| toxicity summary | IDENTIFICATION AND USE: Mefluidide is a solid. It is plant growth regulator and herbicide. It is used to suppress seed heads and fruiting, as well as retarding growth to reduce mowing and trimming. It is also registered for growth control of low maintenance turf on rights-of-ways, airports, public and industrial sites. Mefluidide products can also be used on residential lawns. HUMAN STUDIES: There are no data available. ANIMAL STUDIES: In rats and rabbits, critical effects of acute oral toxicity were tremors, hunched posture, salivation, reduced body weight and body weight gain. Dogs are most sensitive to the effects of mefluidide, which occur at doses as low as 15 mg/kg/day in diets fed for one yr. In addition, dogs fed with mefluidide for one yr exhibited chronic cortical nephrosis at doses of 150 mg/kg/day. Mefluidide was not dermally toxic when tested on rabbits at limit doses of 1000 mg/kg/day for 21 days. Effects were limited to slight erythema at the application site at the 1000 mg/kg/day dose. Increased incidence of liver hyperplastic nodules in both sexes was observed in mice fed with mefluidide at doses of 270 mg/kg/day and higher, however there was no oncogenic response in mice at doses as high as 900 mg/kg/day. Rats fed with mefluidide at doses up to 300 mg/kg/day did not exhibit any carcinogenic response either. Developmental effects of mefluidide in rats included increased number of early resorptions and mean postimplantation loss. These effects were observed at the same dose that caused maternal toxicity indicating there was no increased susceptibility to fetuses. In the 3-generation reproduction toxicity study in rats, the offspring toxicity was characterized by decreased body weights in both sexes and both litters in all generations. It was not teratogenic in rabbits. Eight strains of Salmonella typhimurium and two strains of Escherichia coli were tested for mutagenicity with and without metabolic activation. Mefluidide was not mutagenic in those tests. ECOTOXICITY STUDIES: Mefluidide was practically non-toxic to birds on a acute oral basis. Mefluidide is practically non-toxic to estuarine marine fish and slightly toxic to estuarine marine invertebrates on an acute basis. It was practically non-toxic to honeybees on an acute contact basis. This water-soluble agent is absorbed by grass mainly through its leaves. It inhibits growth due to cell elongation and largely suppresses seed head formation. |
