbent materials for gases, gravimetric vs analytical methods
why do air sampling
ensure compliance, productivity of workforce, choose proper PPE, evaluate effectiveness of engineering controls, educate workers about the importance of safe work practices, to perform epi studies, determine source of leaks, avoid litigation, establish regulated areas following leak or spill
How are your chemicals regulated? i.e., types of air OELs
TWAs, Short Term exposure limits, ceiling values
IDLH, Action level
immediately dangerous to life or health concentrations, Action level (usually 1/2 TLV),
skin notation,
denotes possibility of significant dermal absorption, skin swaps, define and characterize materials,
biological monitoring
purpose - assess body burden of specific chemicals AGIH BEIs
sampling - blood, urine, breath
biological vs environmental
biological monitoring techniques may offer better estimates of internal exposure, biological parameters may be more directly related to adverse health outcomes, biological monitoring takes into consideration accumulation through all routes,
obviously biological monitoring can’t hint at source
