Glyphosate in Portuguese Adults - A Pilot Study.

BACKGROUND: Glyphosate is a broad-spectrum biocide and the active ingredient in the most widely used herbicides worldwide. Since 2015, when the International Agency for Research on Cancer classified it as a Class 2A carcinogen, global interest in this chemical spiked particularly as regards exposure of the general population. OBJECTIVE: An exploratory glyphosate exposure assessment was conducted among Portuguese adults. METHODS: Self-selected participants provided first morning urine which was tested for glyphosate and its metabolite aminomethylphosphonic acid (AMPA) at two distinct periods of time, by two different laboratories using gas chromatography with tandem mass spectrometry (GC-MS-MS) and high performance liquid chromatography linked to triple quadrupole mass spectrometry (HPLC-MS/MS), respectively. RESULTS: In the first round of testing 28% and 50% presented detectable levels of glyphosate and AMPA respectively, with median values of 0.25 and 0.16 µg/L. Systematically available internal dose values were 8.20E-06 mg/Kg (glyphosate) and 5.04-05 mg/Kg (AMPA). In the second round 73% and 97% presented detectable levels of glyphosate and AMPA respectively with median values of 0.13 and 0.10 µg/L. Systematically available internal dose values were 4.00E-06 mg/Kg (glyphosate) and 3.00E-06 mg/Kg (AMPA). CONCLUSIONS: Glyphosate exposure was detected among Portuguese adults, with percentages of glyphosate and AMPA contaminated urine in both rounds of testing and above values from previous studies in other European countries. Systematically available internal doses values were below EFSA's risk assessment values (ADI or AOEL), and as such, the concentration values measured in this study are not per se a human health problem. Even though there were study limitations, it is the first assessment in Portugal and contributes to the overall knowledge map of glyphosate exposure in Europe.

Exposure assessment using human biomonitoring for glyphosate and fluroxypyr users in amenity horticulture.

BACKGROUND: Pesticides and their potential adverse health effects are of great concern and there is a dearth of knowledge regarding occupational exposure to pesticides among amenity horticulturalists. OBJECTIVE: This study aims to measure occupational exposures to amenity horticuturalists using pesticides containing the active ingredients, glyphosate and fluroxypyr by urinary biomonitoring. METHODS: A total of 40 work tasks involving glyphosate and fluroxypyr were surveyed over the period of June - October 2015. Workers used a variety of pesticide application methods; manual knapsack sprayers, controlled droplet applicators, pressurised lance applicators and boom sprayers. Pesticide concentrations were measured in urine samples collected pre and post work tasks using liquid chromatography tandem mass spectrometry (LC-MS/MS). Differences in pesticide urinary concentrations pre and post work task, and across applications methods were analysed using paired t-tests and linear regression. RESULTS: Pesticide urinary concentrations were higher than those reported for environmental exposures and comparable to those reported in some agricultural studies. Log-transformed pesticide concentrations were statistically significantly higher in post-work samples compared to those in pre-work samples (paired t-test, p<0.001; for both µgL-1 and µmol/mol creatinine). Urinary pesticide concentrations in post-work samples had a geometric mean (geometric standard deviation) of 0.66 (1.11) µgL-1 for glyphosate and 0.29 (1.69) µgL-1 for fluroxypyr. Linear regression revealed a statistically significant positive association to exist between the time-interval between samples and the log-transformed adjusted (i.e. post- minus pre-task) pesticide urinary concentrations (ß=0.0039; p<0.0001). CONCLUSION: Amenity horticulturists can be exposed to pesticides during tasks involving these products. Further research is required to evaluate routes of exposure among this occupational group.

1H-nuclear magnetic resonance spectroscopy-based metabolic assessment in a rat model of obesity induced by a high-fat diet.

Obesity, whose prevalence is increasing rapidly worldwide, is recognized as a risk factor for diabetes, cardiovascular disease, liver disease, and renal disease. To investigate metabolic changes in the urine of a rat model of obesity induced by a high-fat diet (HFD), rats were divided into the following four groups based on the diet type and degree of weight gain: normal-diet (ND) low gainers, ND high gainers, HFD low gainers, and HFD high gainers. Biochemical analyses of visceral fat-pad weight, plasma, and liver tissues were performed. The (1)H-nuclear magnetic resonance ((1)H-NMR) spectra of urine were analyzed using multivariate statistical analysis to identify the separation of the groups. It was observed that the metabolic profile of urine obtained by (1)H-NMR-spectroscopy-based metabolomic analysis differed between ND low gainers and ND high gainers even though these animals consumed the same normal diet. Several key metabolites in urine, such as betaine, taurine, acetone/acetoacetate, phenylacetylglycine, pyruvate, lactate, and citrate contributed to the classification of these two groups. The metabolic profile of urine also differed between ND low gainers and HFD high gainers, which consumed the different diet and showed a different weight gain. This study has identified features of urine metabolites in various groups and demonstrated the reliability of an NMR-based metabolomics approach to investigate the effects of the diet and the physical constitution on obesity.

Guanidinoacetate and creatine plus creatinine assessment in physiologic fluids: an effective diagnostic tool for the biochemical diagnosis of arginine:glycine amidinotransferase and guanidinoacetate methyltransferase deficiencies.

BACKGROUND: Disorders of creatine metabolism arise from genetic alterations of arginine:glycine amidinotransferase (AGAT), guanidinoacetate methyltransferase (GAMT), and the creatine transporter. We developed a strategy for the detection of AGAT and GAMT defects by measurement of guanidinoacetate (GAA) and creatine plus creatinine (Cr+Crn) in biological fluids. METHODS: Three patients with AGAT deficiency from the same pedigree and their eight relatives, as well as a patient affected by a GAMT defect and his parents were analyzed by a new HPLC procedure in comparison with 90 controls. The method, which uses precolumn derivatization with benzoin, separation with a reversed-phase column, and fluorescence detection, has shown good precision and sensitivity and requires minimal sample handling. RESULTS: In the three AGAT patients, plasma GAA was 0.01-0.04 micro mol/L [mean (SD) for neurologically normal controls was 1.16 (0.59) micromol/L], Cr+Crn was 15-29 micro mol/L [reference limit in our laboratory, 79 (38) micromol/L]. Urinary GAA was 2.4-5.8 micro mol/L [reference, 311 (191) micromol/L], and Cr+Crn was 2.1-3.3 mmol/L [reference, 9.9 (4.1) mmol/L]. We found a smaller decrease in GAA and Cr+Crn in some carriers of an AGAT defect. In the patient with GAMT deficiency, plasma and urine GAA was increased (18.6 and 1783 micromol/L, respectively), and Cr+Crn was decreased in plasma (10.7 micromol/L) and urine (2.1 mmol/L). GAA was increased in the parents' plasmas and in the mother's urine. CONCLUSION: The assessment of GAA is a new tool for the detection of both GAMT and AGAT deficiencies.