Personal air sampling

The contractor at Site H had established area and personnel sampling consistent with HAZWOPER requirements. A photo ionization detector (PID) and a real-time aerosol monitor (RAM) were used on a daily basis to screen for potentially hazardous levels of contaminants. On a weekly basis, personal air samples were collected and submitted for laboratory analysis. PPE requirements, however, were often not based on this data because the oversight agency had established inflexible minimum PPE requirements. The audit team found many of the PPE requirements on Site H to be excessive in light of site monitoring data and hazard determinations. 

NIOSH (1976) compared the medical records of 326 workers exposed to phosgene with those of 6,288 unexposed workers from the same plant. Personal air sample measurements at this plant (20-min samples) showed phosgene concentrations ranging from undetectable to 0.02 ppm, and there was a 15 sample average of 0.003 ppm. Fixed-position air samples (20-min or 2-h collection) ranged from undectable to 0.13 ppm in 51 of 56 samples, and >0.14 ppm in 5 of 56 samples. There were no differences in pulmonary function or deaths attributable to respiratory disease between the exposed and control populations. 

Personal air sampling (required by OSHA) is designed to measure an individual worker s exposure to fibers while the worker is conducting tasks that may disturb ACM. The sampling device is worn by the worker and positioned so that it samples air in the worker s breathing zone. 

Estimates of inhalation contact exposure can be made by sampling air in the breathing zone of the applicator. Filter pads attached to respirators can be presumed to trap the pesticide which would have otherwise been inhaled and they can be removed and. analyzed. A second method is to use personal air sampling pumps in which air is drawn over a suitable absorbent material which can subsequently be analyzed for pesticide. 

Whyatt, R.M., Barr, D.B., Camann, D.E., Kinney, P.L., Barr, J.R., Andrews, H.F., Hoepner, L.A., Garfinkel, R., Hazi, Y., Reyes, A., Ramirez, J., Cosme, Y. and Perera, F.P. (2003) Contemporary-use pestiddes in personal air samples during pregnancy and blood samples at delivery among urban minority mothers and newborns. Environmental Health Perspectives, 111, 749-56. 

Biomonitoring data are more challenging to interpret than other exposure measures, such as personal air sampling or exposure diaries, in that they provide information on internal doses that are integrated across environmental pathways and routes of exposure and directly reflect the amount of chemicals that are absorbed into the blood and are distributed, stored, metabolized, and excreted. Therefore, not only must the complexities of the biologic system be considered, but also the properties of the chemicals or their metabolites. 

The individual fluoride exposure and the corresponding body fluid levels were studied in 41 workers in an aluminum plant in Sweden. During the shift (8 h) personal air samplings were performed, plasma fluoride levels and urine fluoride excretion determined. The average total fluoride exposure was... 

Potential exposure to PAHs in road sealing work involving coal tar and bitumen was discussed by Darby et al. (1986). In a study to evaluate inhalation and dermal exposures of 10 roofers removing an old coal tar pitch roof and applying a new asphalt roof, the PAH content of forehead skin wipes taken at the end of the workshift (0.097 pg/cm equivalent to an estimated daily skin exposure of 19.4 pg/day) was found to correlate with the PAH concentrations in personal air samples (10.2 pg/m ) (Wolff et al. 1989c). Relative concentrations of PAHs in air and wipe samples were fluoranthene > pyrene > benz[a]anthracene > benzo[a]pyrene > benzo[b]fluoranthene > benzo[g,h,i]perylene > benzo[k]fluoranthene. Anthracene was found in the air samples but was not detected in the wipe samples. 

Estimation of organophosphorus (OP) pesticide exposure to children in an agricultural community Examination of the quantitative relation between exposure to isocyanates and occupational asthma Explanation of new framework to obtain exposure estimates through the Bayesian approach Combined direct (personal air samples) and indirect (activity pattern model) approaches used in human air pollution exposure assessment Reconstruction of contaminant doses to the public from operations at the Rocky Flats nuclear weapons facility Estimation of historical exposures to machining fluids in the automotive industry... 

In a rayon production factory, exposure to carbon disulfide was measured by personal air sampling and the excretion of TTCA in urine (Meuling et al. 1990). Based on the personal air-sampling, the TWA exposure level for carbon disulfide was 12.6 mg/m3 (4 ppm). The study authors established a calculated biological limit value of 0.77 mg TTCA/g creatinine (0.57 mmol/mol creatinine) to correspond with 95% confidence, to a TWA air concentration lower than the threshold limit value (TLV) of 30 mg/m3. 

An interesting smdy was performed in Scotland to investigate the differences between measurements of personal exposure to PMio and static area measurements in a group of 16 traffic wardens (Watt et al. 1995). Personal air sampling was carried out from 8 am to 4 pm for four consecutive working days over a period of 2 consecutive weeks in November 1994. The results showed that in the first week of samphng, mean PMjo concentration was 123 pg/m, whereas in the second week it decreased to 41 pg/m. ... 

The choice of method depends on the question to be answered. Whereas measurements covering a whole work shift in order to determine the 8-h shift concentration are preferably done by personal air sampling, short-term measurements are often performed using the stationary technique. 

As well as direct-reading tubes for short-term measurements, tubes are also available for long-term monitoring. Here, the air sample is sucked through the tube by use of a personal-air-sampling pump (PAS-pump). These all look more or less the same and have a similar kind of indication to that of short-term tubes.Their area of application corresponds to that of PAS procedures (see Section 6.9.1.4.1). In contrast to these, the concentration can be read directly at the end of monitoring. Personal exposure is calculated based on the air volume pulled through. 

Personal Air Sampling for Cases and Vapors (Active Sampling)... 

The measurement of concentration using personal air sampling is the best method of determining individual exposure at the workplace. 

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