Table 2.

Mean Ag NP concentrations in wastewater effluents from various wastewater treatment plant types (WWTPs)

WWTP type	Plant ID	Total suspended Ag (ng/L)	∑ Ag NP (ng/L)	% as NP
Aerated lagoon	TB	6.129	0.468	7.6
	JL	1.284	0.084	6.6
Secondary	SB	0.104	0.005	4.8
	WL	0.585	0.027	4.6
	PD	0.208	0.007	3.4
	HG	2.940	0.052	1.8
	PA	0.635	0.023	3.6
	PW	0.842	0.031	3.7
Advanced with filtration	E	3.284	0.057	1.7
	PN	3.101	0.122	3.9