Charcoal

Bioaccumulation: aquatic / sediment

Additional information

No data are available on the bioaccumulation potential of charcoal to aquatic and terrestrial organisms.

However, many studies are available regarding the effects of carbonaceous sorbents on the bioaccumulation potential of organic pollutants. In situ sorbent amendment, such as coal, charcoal, activated carbon (AC) and biochars, has been identified as a new direction for the management of contaminated sediment/soil sites. The addition of AC has been shown to decrease bioaccumulation of hydrophobic organic contaminants such as polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs) and pesticides in sediment and soil organisms. More specifically, laboratory and field experiments have been conducted to investigate the effects of activated carbon amendment on the bioaccumulation potential of organic contaminants in freshwater oligochate worms(Beckingham and Ghosh 2011)(Beckingham, Buys et al. 2013), benthic organismChironomus tentans(Cui, Hunter et al. 2010)polychaeteNereis diversicolorand gastropodHinia reticulata(Cornelissen, Breedveld et al. 2006), oligochaeteLimnodrilus sp.(Jonker, Hoenderboom et al. 2004), earthwormEisenia foetida(Chai, Currie et al. 2012), e.t.c.. Most of these studies shown that the addition of activecarbon significantly reduced the bioaccumulation potential of the tested compounds, while none of these studies revealed any adverse effects due to bioaccumulation of AC in the tested organisms.

 

In addition, as also presented in Toxicokinetics section, there have not been reports of gastroinestinal absorption and carbon black is probably cleared in faeces following oral administration (Nau et al., 1962 & 1967; NCI, 1985).

In a study using carbon black produced from the furnace process (Lefevre and Joel, 1986), weanling of 4 weeks old and aged 18 months old female Swiss mice were administered by oral gavage a single dose of 7 mg 7Be-labelled furnace carbon black nanoparticles (27 nm diameter). Isotope distribution was measured at 4 hours and 1, 2, 5 and 14 days after administration. At 4 hours post-dosing the total radioactivity in the body (excluding intestines) was approximately 0.01% of the dose in weanlings and 0.005% of the dose in adults. Most of the radioactivity was excreted via the faeces during the first day. A very small fraction of the radioactive dose was also found in the urine at 1, 2 and 5 days post-dosing. The level of radioactivity in the intestines (tissues only) was 0.006 or 0.028% of the dose in weanlings and adults, respectively. About 30% and 20% of this radioactivity were associated with Peyer’s patches in weanlings and in aged mice, respectively. This presence was confirmed histologically by the presence of carbon black particles within Peyer’s patch macrophages. Traces of 7Be-labelled material (radioactivity) remaining in intestinal Peyer’s patches for weanling and aged mice, respectively, expressed as the percentage of total dose administered, were 1.8 x 10-3% and 5.5 x 10^-3% on the first day and 3.3 x 10^-5% and 8.4 x 10^-5% on the fifteenth day. According to the authors, the radioactivity from furnace carbon black nanoparticles of hydrocarbon origin in extraintestinal viscera and blood was extremely low and practically all the label was excreted in the faeces.

Overall, from all available studies there is no evidence for bioaccumulation potential of charcoal in aquatic or terrestrial organisms.