The ability to rapidly detect {TAIL ~ a trace amount} of {HEAD ~ lead species} on site is very desirable 
The ability to rapidly detect { TAIL ~ a trace amount } of { HEAD ~ lead species } on site is very desirable
OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH