Biological monitoring as a part of health surveillance program

What is Biological Monitoring

 Measurement of chemical markers in body media that are indicative of external exposure to chemical agents.
 An assessment of overall exposure to chemical through measurement of appropriate determinant in biological spesimen collected
from workers at specified time.

What is the markers

 Can be found in biological media(markers) such as exhaled breath, flatus, urine, blood, blood serum, blood plasma, sebum, ear
wax, semen, the menses, breast milk, sweet, hair, nail, teeth, tears, faces, saliva, fats, skin, sputum, or internal organ.
 The markers can be the chemical its self or its metabolite or a characteristic reversible biochemical change induce by the
chemical.

Practicality of Biological Monitoring
Only practical if:
 Markers can be identified and quantified in sample
Reliable sampling and analytical procedure available.
 The reference range (regulatory or voluntary) is available in the form of TLV, PEL, BEI

How its works

 Biological monitoring result reflect chemical absorption into body from all route of exposure(inhalation/ingestion/ skin)
 Different chemical and their marker also take different half time to appear in different body media after exposure.
 The excretion characteristic determine recommended sampling time for markers.

When to apply Biological Monitoring

 Biological monitoring is regulated (OEL/BEI/TLV/are documented)
 In evaluation of exposure through other than Inhalation
 In evaluation on effectiveness of PPE program
 Detection of unexpected exposure when air monitoring is not performed
 As guide to justified medical removal protection among worker

Malaysian Legislative on Biological Monitoring
Factories And Machineries (lead) regulation 1984;
Part IX; Reg 34

Biological Monitoring(Lead in Blood) for workers
exposed to lead more than 30 days/years

Interval Categories
At least every 6 month Exposed more 30days/year
At least every 3 month Lead blood level ≥ 40ugm/100gm≤60ugm/100gm
At least monthly Lead blood level ≥ 60ugm/100gm & ≤ 80ugm/100gm
During medical removal period
Female at child bearing age

Malaysian Legislative on Biological Monitoring
Occupational Safety and Health (Use and Standard of Exposure of Chemical Hazardous to Health) Regulations 2000; Part X1,
Reg 29

 Employer to conduct medical surveillance if employee is exposed or likely to be exposed to chemical hazardous To health
Listed in Schedule II

Suport by:
 Guidelines on Medical Surveillance(DOSH.2001) (Element of medical surveillance include biological monitoring)


Sources: from NIOSH Laboratory Division