9–19%

change per year during a decade. Temporal trends, 1972–2011, of 2,3,7,8-TCDF, 2,3,4,7,8-PCDF, 1,2,3,7,8-PCDF and 2,3,4,6,7,8-HCDF, based on concentrations in pg/g fat, are presented in Fig. 3a–d). The relative annual decrease over the 40 year period for 2,3,7,8-TCDF, 2,3,4,7,8-PCDF, 1,2,3,7,8-PCDF and 2,3,4,6,7,8-HCDF are 6.5%, 6.1%, 5.7% and 6.7%, respectively, with p < 0.001 in each case. The annual relative decrease over the last ten years for 2,3,7,8-TCDF and 2,3,4,7,8-PCDF and 2,3,4,6,7,8-HCDF are 11% (p < 0.002) 7.9% (p < 0.001) and 5.3% (p < 0.001) respectively. No temporal concentration OTX015 research buy trend could be discerned for 1,2,3,7,8-PCDF, during the last ten years. The number of years required to detect an annual change of 10% varied between 7–9 years for the PCDF congeners and the power to detect a 10% annual change was 100% for all of the full time series. The smallest possible trend to detect varied between 3.4–7.9% change per year during a decade. Temporal trends, 1972–2011, of the DL-PCB congeners, CB-118, CB-126 and CB-156 based on concentrations in pg/g ATM Kinase Inhibitor datasheet fat are presented in Fig. 4a–c). The relative annual decrease over the 40 year period for CB-118, CB-126 and CB-156 are 7.6%, 7.0% and 5.8%, respectively, with p < 0.001 in each case. The annual relative decrease over the last ten years for CB-118, CB-126 and CB-156 are 9.7% (p < 0.001), 12% (p < 0.015)

and 8.1% (p < 0.003), respectively. The number of years required to detect an annual change of 10% was 7–10 years, and the power to detect a 10% annual change was 100% for the full time series. The smallest possible trend to detect varied between 5.2%-9.0% change per year during a decade. The present study confirms decreasing temporal trends of the ∑TEQ of ∑PCDDs, ∑PCDFs and ∑DL-PCBs assessed herein (Table 2, Fig. 1). Likewise, it confirms significant concentration declines of the individual Thalidomide PCDD,

PCDF and DL-PCB congeners analyzed. This was to be expected as the time series covers 40 years. The data are in accordance with previously obtained data for ∑PCDDs, ∑PCDFs and ∑DL-PCBs in mothers’ milk from Stockholm, 1972–1997 (Norén and Meironyte, 2000). However, it is striking to see a steeper rate of decline over the most recent years, 2002–2011 for the ∑PCDD and ∑DL-PCB TEQs, than for the full period. In contrast, the steepness of the ∑PCDF TEQ decreasing time trend has not changed much over time. Several of the PCDFs are below LOQ during the latter 10 years, allowing no trend analysis, while 2,3,7,8-TCDF and 2,3,4,7,8-PCDF (WHO-TEF2005 = 0.1 and 0.3) both show stronger and significant declines over the recent 10 years.