Prior to 1988, PBDEs (sum of 16 congeners including DecaBDE) were generally detected at low-ppb concentrations, but showed a trend toward increasing concentrations over the period 1980-1988.
1988年以前，总的多溴二苯醚测定为10-9低富集度，但在1980-1988年曾一度呈上升趋势。