Cardiovascular Effects and Fatality May Differ According to the Formulation of Glyphosate Salt Herbicide

Glyphosate: Hepatotoxicity, Nephrotoxicity, Hemotoxicity, Carcinogenicity, and Clinical Cases of Endocrine, Reproductive, Cardiovascular, and Pulmonary System Intoxication

Glyphosate (GLP) is an active agent of GLP-based herbicides (GBHs), i.e., broad-spectrum and postemergent weedkillers, commercialized by Monsanto as, e.g., Roundup and RangerPro formulants. The GBH crop spraying, dedicated to genetically engineered GLP-resistant crops, has revolutionized modern agriculture by increasing the production yield. However, abusively administered GBHs' ingredients, e.g., GLP, polyoxyethyleneamine, and heavy metals, have polluted environmental and industrial areas far beyond farmlands, causing global contamination and life-threatening risk, which has led to the recent local bans of GBH use. Moreover, preclinical and clinical reports have demonstrated harmful impacts of GLP and other GBH ingredients on the gut microbiome, gastrointestinal tract, liver, kidney, and endocrine, as well as reproductive, and cardiopulmonary systems, whereas carcinogenicity of these herbicides remains controversial. Occupational exposure to GBH dysregulates the hypothalamic-pituitary-adrenal axis, responsible for steroidogenesis and endocrinal secretion, thus affecting hormonal homeostasis, functions of reproductive organs, and fertility. On the other hand, acute intoxication with GBH, characterized by dehydration, oliguria, paralytic ileus, as well as hypovolemic and cardiogenic shock, pulmonary edema, hyperkalemia, and metabolic acidosis, may occur fatally. As no antidote has been developed for GBH poisoning so far, the detoxification is mainly symptomatic and supportive and requires intensive care based on gastric lavage, extracorporeal blood filtering, and intravenous lipid emulsion infusion. The current review comprehensively discusses the molecular and physiological basics of the GLP- and/or GBH-induced diseases of the endocrine and reproductive systems, and cardiopulmonary-, nephro-, and hepatotoxicities, presented in recent preclinical studies and case reports on the accidental or intentional ingestions with the most popular GBHs. Finally, they briefly describe modern and future healthcare methods and tools for GLP detection, determination, and detoxification. Future electronically powered, decision-making, and user-friendly devices targeting major GLP/GBH's modes of actions, i.e., dysbiosis and the inhibition of AChE, shall enable self-handled or point-of-care professional-assisted evaluation of the harm followed with rapid capturing GBH xenobiotics in the body and precise determining the GBH pathology-associated biomarkers levels.

The Cardiotoxic Effect of Roundup® is not Induced by Glyphosate: A Non-specific Blockade of Human CaV1.2 Channels

In Roundup®, the active principle glyphosate is formulated with adjuvants that help it to penetrate the plants' cell membranes. Several reports and reviews report cardiovascular effects of Roundup®, pointing the presence of arrhythmias as a potential consequence of Roundup® toxicity and death cause. However, it still remains debatable whether these cardiac events are related to glyphosate per se or to the Roundup® adjuvants. The present study aims to compare the pro-arrhythmogenic properties of Roundup® and glyphosate in an animal model and in human cardiomyocytes. In isolated guinea pig heart, the cardiotoxicity of Roundup® (significant effect on heart rate and depressive effect on ventricular contractility) was demonstrated with the highest concentrations (100 µM). In human cardiomyocytes, the cardiotoxicity is confirmed by a marked effect on contractility and a strong effect on cell viability. Finally, this Roundup® depressive effect on heart contractility is due to a concentration-dependent blocking effect on cardiac calcium channel CaV1.2 with an IC50 value of 3.76 µM. Surprisingly, no significant effect on each parameter has been shown with glyphosate. Glyphosate was devoid of major effect on cardiac calcium channel with a maximal effect at 100 µM (- 27.2 ± 1.7%, p < 0.01). In conclusion, Roundup® could induce severe cardiac toxicity by a blockade of CaV1.2 channel, leading to a worsening of heart contractility and genesis of arrhythmias. This toxicity could not be attributed to glyphosate.

Cardiovascular damage associated with subchronic exposure to the glyphosate herbicide in Wistar rats

Glyphosate is the most widely used herbicide in the world. Although some studies have shown cardiac electrophysiological changes associated to glyphosate, the histopathological changes that this herbicide may cause in the cardiovascular system are not yet established. The aim of this study was to evaluate the cardiovascular effects of subchronic oral and inhalation exposure to the glyphosate herbicide in rats. Eighty albino Wistar rats were distributed into eight groups (five males and five females/group): inhalation control: nebulization with sodium chloride solution (NaCl); oral control: nebulized feed with NaCl; low inhalation concentration: nebulization with 3.71 × 10-3 grams of active ingredient per hectare (g.a.i./ha) of glyphosate; low oral concentration: nebulized feed with 3.71 × 10-3 g.a.i./ha of glyphosate; medium inhalation concentration: nebulization with 6.19 × 10-3 g.a.i./ha of glyphosate; medium oral concentration: nebulized feed with 6.19 × 10-3 g.a.i./ha of glyphosate; high inhalation concentration: nebulization with 9.28 × 10-3 g.a.i./ha of glyphosate; and high oral concentration: nebulized feed with 9.28 × 10-3 g.a.i./ha of glyphosate. After 75 days of exposure, the animals were euthanized, and aortas and hearts were collected for histopathological analysis. Fatty streaks were observed in most animals exposed to glyphosate and were more prevalent in male rats, regardless of the route of exposure (p < 0.05). There were no differences in the measurements of the thickness of the right and left ventricle or in the collagen density of both ventricles in any of the groups evaluated (p > 0.05). Our study suggests that glyphosate has atherogenic potential, regardless of the concentration and route of exposure.

Derangement of PaCO2 requires physician attention in acute carbon monoxide poisoning

The objective was to describe the prevalence of derangement of the partial pressure of arterial carbon dioxide (PaCO2) and to determine the association between PaCO2 and adverse cardiovascular events (ACVEs) in carbon monoxide (CO)-poisoned patients. Additionally, we evaluated whether the derangement of PaCO2 was simply secondary to metabolic changes. This retrospective study included 194 self-breathing patients after CO poisoning with an indication for hyperbaric oxygen therapy and available arterial blood gas analysis at presentation and 6 h later. The incidence rate of hypocapnia at presentation after acute CO poisoning was 67.5%, and the mean PaCO2 during the first 6 h was 33 (31–36.7) mmHg. The most common acid–base imbalance in 131 patients with hypocapnia was primary respiratory alkalosis. The incidence rate of ACVEs during hospitalization was 50.5%. A significant linear trend in the incidence of ACVEs was observed across the total range of PaCO2 variables. In multivariate regression analysis, mean PaCO2 was independently associated with ACVEs (odds ratio 0.051; 95% confidence interval 0.004–0.632). PaCO2 derangements were common after acute CO poisoning and were not explainable as a mere secondary response to metabolic changes. The mean PaCO2 during the first 6 h was associated with ACVEs. Given the high incidence of ACVEs and PaCO2 derangement and the observed association between the mean PaCO2 and ACVEs, this study suggests that (1) PaCO2 should be monitored in the acute stage to predict and/or prevent ACVEs and (2) further investigation is needed to validate this result and explore the early manipulation of PaCO2 as a treatment strategy.

Use of qSOFA Score in Predicting the Outcomes of Patients With Glyphosate Surfactant Herbicide Poisoning Immediately Upon Arrival at the Emergency Department

AIM

This study aimed to identify whether quick sequential organ failure assessment (qSOFA) performed immediately upon arrival can predict the outcome of patients with glyphosate surfactant herbicide (GlySH) poisoning.

METHODS

Adult patients with GlySH poisoning between January 2006 and April 2017 were included in this retrospective observational study. The qSOFA score (respiratory rate ≥22 breaths per minute, systolic blood pressure <100 mm Hg, and altered mental status) was assessed immediately upon arrival at the emergency department. The primary outcome was in-hospital mortality, and the secondary outcomes were life-threatening complications and organ injury.

RESULTS

Of the 150 patients who ingested GlySH, 14 (9.3%) died. The qSOFA score was significantly higher in the non-survival group (P < 0.001). qSOFA (odds ratio [OR], 2.73; 95% confidence interval [CI], 1.41-5.76) was independently associated with in-hospital mortality. The area under curve value of qSOFA was 0.841 (95% CI, 0.772-0.895). As qSOFA score increased from 0 to 3, the in-hospital mortality significantly increased (P < 0.001). The frequency of life-threatening complications, including organ injury, increased as the qSOFA score increased from 0 to 3 (P < 0.001).

CONCLUSIONS

The qSOFA score measured upon arrival shows good prognostic performance in patients with GlySH poisoning. Moreover, the qSOFA may predict the development of life-threatening complications including organ injury. Thus, more attention should be paid to patients with GlySH poisoning with higher qSOFA scores.

Antioxidant and cytoprotective effects of N-acetylcysteine against subchronic oral glyphosate-based herbicide-induced oxidative stress in rats

It is claimed that oxidative stress has a prominent role in the mechanism of toxic effects formed by glyphosate-based herbicide (GBH) in living systems. A strong thiol compound, N-acetylcysteine (NAC), has antioxidative and cytoprotective properties. The objective in this subchronic toxicity study was to identify the prophylactic effect of NAC over histopathological changes and oxidative stress induced by GBH in blood, renal, liver, cardiac, and brain tissues. A sum of 28 male Wistar rats were divided into four equal groups, each containing 7 rats. During the study, group I (control group) was supplied with normal rodent bait and tap water ad libitum. The applied agents were 160 mg/kg NAC to group II, 375 mg/kg as equivalent to 1/10 of lethal dose 50% (LD50) of GBH to group III, and 160 mg/kg of NAC and 375 mg/kg of GBH together once per day as oral gavage to group IV for 8 weeks. While GBH decreased the levels of GSH in blood, liver, kidney, and brain tissues, it considerably increased malondialdehyde levels. On the contrary, these parameters happened to improve in the group supplied with NAC. Besides, it was seen that NAC was observed to improve the histopathologic changes in rat tissues induced by GBH. It was concluded that NAC protects oxidative stress and tissue damage induced by GBH in blood and tissue and this prophylactic effect could be attributed to its antioxidant and free radical sweeper character.

Successful extracorporeal membrane oxygenation support for severe acute diquat and glyphosate poisoning: A case report

RATIONALE

Because of the lack of an antidote or effective treatment, patients with severe acute diquat and glyphosate poisoning always died within a few hours. Extracorporeal membrane pulmonary oxygenation (ECMO), as an artificial heart-lung supporting system, can be applied to support lung that is expected to recover from reversible pathological damage. However, to our knowledge, the application of ECMO for patients with diquat and glyphosate poisoning has not been reported.

PATIENT CONCERNS

A 40-year-old man ingested in 100 ml of diquat (20 g/100 ml) and 400 ml glyphosate (41 g/100 ml) was admitted to the intensive care unit (ICU), immediately complicated by the development of ventricular fibrillation, respiratory failure, renal failure, and multi-organ failure.

DIAGNOSIS

Diquat and glyphosate poisoning were diagnosed by stated ingestion history, and the diagnostic criteria for acute respiratory distress syndrome (ARDS) and multi-organ dysfunction syndrome were also met.

INTERVENTIONS

He was treated with veno-venous ECMO.

OUTCOMES

He was successfully transferred out of the ICU on day 46 and discharged on day 67. The computed tomography scan showed no obvious pulmonary fibrosis 2 months after poisoning.

LESSONS

ECMO may be effective in the treatment of patients with severe ARDS caused by diquat and glyphosate poisoning when conventional management does not work.