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Panzacchi, S.

Publications and source records attributed to Panzacchi, S..

3 recordsLinked to original sources

Multiple Pesticides and their Mixtures Tested for Genotoxicity in the Micronucleus Assays on Intestinal Caco-2 Cells

Widespread exposure to multiple pesticides might potentially represent a genotoxic risk to humans. However the effects of these mixtures are largely unknown. Genotoxicity is a key characteristic of carcinogens, and its assessment represents an important component of the overall safety assessment of pesticides. In the present study, in vitro micronucleus test on intestinal Caco-2 human cells was performed according to OECD TG 487 in order to ascertain the genotoxicity of ten commonly used pesticides (dose range 0-100 mg L-1), tested as individual pesticides or mixtures. Significant dose-related increases in micronuclei were observed for exposures to lambda-cyhalothrin, tebuconazole, glyphosate, deltamethrin, fluopyram and the synergist piperonyl butoxide. Significant increases of micronuclei were also observed at different doses for cypermethrin, acetamiprid and cyprodinil, however these increases were not dose-dependent. Imazalil genotoxicity could not be analyzed due to confounding of high cytotoxicity even at low doses. Results show that the co-formulant piperonyl butoxide was genotoxic to human cell lines at all tested doses. Moreover, glyphosate, acetamiprid and fluopyram showed genotoxic effects at concentrations of 0.01-1.0 mg L-1. Although previously reported to be not genotoxic cyprodinil and deltamethrin were observed to be genotoxic to Caco-2 cells. A combination of 3 prioritzided pesticides (acetamiprid, glyphosate, tebuconazole) showed genotoxic effects even at the lowest dose. A combination of 8 prioritized pesticides showed genotoxicity at the highest dose. No synergistic interactions in micronuclei formation were evident in either the mixture of 3 or 8 prioritized pesticides. This study provides important information on the genotoxicity of different widely used pesticides and confirms the validity of a component-based approach in genotoxicity assessment of pesticide mixtures. This study was performed as part of the EU SPRINT (Sustainable Plant Protection Transition: A Global Health Approach) project.

pharmacology and toxicology↗

Leukemia in Sprague-Dawley Rats Exposed Long-term from Prenatal Life to Glyphosate and Glyphosate-Based Herbicides

BackgroundGlyphosate-based herbicides (GBHs) are the worlds most widely used weed control agents. There has been intense and increasing public health concern about glyphosate and GBHs since the International Agency for Research on Cancer classified glyphosate as a probable human carcinogen in 2015. AimsTo further study the health effects of glyphosate and GBHs, the Ramazzini Institute, in collaboration with an international network of institutes and universities, has launched the Global Glyphosate Study (GGS), the most comprehensive toxicological study ever performed on these compounds. The GGS is an integrated study designed to test a wide range of toxicological outcomes including carcinogenicity, neurotoxicity, multi-generational effects, organ toxicity, endocrine disruption and prenatal developmental toxicity. The present study reports the first definitive results on leukemia incidence and mortality from the carcinogenicity arm of the GGS. MethodGlyphosate and two GBHs, Roundup Bioflow (MON 52276) used in the European Union (EU) and RangerPro (EPA 524-517) used in the U.S., were administered long-term to Sprague-Dawley (SD) rats beginning in prenatal life until 104 weeks of age via drinking water at doses of 0.5, 5, and 50 mg/kg body weight/day. This dose range encompasses both the EU Acceptable Daily Intake (ADI) and the EU No Observed Adverse Effect Level (NOAEL) for glyphosate. Each experimental group was composed of 51 males and 51 females, the total number animals were 1020 (510 males and 510 females). ResultsIn the animals exposed to glyphosate, a significantly increased trend in incidence of lymphoblastic leukemia was observed in males. In the Roundup Bioflow-treated animals, significantly increased trends were observed in incidence of lymphoblastic leukemia (males and females), monocytic leukemia (males), total myeloid leukemia (males), and all leukemias combined (males and females). In the RangerPro-treated animals, significantly increased trends were observed in incidence of lymphoblastic leukemia (males and females), monocytic leukemia (males) and all leukemias combined (males). 43% of leukemias deaths in the glyphosate and GBHs treated groups occurred before the first year of age (52 weeks). ConclusionsGlyphosate and GBHs at exposure levels corresponding to the EU ADI and the EU NOAEL caused significant, dose-related increased trends in incidence of leukemia, a very rare malignancy, in SD rats. Notably, about half of the leukemia deaths seen in the glyphosate and GBH groups occurred at less than one year of age, comparable to less than 35-40 years of age in humans.

pharmacology and toxicology↗

Glyphosate and its formulations Roundup Bioflow and RangerPro alter bacterial and fungal community composition in the rat caecum microbiome

The potential health consequences of glyphosate-induced gut microbiome alterations have become a matter of intense debate. As part of a multifaceted study investigating toxicity, carcinogenicity and multigenerational effects of glyphosate and its commercial herbicide formulations, we assessed changes in bacterial and fungal populations in the caecum microbiota of rats exposed prenatally until adulthood (13 weeks after weaning) to three doses of glyphosate (0.5, 5, 50 mg/kg body weight/day), or to the formulated herbicide products Roundup Bioflow and RangerPro at the same glyphosate-equivalent doses. Caecum bacterial microbiota were evaluated by 16S rRNA sequencing whilst the fungal population was determined by ITS2 amplicon sequencing. Results showed that both fungal and bacterial diversity were affected by the Roundup formulations in a dose-dependent manner, whilst glyphosate alone significantly altered only bacterial diversity. At taxa level, a reduction in Bacteroidota abundance, marked by alterations in the levels of Alloprevotella, Prevotella and Prevotellaceae UCG-003, was concomitant to increased levels of Firmicutes (e.g., Romboutsia, Dubosiella, Eubacterium brachy group or Christensenellaceae) and Actinobacteria (e.g., Enterorhabdus, Adlercreutzia, or Asaccharobacter). Treponema and Mycoplasma also had their levels reduced by the pesticide treatments. Analysis of fungal composition indicated that the abundance of the rat gut commensal Ascomycota Kazachstania was reduced while the abundance of Gibberella, Penicillium, Claviceps, Cornuvesica, Candida, Trichoderma and Sarocladium were increased by exposure to the Roundup formulations, but not to glyphosate. Altogether, our data suggest that glyphosate and its Roundup RangerPro and Bioflow caused profound changes in caecum microbiome composition by affecting the fitness of major commensals, which in turn reduced competition and allowed opportunistic fungi to grow in the gut, in particular in animals exposed to the herbicide formulations. This further indicates that changes in gut microbiome composition might influence the long-term toxicity, carcinogenicity and multigenerational effects of glyphosate-based herbicides.

pharmacology and toxicology↗