Effects of Emissions from an Aluminium Smelter in a Tree Tropical Species Sensitive to Fluoride Bruno Francisco Sant’Anna-Santos & Aristéa Alves Azevedo & Thiago Gonçalves Alves & Naiara Viana Campos & Marco Antônio Oliva & Vânia Maria Moreira Valente Received: 24 February 2013 /Accepted: 14 November 2013 # Springer Science+Business Media Dordrecht 2013 Abstract Fluoride is among the most phytotoxic atmo- spheric pollutants, commonly linked to the appearance of lesions in susceptible plants around emitting sources. In order to assess the effects of fluoride on leaves of Spondias dulcis Parkinson (Anacardiaceae), plants were examined 78 km (non-polluted area) and 0.78 km (pol- luted area) from an aluminium smelter. The level of fluoride increased with the exposure time of the plants in the polluted area. On the third day of exposure in the polluted area, necroses with typical colouration were observed. Micromorphological damage began at the abaxial epidermis, mainly associated with the stomata. Starch grain accumulation was more pronounced in the midrib. The cell membranes and chloroplasts were greatly affected by the pollutant. We observed accumu- lation of phenolic compounds and electron-dense mate- rial at the boundaries of the ending veinlets. The micro- scopic events described precede the appearance of symptoms and are therefore of prognostic value in predicting injury by fluoride and will be useful as biomarkers. The high sensitivity of S. dulcis to fluoride and the specificity of the symptoms confirm, for the first time, in an experiment of active biomonitoring, the potential of this species as a bioindicator. Keywords Spondias dulcis . Leaf anatomy . Active biomonitoring . Bioindicator Abbreviations E1 Experiment one E2 Experiment two DM Dry matter DE Day of exposure 1 Introduction The air quality monitoring of highly phytotoxic airborne fluoride in the vicinity of emitters is currently limited to sporadic investigations despite the growing importance of these activities in industrial countries and emerging economies (Franzaring et al. 2007). Fluoride is among the most phytotoxic atmospheric pollutants, commonly linked to the appearance of lesions in susceptible plants around emitting sources, especially factories that pro- duce phosphate fertilisers, aluminium, glass, and ce- ramics (Weinstein and Davison 2004). When the concentration of fluoride surpasses the natural level in the atmosphere, susceptible species pres- ent chlorotic and necrotic lesions on their leaves, a response determined by genetic and edaphoclimatic fac- tors (Weinstein and Davison 2004). While low Water Air Soil Pollut (2014) 225:1817 DOI 10.1007/s11270-013-1817-5 B. F. Sant’Anna-Santos (*) : A. A. Azevedo : T. G. Alves : N. V. Campos : M. A. Oliva : V. M. M. Valente Departamento de Biologia Vegetal, Universidade Federal de Viçosa, Av. PH Rolfs, s/n, Centro, Viçosa 36570-000 Minas Gerais, Brazil e-mail: brunoufv@yahoo.com.br B. F. Sant’Anna-Santos Universidade Federal de Minas Gerais, Campus Regional Montes Claros, Av. Universitária, 1000, Caixa Postal 135, Bairro Universitário, Montes Claros 39404-547 Minas Gerais, Brazil