Lead acetate paper ascertains the presence of hydrogen sulfide
Hydrogen sulphide form while processing raw oil
Low concentrations can be toxic hence the requirement to check at certain points of the process
Can also be used to determine levels of sulphide in drinking water, well water or groundwater
Sulphide containing solutions turn the paper from white to brown-black
Thiols, thioketones or mercaptans do not provide a response to this paper