Bibliography Tag: hhra publication

Benbrook, 2022a

Benbrook, Charles; “Tracking pesticide residues and risk levels in individual samples—insights and applications;” Environmental Sciences Europe, 2022, 34(1); DOI: 10.1186/s12302-022-00636-w.


BACKGROUND: A method is now available to quantify the number of pesticide residues and relative pesticide dietary risks in individual servings of food. The Dietary Risk Index (DRI) system combines the results of United States and United Kingdom pesticide residue testing programs with data on food serving sizes and each pesticide’s chronic Reference Dose or Acceptable Daily Intake. Chronic DRI values are a ratio: the amount of residue in a serving of food relative to the maximum amount allowed by regulators.

RESULTS: The DRI system generates individual sample tables reporting the number of residues detected and individual pesticide and aggregate-pesticide DRI values in specific, individual samples of food. It is the first such system to do so worldwide. Output tables produce accurate estimates of real-world dietary risks based on current toxicology data and exposure benchmarks set by regulators. System outputs allow assessment of the distribution of pesticide dietary risks across foods and pesticides and demonstrate that dietary risk levels are highly skewed. A large number of samples pose moderate, low, or very-low risks, and relatively few samples pose high or very-high risks.

CONCLUSIONS: The DRI system provides the food industry, regulators and analysts with a simple, accessible online tool to assess pesticide dietary-risk levels by food, by pesticide, as a function of country of origin, and on food grown on conventional versus organic farms. DRI system output tables show that the number of residues in a sample of food is a consistently poor indicator of dietary risk levels. By identifying the relatively small number of high-risk samples, efforts to mitigate pesticide dietary risks can be targeted where the most worrisome risks are.



Freisthler et al., 2022

Freisthler, Marlaina S., Robbins, C. Rebecca, Benbrook, Charles M., Young, Heather A., Haas, David M., Winchester, Paul D., & Perry, Melissa J.; “Association between increasing agricultural use of 2,4-D and population biomarkers of exposure: findings from the National Health and Nutrition Examination Survey, 2001–2014;” Environmental Health, 2022, 21(1); DOI: 10.1186/s12940-021-00815-x.


BACKGROUND: 2,4-Dichlorophenoxyacetic acid (2,4-D) is one of the most extensively used herbicides in the United States. In 2012, 2,4-D was the most widely used herbicide in non-agricultural settings and the fifth most heavily applied pesticide in the US agricultural sector. The objective of this study was to examine trends in 2,4-D urinary biomarker concentrations to determine whether increases in 2,4-D application in agriculture are associated with increases in biomonitoring levels of urine 2,4-D.

METHODS: Data from the National Health and Nutrition Examination Survey (NHANES) with available urine 2,4-D biomarker measurements from survey cycles between 2001 and 2014 were utilized. Urine 2,4-D values were dichotomized using the highest limit of detection (LOD) across all cycles (0.40 mug/L or 0.4 ppb). Agricultural use of 2,4-D was estimated by compiling publicly available federal and private pesticide application data. Logistic regression models adjusted for confounders were fitted to evaluate the association between agricultural use of 2,4-D and urine 2,4-D level above the dichotomization threshold.

RESULTS: Of the 14,395 participants included in the study, 4681 (32.5%) had urine 2,4-D levels above the dichotomization threshold. The frequency of participants with high 2,4-D levels increased significantly (p < .0001), from a low of 17.1% in 2001-2002 to a high of 39.6% in 2011-2012. The adjusted odds of high urinary 2,4-D concentrations associated with 2,4-D agricultural use (per ten million pounds applied) was 2.268 (95% CI: 1.709, 3.009). Children ages 6-11 years (n = 2288) had 2.1 times higher odds of having high 2,4-D urinary concentrations compared to participants aged 20-59 years. Women of childbearing age (age 20-44 years) (n = 2172) had 1.85 times higher odds than men of the same age.

CONCLUSIONS: Agricultural use of 2,4-D has increased substantially from a low point in 2002 and it is predicted to increase further in the coming decade. Because increasing use is likely to increase population level exposures, the associations seen here between 2,4-D crop application and biomonitoring levels require focused biomonitoring and epidemiological evaluation to determine the extent to which rising use and exposures cause adverse health outcomes among vulnerable populations (particularly children and women of childbearing age) and highly exposed individuals (farmers, other herbicide applicators, and their families).