Abstracts Book - IMRC 2018

• SWMC-O031
OXYGEN CONTENT DETERMINES THE BIO-REACTIVITY AND
TOXICITY PROFILES OF CARBON BLACK PARTICLES
Sijin Liu 1
1 Research Center for Eco-Environmental Sciences, State Key Laboratory of Environment
Chemistry and Ecotoxicology, China.
In spite of the considerable efforts invested to understand the environmental
health and safety (EHS) impacts of ultrafine particles, such as the representative
PM2.5, there are still significant knowledge gaps to be filled. No conclusive
understandings have been obtained about the physicochemical determinants in
accounting for differential adverse outcomes. Here we compared the
cytotoxicity of four carbon black (CB) particles with similar physicochemical
properties except for their oxygen contents (C824455 < C1864 < Printex U <
SB4A). We found that these four CB particles manifested in vitro and in vivo
cytotoxicity reversely related to their oxygen contents, namely a hierarchy of
cytotoxicity: C824455 > C1864 > Printex U > SB4A. Among these CB particles, the
most significant lung injury (e.g. collapses and inflammation) and macrophagic
activation were found for C824455 and C1864, in particular for C824455. All
these differences in toxicity profiles, including in vitro and in vivo cytotoxicity,
pro-inflammatory effects and direct damages to the lung epithelia, should be (at
least partially) ascribed to the oxygen content in these CB particles that in turn
determined their transformation, i.e. the different aggregation states.
Nonetheless, PM2.5 likewise caused severe in vivo and in vitro toxicities to the
lung cells and macrophages. This study thus offers more insights into the
structure-activity relationship (SAR) and opens a new avenue to elucidate the
physicochemical determinants in evoking lung injuries by ultrafine airborne
particles.
Acknowledgment: This work was supported by grants the National Natural
Science Foundation of China (Grant nos.: 21425731, 21637004 and 91543124),
a grant under the national “973” Program (Grant no.: 2014CB932000), and the
Strategic Priority Research Program of the Chinese Academy of Sciences (Grant
no. XDB14000000).
Keywords: Carbon black, Inflammatory responses, Macrophage
Presenting authors email: sjliu@rcees.ac.cn