Table 1. Concentrations, Loads, and Detection Frequencies of PBDD/Fs in U.S. Biosolids from the 2001 U.S. EPA NSSS.

				estimated annual load (kg/year) (min–max)
compound	REP rangesa	concentration in biosolids (ng/kg dw) avg (min, max)b	detection frequency (%)c	in biosolidsd	land-appliede
1,2,3,4,7,8/1,2,3,6,7,8-hexabromodibenzo-p-dioxin (HxBDD)	0.01–0.3	76 (16, 195)	60	0.1–1	0.05–0.8
1,2,3,7,8,9-HxBDD	0.017–0.15	60 (7, 116)	40	0.05–1	0.02–0.5
2,3,7,8-tetrabromodibenzofuran (TeBDF)	0.1–0.97	9 (5, 17)	100	0.04–0.1	0.01–0.07
1,2,3,7,8-pentabromodibenzofuran (PeBDF)	0.004–0.69	27 (10, 45)	40	0.1–0.3	0.03–0.2
2,3,4,7,8-PeBDF	0.08–0.4	60 (6, 200)	100	0.1–1	0.02–0.8
1,2,3,4,7,8- hexabromodibenzofuran (HxBDF)	0.008–0.09	330 (40, 1290)	100	0.3–8	0.1–5
1,2,3,4,6,7,8-heptabromodibenzofuran (HpBDF)	0.0014–0.004	9540 (580, 40900)	100	5–260	2–157

^aREPs were compiled and reported in ref (4).

^bAvg, average; min, minimum; max, maximum.

^cEven numbers in increments of 20 result from the use of 5 mega composite samples.

^dValues were calculated based on estimated biosolids production in 2001 (see the Supporting Information).

^eCalculated based on the estimated percentage of biosolids applied on land in the year 2001 (50–60%).³²⁻³⁴