Human Exposure to Glyphosate and Methods of Detection: A Review

Abstract

Glyphosate is a broad-spectrum herbicide used extensively worldwide. The carcinogenic potential of glyphosate has been debated. This review aimed to describe human exposure, report environmental air concentrations in relation to occupational exposure, and identify the methods used to analyze glyphosate or AMPA concentrations. We searched, Google Scholar, Science Direct and PubMed for relevant papers in Thai or English, published from 2004 to 2017. Thus, 16 studies were identified. The results show that glyphosate and aminomethylphosphonic acid (AMPA) are markers of both internal and external exposure dose. Glyphosate is generally detected at concentrations comparable to or higher than AMPA. Human exposure has been assessed with measured levels of glyphosate ranging from 0.02 to 233 µg/L and a range of AMPA of 0.15 to 2.63 µg/L in human urine. The highest concentrations of glyphosate and AMPA found in blood were 171.1×103 and 2,600 µg/L, respectively, from acute poisonings and intentional self-harm. Environmental air concentrations of glyphosate ranged from less than 0.01 to 46.80 µg/m3 in the working field areas. Four methods used to analyze glyphosate and AMPA were identified: ELISA, HPLC-fluorescence/MS, GC-MS, LC-MS. While these results indicate the level of human exposure to glyphosate, the resulting human health effects of exposure are still uncertain. Therefore, there is a need for more investigation into human health risk assessment and application of health surveillance programs, particularly among glyphosate applicators.

Biological Monitoring of Glyphosate Exposure among Knapsack Sprayers in Khon Kaen, Thailand

“…An HQ of less than 1 is considered acceptable, while an HQ value of greater than 1 suggests a possible risk to human health [12]. There are various methods for determining glyphosate exposure concentrations [13]. To enhance the sensitivity of the detection of chemicals, preconcentration methods have been developed for the determination of substances at trace levels.…”