## 5 Conclusions  
The original hypothesis was proved by the experimental test results. BC, despite complying with international certification standards such as the EBC, can induce adverse effects to non-target organisms in the form of acute toxicity. The rotifer _L. quadridentata_ showed substantial toxicological response to the four tested BCs, with LC\({}_{50}\) values in the range of 8.3%-25.1% of effective concentration. _Daphnia magna_ and _M. macrocopa_ showed reduced lethal toxicity when compared with the rotifer. Only _Paramecium caudatum_ did not show any negative response to the exposed BCs. If BC is applied soundly, adhering to the recommended limit masses, no serious adverse effects are to be expected. The present study provides a potential toxicity mechanism to benthic invertebrates when BC is applied to soil. As a result of this study, we recommend to not adhere only to the international certification thresholds concerning BC, but also consider country-specific rules of application meticulously, especially with regard to BC quantities. Conceptualization, F.F., R.R.-M., and P.B. ; methodology, validation, and data curation, F.F. and R.R.-M.; writing, F.F. and R.R.-M; formal analysis and investigation, F.F., D.R.V., and G.E.S.-M.; editing and supervision, P.B. and R.R.-M. This research did not receive any funding and was conducted on the financial means of the doctoral program of Universidad Autonoma de Aguascalientes. We do thank [PERSON]--Institute for Applied Material Flow Management (IfaS)--for his institutional support in undertaking the present BC-related investigation. We do thank Universidad Panamericana for placing the Kon-Tiki Flame curtain kiln at the disposal of the present research. The authors declare no conflict of interest. * _[PERSON] et al. (2015)_ [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Biochar Organic Fertilizers from Natural Resources as Substitute for Mineral Fertilizers. _Agron. Sustain. Dev._**2015**, _35_, 667-678. [CrossRef]
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