Health Implications of PAH Release from Coated Cast Iron Drinking Water Distribution Systems in the Netherlands

http://dx.doi.org/10.1289/ehp.1205220



Table 1. Sampling times, sample conditions, and estimated exposure durations.
Day Sample Condition at sample collection Exposure duration (days)
aWe assumed that the highest PAH concentration of the three samples collected during undisturbed operation was representative of PAH levels for the rest of the year (319 days).
1 Undisturbed 1 At tap during undisturbed normal operation  
3 Undisturbed 2 At tap during undisturbed operation on single feed  
8 Low-flush At hydrant during low-velocity flush (0.35 m/sec), 15 sec after opening hydrant 1
8 High-flush At hydrant during high velocity flush (1.00 m/sec), 15 sec after opening hydrant 1
8 After-flush At tap 15 min after hydrant was closed during undisturbed operation (on single feed) 2
10 Undisturbed 3 At tap during undisturbed operation (on single feed) 319a
15 Repair 1 At tap during undisturbed operation (on single feed) 2–4 hr after pipe was closed for the removal and repair of a piece of cast iron main 2
17 Repair 2 At tap 2 days after pipe was closed during undisturbed operation (on single feed) 40