Environmental concentrations of the cocaine metabolite benzoylecgonine induced sublethal toxicity in the development of plants but not in a zebrafish embryo–larval model

• Benzoylecgonine toxicity was tested on zebrafish embryo/larva and fern spores.
• No effects on zebrafish embryos or larvae toxicity endpoints were observed.
• Benzoylecgonine altered mitochondrial activity and DNA levels in fern spores.
• Phytotoxicity was evidenced at environmentally relevant concentrations.
• Anthropogenic dispersed allelochemicals may pose unacceptable environmental risks.

Several studies have found cocaine and its main active metabolite benzoylecgonine (BE) in the aquatic environment and drinking water, derived from its consumption by humans as well as the inability of water treatment processes to eliminate it. A few studies have already investigated the ecotoxicology of BE to aquatic invertebrates, but none has still addressed the effects of BE on aquatic vertebrates or vascular plants. The goal of this publication is to provide information on the toxicity of environmental concentrations of BE during animal and vascular plant development, in order to contribute to a better understanding of the potential risk of this substance for the environment. BE induced alterations in mitochondrial activity and DNA levels of fern spores at environmental concentrations (1 ng L−1), which could disrupt gametophyte germination. However, BE at concentrations ranging from 1 ng L−1 to 1 mg L−1 did not disturb morphogenesis, hatching, heartbeat rate or larval motility in a zebrafish embryo–larval model. Adverse effects on ferns agree with the allelophathic role described for alkaloids and their unspecific interference with plant germination. Therefore, the anthropogenic dispersion of alkaloid allelochemicals may pose a risk for biodiversity and irrigated food production that should be further investigated.