Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

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Additional information

BaS will not occur as such in the environment. In the aqueous and terrestrial environment, barium sulfide dissolves in water releasing barium cations and sulfide anions.

Food chain bioconcentration and biomagnification of sulfide are unlikely(ATSDR 2006). Seven reliable studies were identified on bioconcentration and bioaccumulation of sulfide in marine invertebrates. Reliable data on fish or algae are not available. The highest wet-weight based BCF of 1.6 L/kg wwindicates that sulfides do not have a potential for bioconcentration/bioaccumulation.

Data for barium in aquatic systems indicate that bioconcentration and bioaccumulation are also negligible: the BCF of fish (whole body) ranged from 37.6 to 98.8 (geomean of 4 values: 65.7) (Nakamoto and Hassler, 1992). Whole-body concentrations are significantly higher than reported soft tissue concentrations since Ba (similar to Sr) can replace Ca in bones and hard tissue. Indeed, according to the WHO (1990), approximately 91 % of Ba found in the body are actually in bones. Reported whole-body Ba-levels in fish were similar in different studies; the following ranges were reported; 5.7 - 17.2 μg/g (Nakamoto and Hassler, 1992), 4.37 μg/g (Saiki and Palawski, 1990); 5.1 - 16 μg/g (Schroeder et al, 1988); 4.4 - 12 μg/g (Radtke et al, 1988) and 9-33 μg/g (three fish species; Allen et al, 2001). The data indicate a certain degree of homeostatic control of internal Ba levels by fish. The comparison of internal Ba-levels in bass and carp (with bass being a “higher” trophic level) suggests that barium does not biomagnify in aquatic food chains.

Data on the bioaccumulation of barium and sulfide in soil organisms have not been identified.The evaluation of the bioaccumulative potential of barium and sulfide in the aquatic system, however, seems to suggest that barium and sulfide are also not largely accumulated by terrestrial organisms.