Abstract

INOUE, M.H. et al. Criteria for evaluation of the leaching potential of herbicides used in Paraná. Planta daninha [online]. 2003, vol.21, n.2, pp. 313-323. ISSN 0100-8358.  http://dx.doi.org/10.1590/S0100-83582003000200018.

A survey was carried out on the commercialization of herbicides in Paraná, to verify their total input in the environment. Based on the chemical properties of these herbicides, theoretical criteria ranking them according to their leaching potential were evaluated. The highest volume of commercialization was found to occur from October to November, probably related to the increased demand caused by the summer crop cycle. The mechanisms of action whose consumption is most expressive are the aminoacid synthesis inhibitors (36.9% of the total volume), followed by the photosynthesis inhibitors (31.3%), synthetic auxins (11%) and mitosis inhibitors (8.8%). The herbicides glyphosate (4526.28 t), atrazine (3075.91), 2,4-D (1659.33) and sulfosate (631.60 t) account together for around 65% of the total volume commercialized in the state. Ranking herbicides according to their leaching potential showed that acifluorfen-sodium, alachlor, atrazine, chlorimuron-ethyl, fomesafen, hexazinone, imazamox, imazapyr, imazaquin, imazethapyr, metolachlor, metribuzin, metsulfuron-methyl, nicosulfuron, picloram, sulfentrazone and tebuthiuron are potential leachers according to the three theoretical criteria adopted (GUS, CDFA and Cohen).

Keywords : contamination; environmental impact; mobility; retention.