Table 3.
Summary of the results as qualitative relative comparison of endpoints for particles generated from combustion of traditional Ethiopian fuel and the reference diesel exhaust particles (DEP, NIST 2975)
| Toxic endpoint/characterisation | Energy density and price of fuel | |||
|---|---|---|---|---|
| Cow dung | Eucalyptus wood | Eucalyptus charcoal | DEP | |
| Total PAH content | + + | + + + | + | + |
| Acellular ROS | + | + | + | + + + |
| BEAS-2B | ||||
| Cytotoxicity | + + + | + + + | – | – |
| DNA damage | + + + | + + + | + + + | + + + |
| Secretion of inflammatory cytokines | – | – | – | N/A |
| THP-1 (serum enriched) | ||||
| Cytotoxicity | – | + | – | – |
| DNA damage | (–) | (+ +) | (–) | (+ + +) |
| Secretion of inflammatory cytokines | (+) | (+) | (–) | N/A |
| THP-1 (serum free) | ||||
| Cytotoxicity | – | + + | – | – |
| DNA damage | – | + | – | + + + |
| Secretion of inflammatory cytokines | + + + | – | + | N/A |
The outcomes (characterization and toxicity) were categorized into no/low/medium/high content/response by weighing in several factors including magnitude, significant difference from control and dose response trends
Relative categories: “–” = no content/response, “+” = low content/response, “+ +” = medium content/response, “+ + +” = high content/response, brackets = only one tested concentration, N/A = not analyzed, PAH polycyclic aromatic hydrocarbons