In vitro effect of the herbicide glyphosate on human blood platelet aggregation and coagulation

Abstract

Glyphosate [N-(phosphonomethyl)-glycine] is a broad-spectrum, non-selective, postemergence herbicide that is extensively used in agriculture. Published data referring to the effects of this product on human health are contradictory. We showed previously that long-term treatment of rats with low doses of Glyphosate-Biocarb® may induce hepatic histological changes and bleeding without decreasing platelet counts. The aim of the current study was to investigate, in vitro, the effect of glyphosate on human blood platelet aggregation and coagulation. Materials and methods: Platelet aggregation was determined in the platelet-rich plasma using the agents: 6 µM-adenosine diphosphate, 6 µM-epinephrine and 4µg/mL-collagen. Pretreatment with 500 µg/mL glyphosate showed significant hypofunction of the three aggregating agents. The inhibitory effect was dose-dependent at concentrations from 50 to 500 µg/mL. The release of ATP was lower for glyphosate-treated platelets after stimulation by collagen. On the other hand, glyphosate did not promote any inhibitory effects on prothrombin time, thromboplastin time and thrombin time. In conclusion, the results demonstrate that glyphosate promotes changes in the platelet metabolism with an inhibitory effect on primary hemostasis. Rev. Bras. Hematol. Hemoter. 2010;32(4):291-294. Aceito após modificações: 08/06/2010 efeito inibitório na hemostasia primária. Rev. Bras. Hematol. Hemoter. 2010;32(4):291-294.Palavras-chave: Glifosato; agregação plaquetária; secreção plaquetária; coagulação sanguínea; resistência ao herbicida.

Evaluation of biochemical, hematological and oxidative parameters in mice exposed to the herbicide glyphosate-Roundup®

“…However, recent studies have suggested that long-term exposure to the chemical can cause toxicity in pregnant rats, with bone development deficiency in the fetus (Dallegrave, 2003), changes in cellular metabolism (Marc et al , 2004a; 2004b), cutaneous lesions (Amerio et al , 2004), and increased rates of non-Hodgkin's lymphoma (De Ross et al , 2003). Furthermore, studies using low doses of glyphosate-Biocarb ® have shown that the product can cause significant hepatic changes, as well as nasal bleeding without interfering in platelet aggregation (Benedetti et al , 2004; Neiva et al , 2010). …”

A glyphosate-based herbicide disrupted hematopoiesis and induced organ toxicities, ameliorated by vitamin B12 in a mouse model

“…Further investigations revealed suppression of platelet levels in the GBH-exposed mice, perhaps due to platelet breakdown and the diminished bone marrow function owing to GBH toxicity. Related studies on human subjects show that GBH treatment inhibited platelets aggregation ( Neiva et al, 2010 ); posing a significant risk factor for patients on blood thinning medications.…”

Effects of pesticides on rural workers: haematological parameters and symptomalogical reports

“…In addition, the procoagulant proteins are involved in haemostasis consolidation. Studies have shown an inhibition of platelet aggregation, with a decrease in ATP secretion by platelets caused by the mechanism involved in the anti-platelet aggregation effect of glyphosate 46 . Studies with rural workers using sprays of pesticides organophophorus report-ed that there was a significant decrease in mean haemoglobin, haematocrit and platelet count at the end of the day after use of sprays by rural workers 47 .…”