An On-Line Solid Phase Extraction-Liquid Chromatography-Tandem Mass Spectrometry Method for the Determination of Perfluoroalkyl Acids in Drinking and Surface Waters

Table 4

Summary of PFAS concentrations in Italian surface and ground waters.

Samples	Monitoring period	PFBA	PFPeA	PFHxA	PFHpA	PFOA	PFNA	PFDA	PFUnDA	PFDoDA	PFBS	PFHxS	PFOS
Rivers in Northern Italy	2010–2013
(number of samples = 222)	Min (ng/L)	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD
	Median (ng/L)	<LOD	<LOD	4	2	28	<LOD	<LOD	<LOD	<LOD	3	<LOD	3
	Max (ng/L)	411	974	892	946	6.480	174	99	58	19	4.328	36	218
	% positive sample	28	48	75	64	88	46	43	25	16	65	4	55
Rivers in Central Italy	2011–2013
(number of samples = 26)	Min (ng/L)	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD
	Median (ng/L)	16	<LOD	3	2	14	2	<LOD	<LOD	<LOD	<LOD	<LOD	3
	Max (ng/L)	79	15	40	29	222	30	51	11	4	335	<LOD	34
	% positive sample	73	31	58	69	73	69	35	12	8	42	0	62
Transitional waters	2011–2013
(number of samples = 14)	Min (ng/L)	<LOD	<LOD	1	<LOD	1	<LOD	<LOD	<LOD	<LOD	1	<LOD	<LOD
	Median (ng/L)	<LOD	2	2	<LOD	5	<LOD	1	1	2	5	<LOD	4
	Max (ng/L)	31	8	4	1	19	<LOD	1	1	3	10	<LOD	9
	% positive sample	14	64	100	7	100	0	64	79	93	100	0	57
WWTP effluents	2011–2013
(number of samples = 18)	Min (ng/L)	<LOD	<LOD	<LOD	1	3	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD
	Median (ng/L)	<LOD	<LOD	38	22	78	16	14	4	<LOD	<LOD	<LOD	<LOD
	Max (ng/L)	<LOD	582.881	811.431	171.231	712.877	1.080	1.414	1.128	4	4.833.734	<LOD	18.688
	% positive sample	0	44	72	100	100	94	94	78	39	17	0	28
Ground waters	2010–2012
(number of samples = 77)	Min (ng/L)	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD
	Median (ng/L)	<LOD	<LOD	0.3	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD	<LOD
	Max (ng/L)	20	22	37	31	53	13	16	9	13	29	45	121
	% positive sample	67	29	48	40	47	17	16	12	16	38	22	45