Abstract:
This study was undertaken to assess the levels of eight PBDE congeners, namely: PBDE-17, 47, 100, 99,
154, 153, 183 and 209 in eggshells of Southern Ground-Hornbill (SGH) Bucorvus leadbeateri and Wattled
Crane (WC) Bugeranus carunculatus obtained from different nesting sites within the eastern savanna of
Limpopo Province and the midlands of KwaZulu-Natal, respectively. Analyses were performed using
gas chromatography–mass spectrometry employing the electron impact ionization technique. The results
obtained indicated that the lower brominated congeners were predominant in both species. The total
PBDEs ranged between not detected (ND) to 264 lg g 1 lipid weight and 5.98–7146 lg g 1 lipid weight
in the SGH and WC samples, respectively. More so, the mean recoveries of the 13C-labelled surrogate
standards ranged between 40% (PBDE-100) and 136% (PBDE-99). The potential hazards to these birds
via PBDEs exposure were evaluated by determining the hazard quotients (HQs) by employing the
established Lowest Observed Effect Level (LOEL) values associated with impaired pipping and hatching
success as well as that associated with impaired reproduction. HQs values varying from 0.58 to 0.94
and 27.71 to 45.27, respectively were obtained for SGH and WC species. This implies that the SGH
populations are exposed to low to moderate hazards, while the WC populations are susceptible to high
hazards. Considering the potential threats posed by PBDEs, particularly to the WC species, it is likely that
exposure to the current environmental levels of PBDEs by these birds may contribute to their reduced
breeding success and declining population trends.
