Higher proportion of agricultural land use around the residence is associated with higher urinary concentrations of AMPA, a glyphosate metabolite.

INTRODUCTION: Pesticides, including herbicides, are widely used for agricultural and sanitary reasons and concerns have been raised about their various health effects. Little research has been done into the extent to which agricultural land use in the residential surroundings contributes to (internal) exposure of pesticides. OBJECTIVES: We investigated the associations between the proportion of agricultural land use around the residence and the exposure to pesticides in adolescents in Flanders (Belgium). MATERIAL AND METHODS: We included 424 adolescents participating in the fourth Flemish Environment and Health Study (FLEHS IV) between 2016 and 2020. The residential address of all participants was geocoded and the proportion of agricultural land use around the residence was estimated in several buffers (300 m, 500 m, 1000 m and 2000 m). The concentrations of the following biomarkers of pesticides were measured in urine and adjusted for the specific gravity: glyphosate and its metabolite, aminomethyl-phosphonic acid (AMPA); 3-phenoxybenzoic acid (3-PBA); 3,5,6-trichloro-2-pyridinol (TCPy) and 2,4-dichlophenoxy-acetic acid (2,4-D). We categorized the pesticide biomarkers in three categories according to the exposure levels and used ordinal logistic regression models adjusted for sex, season and household education to estimate the odds ratio for an increase in an interquartile range (IQR) of proportion of agricultural land use. We also used binary logistic regression models in which the category of highest exposure was compared to the category of lowest exposure. In addition, we explored potential effect modification by sex and season. RESULTS: We found a significant association between the proportion of agricultural land use in a buffer of 2000 m around the residence and the levels of urinary AMPA divided into three categories (OR = 1.35 for an IQR increase in the proportion of agricultural land use around residence; 95% CI: 1.00-1.83). This association was less pronounced and not statistically significant for the other studied pesticides (OR ranging between 0.95 and 1.16). Stratified analysis showed the strongest association of the proportion of agricultural land use within 2000 m buffers for AMPA among boys (OR = 1.89; 95% CI: 1.19-3.04). Results using smaller buffers were comparable, but did not reach statistical significance. CONCLUSION: Our findings suggest that a higher proportion of agricultural land use around the residence might increase exposure to AMPA.

Application of ICP-MS and HPLC-ICP-MS for diagnosis and therapy of a severe intoxication with hexavalent chromium and inorganic arsenic.

ICP-MS and HPLC-ICP-MS were applied for diagnosis and therapeutic monitoring in a severe intoxication with a liquid containing hexavalent chromium (Cr(VI)) and inorganic arsenic (iAs). In this rare case a liver transplantation of was considered as the only chance of survival. We developed and applied methods for the determination of Cr(VI) in erythrocytes and total chromium (Cr) and arsenic (As) in blood, plasma, urine and liver tissue by ICP-MS. Exposure to iAs was diagnosed by determination of iAs species and their metabolites in urine by anion exchange HPLC-ICP-MS. Three days after ingestion of the liquid the total Cr concentrations were 2180 and 1070µg/L in whole blood and plasma, respectively, and 4540µg/L Cr(VI) in erythrocytes. The arsenic concentration in blood was 206µg/L. The urinary As species concentrations were <0.5, 109, 115, 154 and 126µg/L for arsenobetaine, As(III), As(V), methylarsonate (V) and dimethylarsinate (V), respectively. Total Cr and As concentrations in the explanted liver were 11.7 and 0.9mg/kg, respectively. Further analytical results of this case study are tabulated and provide valuable data for physicians and toxicologists.