Polybrominated diphenyl ether (PBDE) levels in beef and dairy cow livers in the U.S. and comparison to paired fat samples

Brominated flame retardants such as polybrominated diphenyl ethers (PBDEs) can contaminate food which results in consumer exposure. In 2018-19, 54 beef livers and 14 dairy cow livers were collected for PBDE analysis along with paired fat samples (previously published) to assess comparisons of congener profiles between liver and fat, concentration levels in liver, and consumer exposure. The mean ΣPBDE concentration in all the livers was 54.03 pg g^-1 wet weight (ww) and the median was 35.45 pg g^-1 ww with concentrations ranging from 4.92 to 426.67 pg g^-1 ww. The congeners with the highest contributions based on the mean were BDE47 (48%), BDE99 (21%), and BDE153 (17%). The ΣPBDE concentrations of the livers when compared to the paired fat samples were not significantly correlated and the congener contribution for BDE99 was lower in the liver compared to the paired fat samples while BDE153 was higher. An average U.S. consumer daily intake of PBDEs in beef liver was estimated to be 0.024 ng kg bw^-1day^-1.