A new study of flame-retardant chemicals called PBDEs (reported on here) found low relatively levels of the compounds in German breast milk samples—about 2 parts PBDE per billion parts of milk fat.

In contrast, the median level in the Pacific Northwest was about 50 parts per billion, with levels ranging over 300 ppb for a tenth of the samples we analyzed. PBDE concentrations of well over 1,000 parts per billion have been detected in other North American tests. The big difference is that the kinds of PBDEs that are most readily absorbed by living things have mostly been used in the US and Canada. Now, undoubtedly, we’ll be living with that mistake for decades.

One thing of note in the study: vegetarians had lower levels of contamination than people who ate meat, which is a pattern that hasn’t been observed, to my knowledge, in the US or Canada. Typically, fat-soluble contaminants are found at higher concentrations in animal products than in vegetables, grains, and fruits. But it’s unclear whether diet is a significant contributor to the high levels of PBDEs found in North America. Some researchers think that ordinary house dust, containing traces of the compounds that have leached from household consumer goods, is the more likely culprit.