An assessment of the acute dietary exposure to glyphosate using deterministic and probabilistic methods.

Use of glyphosate in crop production can lead to residues of the active substance and related metabolites in food. Glyphosate has never been considered acutely toxic; however, in 2015 the European Food Safety Authority (EFSA) proposed an acute reference dose (ARfD). This differs from the Joint FAO/WHO Meeting on Pesticide Residues (JMPR) who in 2016, in line with their existing position, concluded that an ARfD was not necessary for glyphosate. This paper makes a comprehensive assessment of short-term dietary exposure to glyphosate from potentially treated crops grown in the EU and imported third-country food sources. European Union and global deterministic models were used to make estimates of short-term dietary exposure (generally defined as up to 24 h). Estimates were refined using food-processing information, residues monitoring data, national dietary exposure models, and basic probabilistic approaches to estimating dietary exposure. Calculated exposures levels were compared to the ARfD, considered to be the amount of a substance that can be consumed in a single meal, or 24-h period, without appreciable health risk. Acute dietary intakes were <100% of the ARfD for all foodstuffs, except wild fungi, when calculated using the EFSA model. The model assumptions differ from those of the source model (German national model), resulting in the use of a higher variability factor. Intakes estimated with the German model represented only 18% of the ARfD. The impact of differing assumptions regarding variability and other input parameters is discussed. Probabilistic exposure estimates showed that the acute intake on no person-days exceeded 10% of the ARfD, even for the pessimistic scenario.

An assessment of dietary exposure to glyphosate using refined deterministic and probabilistic methods.

Glyphosate is a herbicide used to control broad-leaved weeds. Some uses of glyphosate in crop production can lead to residues of the active substance and related metabolites in food. This paper uses data on residue levels, processing information and consumption patterns, to assess theoretical lifetime dietary exposure to glyphosate. Initial estimates were made assuming exposure to the highest permitted residue levels in foods. These intakes were then refined using median residue levels from trials, processing information, and monitoring data to achieve a more realistic estimate of exposure. Estimates were made using deterministic and probabilistic methods. Exposures were compared to the acceptable daily intake (ADI)-the amount of a substance that can be consumed daily without an appreciable health risk. Refined deterministic intakes for all consumers were at or below 2.1% of the ADI. Variations were due to cultural differences in consumption patterns and the level of aggregation of the dietary information in calculation models, which allows refinements for processing. Probabilistic exposure estimates ranged from 0.03% to 0.90% of the ADI, depending on whether optimistic or pessimistic assumptions were made in the calculations. Additional refinements would be possible if further data on processing and from residues monitoring programmes were available.

Potato-lactulose breath hydrogen testing as a function of gastric motility in diabetes mellitus.

OBJECTIVE: Scintigraphic determination of gastric emptying is the current standard for the assessment of gastric motility and the diagnosis of diabetic gastroparesis. However, such studies are expensive, inconvenient, and involve exposure to radiation. Because the time course of breath hydrogen (H2) excretion after ingestion of lactulose correlates with upper gastrointestinal transit time, we hypothesized that patients with diabetic gastroparesis would exhibit prolonged breath H2 excretion after ingestion of a test meal containing complex carbohydrate and lactulose compared to subjects without diabetes and subjects with diabetes but without gastroparesis. RESEARCH DESIGN AND METHODS: Ten healthy subjects without diabetes, 10 subjects with diabetes but without gastroparesis (gastric emptying T1/2,T1/2 < 90 minutes), and 10 subjects with diabetes and previously diagnosed gastroparesis (T1/2 > 90 minutes) were admitted for a single 24-hour study. Gastric motility agents were withheld 24 hours prior to the study. Euglycemia was established and maintained overnight in subjects with diabetes with continuous intravenous insulin infusion. At 6:00 AM, all subjects ingested a breakfast containing 100 g of cooked potato starch and 20 g lactulose. Breath H2 excretion was monitored at baseline and every 30 minutes for 12 hours after ingestion of the test meal. RESULTS: Twelve hours after ingestion of the test meal, raw and baseline adjusted breath H2 excretion was significantly elevated in the gastroparesis group compared to the unaffected group with diabetes and the group without diabetes (p < 0.001). The baseline and 12-hour data points were adequate to discriminate between normal and delayed gastric emptying. CONCLUSIONS: We conclude that patients with previously diagnosed gastroparesis exhibit prolonged breath H2 excretion after ingestion of a test meal. This test may prove to be a safe, reliable, and affordable outpatient screening test for diabetic gastroparesis.